Bump version to 0.4.0

Fixes #287

.github/workflows/cont_integration.yml

@@ -41,6 +41,8 @@ jobs:
         run: rustup set profile minimal
       - name: Add clippy
         run: rustup component add clippy
+      - name: Update toolchain
+        run: rustup update
       - name: Build
         run: cargo build --features ${{ matrix.features }} --no-default-features
       - name: Clippy
@@ -66,6 +68,8 @@ jobs:
         run: rustup default nightly
       - name: Set profile
         run: rustup set profile minimal
+      - name: Update toolchain
+        run: rustup update
       - name: Test
         run: cargo test --features test-md-docs --no-default-features -- doctest::ReadmeDoctests
 
@@ -96,6 +100,8 @@ jobs:
         run: $HOME/.cargo/bin/rustup default stable
       - name: Set profile
         run: $HOME/.cargo/bin/rustup set profile minimal
+      - name: Update toolchain
+        run: $HOME/.cargo/bin/rustup update
       - name: Start core
         run: ./ci/start-core.sh
       - name: Test
@@ -129,6 +135,8 @@ jobs:
         run: rustup set profile minimal
       - name: Add target wasm32
         run: rustup target add wasm32-unknown-unknown
+      - name: Update toolchain
+        run: rustup update
       - name: Check
         run: cargo check --target wasm32-unknown-unknown --features esplora --no-default-features
 
@@ -144,5 +152,7 @@ jobs:
         run: rustup set profile minimal
       - name: Add clippy
         run: rustup component add rustfmt
+      - name: Update toolchain
+        run: rustup update
       - name: Check fmt
         run: cargo fmt --all -- --check

CHANGELOG.md

@@ -6,6 +6,35 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [v0.4.0] - [v0.3.0]
+
+### Keys
+#### Changed
+- Renamed `DerivableKey::add_metadata()` to `DerivableKey::into_descriptor_key()`
+- Renamed `ToDescriptorKey::to_descriptor_key()` to `IntoDescriptorKey::into_descriptor_key()`
+#### Added
+- Added an `ExtendedKey` type that is an enum of `bip32::ExtendedPubKey` and `bip32::ExtendedPrivKey`
+- Added `DerivableKey::into_extended_key()` as the only method that needs to be implemented
+
+### Misc
+#### Removed
+- Removed the `parse_descriptor` example, since it wasn't demonstrating any bdk-specific API anymore.
+#### Changed
+- Updated `bitcoin` to `0.26`, `miniscript` to `5.1` and `electrum-client` to `0.6`
+#### Added
+- Added support for the `signet` network (issue #62)
+- Added a function to get the version of BDK at runtime
+
+### Wallet
+#### Changed
+- Removed the explicit `id` argument from `Wallet::add_signer()` since that's now part of `Signer` itself
+- Renamed `ToWalletDescriptor::to_wallet_descriptor()` to `IntoWalletDescriptor::into_wallet_descriptor()`
+
+### Policy
+#### Changed
+- Removed unneeded `Result<(), PolicyError>` return type for `Satisfaction::finalize()`
+- Removed the `TooManyItemsSelected` policy error (see commit message for more details)
+
 ## [v0.3.0] - [v0.2.0]
 
 ### Descriptor
@@ -19,6 +48,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 #### Changed
 - Remove `BlockchainMarker`, `OfflineClient` and `OfflineWallet` in favor of just using the unit
   type to mark for a missing client.
+- Upgrade `tokio` to `1.0`.
+
+#### Transaction Creation Overhaul
+
+The `TxBuilder` is now created from the `build_tx` or `build_fee_bump` functions on wallet and the
+final transaction is created by calling `finish` on the builder.
+
+- Removed `TxBuilder::utxos` in favor of `TxBuilder::add_utxos`
+- Added `Wallet::build_tx` to replace `Wallet::create_tx`
+- Added `Wallet::build_fee_bump` to replace `Wallet::bump_fee`
+- Added `Wallet::get_utxo`
+- Added `Wallet::get_descriptor_for_keychain`
 
 ### CLI
 #### Changed
@@ -233,3 +274,4 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 [0.1.0-beta.1]: https://github.com/bitcoindevkit/bdk/compare/96c87ea5...0.1.0-beta.1
 [v0.2.0]: https://github.com/bitcoindevkit/bdk/compare/0.1.0-beta.1...v0.2.0
 [v0.3.0]: https://github.com/bitcoindevkit/bdk/compare/v0.2.0...v0.3.0
+[v0.4.0]: https://github.com/bitcoindevkit/bdk/compare/v0.3.0...v0.4.0

CONTRIBUTING.md

@@ -10,7 +10,7 @@ Anyone is invited to contribute without regard to technical experience,
 cryptocurrencies demands a high-level of rigor, adversarial thinking, thorough
 testing and risk-minimization.
 Any bug may cost users real money. That being said, we deeply welcome people
-contributing for the first time to an open source project or pick up Rust while
+contributing for the first time to an open source project or picking up Rust while
 contributing. Don't be shy, you'll learn.
 
 Communications Channels

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "bdk"
-version = "0.3.0"
+version = "0.4.0"
 edition = "2018"
 authors = ["Alekos Filini <alekos.filini@gmail.com>", "Riccardo Casatta <riccardo@casatta.it>"]
 homepage = "https://bitcoindevkit.org"
@@ -12,30 +12,29 @@ readme = "README.md"
 license = "MIT"
 
 [dependencies]
-bdk-macros = "0.2"
+bdk-macros = "^0.3"
 log = "^0.4"
-miniscript = "4.0"
-bitcoin = { version = "^0.25.2", features = ["use-serde"] }
+miniscript = "5.1"
+bitcoin = { version = "^0.26", features = ["use-serde"] }
 serde = { version = "^1.0", features = ["derive"] }
 serde_json = { version = "^1.0" }
 rand = "^0.7"
 
 # Optional dependencies
 sled = { version = "0.34", optional = true }
-electrum-client = { version = "0.5.0-beta.1", optional = true }
-reqwest = { version = "0.10", optional = true, features = ["json"] }
+electrum-client = { version = "0.6", optional = true }
+reqwest = { version = "0.11", optional = true, features = ["json"] }
 futures = { version = "0.3", optional = true }
 async-trait = { version = "0.1", optional = true }
 rocksdb = { version = "0.14", optional = true }
-# pin cc version to 1.0.62 because 1.0.63 break rocksdb build
-cc = { version = "=1.0.62", optional = true }
+cc = { version = ">=1.0.64", optional = true }
 socks = { version = "0.3", optional = true }
 lazy_static = { version = "1.4", optional = true }
 tiny-bip39 = { version = "^0.8", optional = true }
 
 # Platform-specific dependencies
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
-tokio = { version = "0.2", features = ["rt-core"] }
+tokio = { version = "1", features = ["rt"] }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 async-trait = "0.1"
@@ -60,18 +59,19 @@ test-electrum = ["electrum"]
 test-md-docs = ["electrum"]
 
 [dev-dependencies]
-bdk-testutils = "0.2"
-bdk-testutils-macros = "0.2"
+bdk-testutils = "^0.3"
+bdk-testutils-macros = "^0.3"
 serial_test = "0.4"
 lazy_static = "1.4"
 env_logger = "0.7"
 base64 = "^0.11"
 clap = "2.33"
 
-[[example]]
-name = "parse_descriptor"
 [[example]]
 name = "address_validator"
+[[example]]
+name = "compact_filters_balance"
+required-features = ["compact_filters"]
 
 [[example]]
 name = "miniscriptc"

DEVELOPMENT_CYCLE.md

@@ -1,15 +1,12 @@
 # Development Cycle
 
-This project follows a regular releasing schedule similar to the one [used by the Rust language](https://doc.rust-lang.org/book/appendix-07-nightly-rust.html). In short, this means that a new release is made at a regular
-cadence, with all the feature/bugfixes that made it to `master` in time. This ensures that we don't keep delaying releases waiting for "just one more little thing".
+This project follows a regular releasing schedule similar to the one [used by the Rust language](https://doc.rust-lang.org/book/appendix-07-nightly-rust.html). In short, this means that a new release is made at a regular cadence, with all the feature/bugfixes that made it to `master` in time. This ensures that we don't keep delaying releases waiting for "just one more little thing".
 
-We decided to maintain a faster release cycle while the library is still in "beta", i.e. before release `1.0.0`: since we are constantly adding new features and, even more importantly, fixing issues, we want developers
-to have access to those updates as fast as possible. For this reason we will make a release **every 4 weeks**.
+We decided to maintain a faster release cycle while the library is still in "beta", i.e. before release `1.0.0`: since we are constantly adding new features and, even more importantly, fixing issues, we want developers to have access to those updates as fast as possible. For this reason we will make a release **every 4 weeks**.
 
 Once the project will have reached a more mature state (>= `1.0.0`), we will very likely switch to longer release cycles of **6 weeks**.
 
-The "feature freeze" will happen **one week before the release date**. This means a new branch will be created originating from the `master` tip at that time, and in that branch we will stop adding new features and only focus
-on ensuring the ones we've added are working properly.
+The "feature freeze" will happen **one week before the release date**. This means a new branch will be created originating from the `master` tip at that time, and in that branch we will stop adding new features and only focus on ensuring the ones we've added are working properly.
 
 ```
 master:           - - - - * - - - * - - - - - - * - - - * ...
@@ -19,8 +16,7 @@ release/0.x.0:            * - - #               |       |
 release/0.y.0:                                  * - - #
 ```
 
-As soon as the release is tagged and published, the `release` branch will be merged back into `master` to update the version in the `Cargo.toml` to apply the new `Cargo.toml` version and all the other fixes made during the feature
-freeze window.
+As soon as the release is tagged and published, the `release` branch will be merged back into `master` to update the version in the `Cargo.toml` to apply the new `Cargo.toml` version and all the other fixes made during the feature freeze window.
 
 ## Making the Release
 
@@ -31,18 +27,19 @@ Pre-`v1.0.0` our "major" releases only affect the "minor" semver value. Accordin
 1. Create a new branch called `release/x.y.z` from `master`. Double check that your local `master` is up-to-date with the upstream repo before doing so.
 2. Make a commit on the release branch to bump the version to `x.y.z-rc.1`. The message should be "Bump version to x.y.z-rc.1".
 3. Push the new branch to `bitcoindevkit/bdk` on GitHub.
-4. During the one week of feature freeze run additional tests on the release branch
+4. During the one week of feature freeze run additional tests on the release branch.
 5. If a bug is found:
     - If it's a minor issue you can just fix it in the release branch, since it will be merged back to `master` eventually
     - For bigger issues you can fix them on `master` and then *cherry-pick* the commit to the release branch
-6. Update the changelog with the new release version
-7. On release day, make a commit on the release branch to bump the version to `x.y.z`. The message should be "Bump version to x.y.z".
-8. Add a tag to this commit. The tag name should be `vx.y.z` (for example `v0.5.0`), and the message "Release x.y.z". Make sure the tag is signed, for extra safety use the explicit `--sign` flag.
-9. Push the new commits to the upstream release branch, wait for the CI to finish one last time.
-10. Publish **all** the updated crates to crates.io.
-11. Make a new commit to bump the version value to `x.y.(z+1)-dev`. The message should be "Bump version to x.y.(z+1)-dev".
-12. Merge the release branch back into `master`.
-13. Create the release on GitHub: go to "tags", click on the dots on the right and select "Create Release". Then set the title to `vx.y.z` and write down some brief release notes.
-14. Make sure the new release shows up on crates.io and that the docs are built correctly on docs.rs.
-15. Announce the release on Twitter, Discord and Telegram.
-16. Celebrate :tada:
+6. Update the changelog with the new release version.
+7. Update `src/lib.rs` with the new version (line ~59)
+8. On release day, make a commit on the release branch to bump the version to `x.y.z`. The message should be "Bump version to x.y.z".
+9. Add a tag to this commit. The tag name should be `vx.y.z` (for example `v0.5.0`), and the message "Release x.y.z". Make sure the tag is signed, for extra safety use the explicit `--sign` flag.
+10. Push the new commits to the upstream release branch, wait for the CI to finish one last time.
+11. Publish **all** the updated crates to crates.io.
+12. Make a new commit to bump the version value to `x.y.(z+1)-dev`. The message should be "Bump version to x.y.(z+1)-dev".
+13. Merge the release branch back into `master`.
+14. Create the release on GitHub: go to "tags", click on the dots on the right and select "Create Release". Then set the title to `vx.y.z` and write down some brief release notes.
+15. Make sure the new release shows up on crates.io and that the docs are built correctly on docs.rs.
+16. Announce the release on Twitter, Discord and Telegram.
+17. Celebrate :tada:

README.md

@@ -87,7 +87,7 @@ fn main() -> Result<(), bdk::Error> {
 ### Create a transaction
 
 ```rust,no_run
-use bdk::{FeeRate, TxBuilder, Wallet};
+use bdk::{FeeRate, Wallet};
 use bdk::database::MemoryDatabase;
 use bdk::blockchain::{noop_progress, ElectrumBlockchain};
 
@@ -108,12 +108,15 @@ fn main() -> Result<(), bdk::Error> {
     wallet.sync(noop_progress(), None)?;
 
     let send_to = wallet.get_new_address()?;
-    let (psbt, details) = wallet.create_tx(
-        TxBuilder::with_recipients(vec![(send_to.script_pubkey(), 50_000)])
+    let (psbt, details) = {
+        let mut builder = wallet.build_tx();
+        builder
+            .add_recipient(send_to.script_pubkey(), 50_000)
             .enable_rbf()
             .do_not_spend_change()
-            .fee_rate(FeeRate::from_sat_per_vb(5.0))
-    )?;
+            .fee_rate(FeeRate::from_sat_per_vb(5.0));
+        builder.finish()?
+    };
 
     println!("Transaction details: {:#?}", details);
     println!("Unsigned PSBT: {}", base64::encode(&serialize(&psbt)));

examples/address_validator.rs

@@ -35,6 +35,7 @@ use bitcoin::hashes::hex::FromHex;
 use bitcoin::util::bip32::Fingerprint;
 use bitcoin::{Network, Script};
 
+#[derive(Debug)]
 struct DummyValidator;
 impl AddressValidator for DummyValidator {
     fn validate(

examples/compact_filters_balance.rs

@@ -0,0 +1,32 @@
+use bdk::blockchain::compact_filters::*;
+use bdk::blockchain::noop_progress;
+use bdk::database::MemoryDatabase;
+use bdk::*;
+use bitcoin::*;
+use blockchain::compact_filters::CompactFiltersBlockchain;
+use blockchain::compact_filters::CompactFiltersError;
+use log::info;
+use std::sync::Arc;
+
+/// This will return wallet balance using compact filters
+/// Requires a synced local bitcoin node 0.21 running on testnet with blockfilterindex=1 and peerblockfilters=1
+fn main() -> Result<(), CompactFiltersError> {
+    env_logger::init();
+    info!("start");
+
+    let num_threads = 4;
+    let mempool = Arc::new(Mempool::default());
+    let peers = (0..num_threads)
+        .map(|_| Peer::connect("localhost:18333", Arc::clone(&mempool), Network::Testnet))
+        .collect::<Result<_, _>>()?;
+    let blockchain = CompactFiltersBlockchain::new(peers, "./wallet-filters", Some(500_000))?;
+    info!("done {:?}", blockchain);
+    let descriptor = "wpkh(tpubD6NzVbkrYhZ4X2yy78HWrr1M9NT8dKeWfzNiQqDdMqqa9UmmGztGGz6TaLFGsLfdft5iu32gxq1T4eMNxExNNWzVCpf9Y6JZi5TnqoC9wJq/*)";
+
+    let database = MemoryDatabase::default();
+    let wallet =
+        Arc::new(Wallet::new(descriptor, None, Network::Testnet, database, blockchain).unwrap());
+    wallet.sync(noop_progress(), None).unwrap();
+    info!("balance: {}", wallet.get_balance()?);
+    Ok(())
+}

examples/compiler.rs

@@ -29,6 +29,7 @@ extern crate log;
 extern crate miniscript;
 extern crate serde_json;
 
+use std::error::Error;
 use std::str::FromStr;
 
 use log::info;
@@ -42,7 +43,7 @@ use miniscript::Descriptor;
 use bdk::database::memory::MemoryDatabase;
 use bdk::{KeychainKind, Wallet};
 
-fn main() {
+fn main() -> Result<(), Box<dyn Error>> {
     env_logger::init_from_env(
         env_logger::Env::default().filter_or(env_logger::DEFAULT_FILTER_ENV, "info"),
     );
@@ -74,19 +75,19 @@ fn main() {
                 .help("Sets the network")
                 .takes_value(true)
                 .default_value("testnet")
-                .possible_values(&["testnet", "regtest"]),
+                .possible_values(&["testnet", "regtest", "bitcoin", "signet"]),
         )
         .get_matches();
 
     let policy_str = matches.value_of("POLICY").unwrap();
     info!("Compiling policy: {}", policy_str);
 
-    let policy = Concrete::<String>::from_str(&policy_str).unwrap();
+    let policy = Concrete::<String>::from_str(&policy_str)?;
 
     let descriptor = match matches.value_of("TYPE").unwrap() {
-        "sh" => Descriptor::Sh(policy.compile().unwrap()),
-        "wsh" => Descriptor::Wsh(policy.compile().unwrap()),
-        "sh-wsh" => Descriptor::ShWsh(policy.compile().unwrap()),
+        "sh" => Descriptor::new_sh(policy.compile()?)?,
+        "wsh" => Descriptor::new_wsh(policy.compile()?)?,
+        "sh-wsh" => Descriptor::new_sh_wsh(policy.compile()?)?,
         _ => panic!("Invalid type"),
     };
 
@@ -94,19 +95,23 @@ fn main() {
 
     let database = MemoryDatabase::new();
 
-    let network = match matches.value_of("network") {
-        Some("regtest") => Network::Regtest,
-        Some("testnet") | _ => Network::Testnet,
-    };
-    let wallet = Wallet::new_offline(&format!("{}", descriptor), None, network, database).unwrap();
+    let network = matches
+        .value_of("network")
+        .and_then(|n| Some(Network::from_str(n)))
+        .transpose()
+        .unwrap()
+        .unwrap_or(Network::Testnet);
+    let wallet = Wallet::new_offline(&format!("{}", descriptor), None, network, database)?;
 
-    info!("... First address: {}", wallet.get_new_address().unwrap());
+    info!("... First address: {}", wallet.get_new_address()?);
 
     if matches.is_present("parsed_policy") {
-        let spending_policy = wallet.policies(KeychainKind::External).unwrap();
+        let spending_policy = wallet.policies(KeychainKind::External)?;
         info!(
             "... Spending policy:\n{}",
-            serde_json::to_string_pretty(&spending_policy).unwrap()
+            serde_json::to_string_pretty(&spending_policy)?
         );
     }
+
+    Ok(())
 }

examples/parse_descriptor.rs

@@ -1,60 +0,0 @@
-// Magical Bitcoin Library
-// Written in 2020 by
-//     Alekos Filini <alekos.filini@gmail.com>
-//
-// Copyright (c) 2020 Magical Bitcoin
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in all
-// copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-// SOFTWARE.
-
-extern crate bdk;
-extern crate serde_json;
-
-use std::sync::Arc;
-
-use bdk::bitcoin::secp256k1::Secp256k1;
-use bdk::bitcoin::util::bip32::ChildNumber;
-use bdk::bitcoin::*;
-use bdk::descriptor::*;
-use bdk::miniscript::DescriptorPublicKeyCtx;
-
-fn main() {
-    let secp = Secp256k1::new();
-
-    let desc = "wsh(or_d(\
-                    multi(\
-                      2,[d34db33f/44'/0'/0']xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL/1/*,tprv8ZgxMBicQKsPduL5QnGihpprdHyypMGi4DhimjtzYemu7se5YQNcZfAPLqXRuGHb5ZX2eTQj62oNqMnyxJ7B7wz54Uzswqw8fFqMVdcmVF7/1/*\
-                    ),\
-                    and_v(vc:pk_h(cVt4o7BGAig1UXywgGSmARhxMdzP5qvQsxKkSsc1XEkw3tDTQFpy),older(1000))\
-                   ))";
-
-    let (extended_desc, key_map) = ExtendedDescriptor::parse_descriptor(desc).unwrap();
-    println!("{:?}", extended_desc);
-
-    let deriv_ctx = DescriptorPublicKeyCtx::new(&secp, ChildNumber::from_normal_idx(42).unwrap());
-
-    let signers = Arc::new(key_map.into());
-    let policy = extended_desc.extract_policy(&signers, &secp).unwrap();
-    println!("policy: {}", serde_json::to_string(&policy).unwrap());
-
-    let addr = extended_desc.address(Network::Testnet, deriv_ctx).unwrap();
-    println!("{}", addr);
-
-    let script = extended_desc.witness_script(deriv_ctx);
-    println!("{:?}", script);
-}

macros/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "bdk-macros"
-version = "0.2.0"
+version = "0.3.0"
 authors = ["Alekos Filini <alekos.filini@gmail.com>"]
 edition = "2018"
 homepage = "https://bitcoindevkit.org"

macros/src/lib.rs

@@ -145,7 +145,7 @@ pub fn await_or_block(expr: TokenStream) -> TokenStream {
         {
             #[cfg(all(not(target_arch = "wasm32"), not(feature = "async-interface")))]
             {
-                tokio::runtime::Runtime::new().unwrap().block_on(#expr)
+                tokio::runtime::Builder::new_current_thread().enable_all().build().unwrap().block_on(#expr)
             }
 
             #[cfg(any(target_arch = "wasm32", feature = "async-interface"))]

src/blockchain/compact_filters/mod.rs

@@ -383,7 +383,12 @@ impl Blockchain for CompactFiltersBlockchain {
         }
         database.commit_batch(updates)?;
 
-        first_peer.ask_for_mempool()?;
+        match first_peer.ask_for_mempool() {
+            Err(CompactFiltersError::PeerBloomDisabled) => {
+                log::warn!("Peer has BLOOM disabled, we can't ask for the mempool")
+            }
+            e => e?,
+        };
 
         let mut internal_max_deriv = None;
         let mut external_max_deriv = None;
@@ -537,6 +542,8 @@ pub enum CompactFiltersError {
     NotConnected,
     /// A peer took too long to reply to one of our messages
     Timeout,
+    /// The peer doesn't advertise the [`BLOOM`](bitcoin::network::constants::ServiceFlags::BLOOM) service flag
+    PeerBloomDisabled,
 
     /// No peers have been specified
     NoPeers,

src/blockchain/compact_filters/peer.rs

@@ -34,7 +34,6 @@ use rand::{thread_rng, Rng};
 
 use bitcoin::consensus::Encodable;
 use bitcoin::hash_types::BlockHash;
-use bitcoin::hashes::Hash;
 use bitcoin::network::constants::ServiceFlags;
 use bitcoin::network::message::{NetworkMessage, RawNetworkMessage};
 use bitcoin::network::message_blockdata::*;
@@ -42,7 +41,7 @@ use bitcoin::network::message_filter::*;
 use bitcoin::network::message_network::VersionMessage;
 use bitcoin::network::stream_reader::StreamReader;
 use bitcoin::network::Address;
-use bitcoin::{Block, Network, Transaction, Txid};
+use bitcoin::{Block, Network, Transaction, Txid, Wtxid};
 
 use super::CompactFiltersError;
 
@@ -55,37 +54,71 @@ pub(crate) const TIMEOUT_SECS: u64 = 30;
 /// It is normally shared between [`Peer`]s with the use of [`Arc`], so that transactions are not
 /// duplicated in memory.
 #[derive(Debug, Default)]
-pub struct Mempool {
-    txs: RwLock<HashMap<Txid, Transaction>>,
+pub struct Mempool(RwLock<InnerMempool>);
+
+#[derive(Debug, Default)]
+struct InnerMempool {
+    txs: HashMap<Txid, Transaction>,
+    wtxids: HashMap<Wtxid, Txid>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+enum TxIdentifier {
+    Wtxid(Wtxid),
+    Txid(Txid),
 }
 
 impl Mempool {
+    /// Create a new empty mempool
+    pub fn new() -> Self {
+        Self::default()
+    }
+
     /// Add a transaction to the mempool
     ///
     /// Note that this doesn't propagate the transaction to other
     /// peers. To do that, [`broadcast`](crate::blockchain::Blockchain::broadcast) should be used.
     pub fn add_tx(&self, tx: Transaction) {
-        self.txs.write().unwrap().insert(tx.txid(), tx);
+        let mut guard = self.0.write().unwrap();
+
+        guard.wtxids.insert(tx.wtxid(), tx.txid());
+        guard.txs.insert(tx.txid(), tx);
     }
 
     /// Look-up a transaction in the mempool given an [`Inventory`] request
     pub fn get_tx(&self, inventory: &Inventory) -> Option<Transaction> {
-        let txid = match inventory {
+        let identifer = match inventory {
             Inventory::Error | Inventory::Block(_) | Inventory::WitnessBlock(_) => return None,
-            Inventory::Transaction(txid) => *txid,
-            Inventory::WitnessTransaction(wtxid) => Txid::from_inner(wtxid.into_inner()),
+            Inventory::Transaction(txid) => TxIdentifier::Txid(*txid),
+            Inventory::WitnessTransaction(txid) => TxIdentifier::Txid(*txid),
+            Inventory::WTx(wtxid) => TxIdentifier::Wtxid(*wtxid),
+            Inventory::Unknown { inv_type, hash } => {
+                log::warn!(
+                    "Unknown inventory request type `{}`, hash `{:?}`",
+                    inv_type,
+                    hash
+                );
+                return None;
+            }
         };
-        self.txs.read().unwrap().get(&txid).cloned()
+
+        let txid = match identifer {
+            TxIdentifier::Txid(txid) => Some(txid),
+            TxIdentifier::Wtxid(wtxid) => self.0.read().unwrap().wtxids.get(&wtxid).cloned(),
+        };
+
+        txid.map(|txid| self.0.read().unwrap().txs.get(&txid).cloned())
+            .flatten()
     }
 
     /// Return whether or not the mempool contains a transaction with a given txid
     pub fn has_tx(&self, txid: &Txid) -> bool {
-        self.txs.read().unwrap().contains_key(txid)
+        self.0.read().unwrap().txs.contains_key(txid)
     }
 
     /// Return the list of transactions contained in the mempool
     pub fn iter_txs(&self) -> Vec<Transaction> {
-        self.txs.read().unwrap().values().cloned().collect()
+        self.0.read().unwrap().txs.values().cloned().collect()
     }
 }
 
@@ -190,14 +223,14 @@ impl Peer {
             )),
         )?;
         let version = if let NetworkMessage::Version(version) =
-            Self::_recv(&responses, "version", None)?.unwrap()
+            Self::_recv(&responses, "version", None).unwrap()
         {
             version
         } else {
             return Err(CompactFiltersError::InvalidResponse);
         };
 
-        if let NetworkMessage::Verack = Self::_recv(&responses, "verack", None)?.unwrap() {
+        if let NetworkMessage::Verack = Self::_recv(&responses, "verack", None).unwrap() {
             Self::_send(&mut locked_writer, network.magic(), NetworkMessage::Verack)?;
         } else {
             return Err(CompactFiltersError::InvalidResponse);
@@ -238,7 +271,7 @@ impl Peer {
         responses: &Arc<RwLock<ResponsesMap>>,
         wait_for: &'static str,
         timeout: Option<Duration>,
-    ) -> Result<Option<NetworkMessage>, CompactFiltersError> {
+    ) -> Option<NetworkMessage> {
         let message_resp = {
             let mut lock = responses.write().unwrap();
             let message_resp = lock.entry(wait_for).or_default();
@@ -254,15 +287,14 @@ impl Peer {
                 Some(t) => {
                     let result = cvar.wait_timeout(messages, t).unwrap();
                     if result.1.timed_out() {
-                        return Ok(None);
+                        return None;
                     }
-
                     messages = result.0;
                 }
             }
         }
 
-        Ok(messages.pop())
+        messages.pop()
     }
 
     /// Return the [`VersionMessage`] sent by the peer
@@ -382,7 +414,7 @@ impl Peer {
         wait_for: &'static str,
         timeout: Option<Duration>,
     ) -> Result<Option<NetworkMessage>, CompactFiltersError> {
-        Self::_recv(&self.responses, wait_for, timeout)
+        Ok(Self::_recv(&self.responses, wait_for, timeout))
     }
 }
 
@@ -508,6 +540,10 @@ impl InvPeer for Peer {
     }
 
     fn ask_for_mempool(&self) -> Result<(), CompactFiltersError> {
+        if !self.version.services.has(ServiceFlags::BLOOM) {
+            return Err(CompactFiltersError::PeerBloomDisabled);
+        }
+
         self.send(NetworkMessage::MemPool)?;
         let inv = match self.recv("inv", Some(Duration::from_secs(5)))? {
             None => return Ok(()), // empty mempool

src/blockchain/compact_filters/store.rs

@@ -36,9 +36,9 @@ use rand::{thread_rng, Rng};
 use rocksdb::{Direction, IteratorMode, ReadOptions, WriteBatch, DB};
 
 use bitcoin::consensus::{deserialize, encode::VarInt, serialize, Decodable, Encodable};
-use bitcoin::hash_types::FilterHash;
+use bitcoin::hash_types::{FilterHash, FilterHeader};
 use bitcoin::hashes::hex::FromHex;
-use bitcoin::hashes::{sha256d, Hash};
+use bitcoin::hashes::Hash;
 use bitcoin::util::bip158::BlockFilter;
 use bitcoin::util::uint::Uint256;
 use bitcoin::Block;
@@ -52,6 +52,7 @@ lazy_static! {
     static ref MAINNET_GENESIS: Block = deserialize(&Vec::<u8>::from_hex("0100000000000000000000000000000000000000000000000000000000000000000000003BA3EDFD7A7B12B27AC72C3E67768F617FC81BC3888A51323A9FB8AA4B1E5E4A29AB5F49FFFF001D1DAC2B7C0101000000010000000000000000000000000000000000000000000000000000000000000000FFFFFFFF4D04FFFF001D0104455468652054696D65732030332F4A616E2F32303039204368616E63656C6C6F72206F6E206272696E6B206F66207365636F6E64206261696C6F757420666F722062616E6B73FFFFFFFF0100F2052A01000000434104678AFDB0FE5548271967F1A67130B7105CD6A828E03909A67962E0EA1F61DEB649F6BC3F4CEF38C4F35504E51EC112DE5C384DF7BA0B8D578A4C702B6BF11D5FAC00000000").unwrap()).unwrap();
     static ref TESTNET_GENESIS: Block = deserialize(&Vec::<u8>::from_hex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unwrap()).unwrap();
     static ref REGTEST_GENESIS: Block = deserialize(&Vec::<u8>::from_hex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unwrap()).unwrap();
+    static ref SIGNET_GENESIS: Block = deserialize(&Vec::<u8>::from_hex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unwrap()).unwrap();
 }
 
 pub trait StoreType: Default + fmt::Debug {}
@@ -122,34 +123,8 @@ where
     }
 }
 
-impl Encodable for FilterHeader {
-    fn consensus_encode<W: Write>(
-        &self,
-        mut e: W,
-    ) -> Result<usize, bitcoin::consensus::encode::Error> {
-        let mut written = self.prev_header_hash.consensus_encode(&mut e)?;
-        written += self.filter_hash.consensus_encode(&mut e)?;
-        Ok(written)
-    }
-}
-
-impl Decodable for FilterHeader {
-    fn consensus_decode<D: Read>(mut d: D) -> Result<Self, bitcoin::consensus::encode::Error> {
-        let prev_header_hash = FilterHeaderHash::consensus_decode(&mut d)?;
-        let filter_hash = FilterHash::consensus_decode(&mut d)?;
-
-        Ok(FilterHeader {
-            prev_header_hash,
-            filter_hash,
-        })
-    }
-}
-
 impl Encodable for BundleStatus {
-    fn consensus_encode<W: Write>(
-        &self,
-        mut e: W,
-    ) -> Result<usize, bitcoin::consensus::encode::Error> {
+    fn consensus_encode<W: Write>(&self, mut e: W) -> Result<usize, std::io::Error> {
         let mut written = 0;
 
         match self {
@@ -264,6 +239,7 @@ impl ChainStore<Full> {
             Network::Bitcoin => MAINNET_GENESIS.deref(),
             Network::Testnet => TESTNET_GENESIS.deref(),
             Network::Regtest => REGTEST_GENESIS.deref(),
+            Network::Signet => SIGNET_GENESIS.deref(),
         };
 
         let cf_name = "default".to_string();
@@ -658,22 +634,6 @@ impl<T: StoreType> fmt::Debug for ChainStore<T> {
     }
 }
 
-pub type FilterHeaderHash = FilterHash;
-
-#[derive(Debug, Clone)]
-pub struct FilterHeader {
-    prev_header_hash: FilterHeaderHash,
-    filter_hash: FilterHash,
-}
-
-impl FilterHeader {
-    fn header_hash(&self) -> FilterHeaderHash {
-        let mut hash_data = self.filter_hash.into_inner().to_vec();
-        hash_data.extend_from_slice(&self.prev_header_hash);
-        sha256d::Hash::hash(&hash_data).into()
-    }
-}
-
 pub enum BundleStatus {
     Init,
     CFHeaders { cf_headers: Vec<FilterHeader> },
@@ -688,7 +648,7 @@ pub struct CFStore {
     filter_type: u8,
 }
 
-type BundleEntry = (BundleStatus, FilterHeaderHash);
+type BundleEntry = (BundleStatus, FilterHeader);
 
 impl CFStore {
     pub fn new(
@@ -704,6 +664,7 @@ impl CFStore {
             Network::Bitcoin => MAINNET_GENESIS.deref(),
             Network::Testnet => TESTNET_GENESIS.deref(),
             Network::Regtest => REGTEST_GENESIS.deref(),
+            Network::Signet => SIGNET_GENESIS.deref(),
         };
 
         let filter = BlockFilter::new_script_filter(genesis, |utxo| {
@@ -717,7 +678,11 @@ impl CFStore {
             if read_store.get_pinned(&first_key)?.is_none() {
                 read_store.put(
                     &first_key,
-                    (BundleStatus::Init, filter.filter_id(&FilterHash::default())).serialize(),
+                    (
+                        BundleStatus::Init,
+                        filter.filter_header(&FilterHeader::from_hash(Default::default())),
+                    )
+                        .serialize(),
                 )?;
             }
         }
@@ -743,7 +708,7 @@ impl CFStore {
             .collect::<Result<_, _>>()
     }
 
-    pub fn get_checkpoints(&self) -> Result<Vec<FilterHash>, CompactFiltersError> {
+    pub fn get_checkpoints(&self) -> Result<Vec<FilterHeader>, CompactFiltersError> {
         let read_store = self.store.read().unwrap();
 
         let prefix = StoreEntry::CFilterTable((self.filter_type, None)).get_key();
@@ -760,7 +725,7 @@ impl CFStore {
 
     pub fn replace_checkpoints(
         &self,
-        checkpoints: Vec<FilterHash>,
+        checkpoints: Vec<FilterHeader>,
     ) -> Result<(), CompactFiltersError> {
         let current_checkpoints = self.get_checkpoints()?;
 
@@ -802,20 +767,16 @@ impl CFStore {
     pub fn advance_to_cf_headers(
         &self,
         bundle: usize,
-        checkpoint_hash: FilterHeaderHash,
-        filter_headers: Vec<FilterHash>,
+        checkpoint: FilterHeader,
+        filter_hashes: Vec<FilterHash>,
     ) -> Result<BundleStatus, CompactFiltersError> {
-        let mut last_hash = checkpoint_hash;
-        let cf_headers = filter_headers
+        let cf_headers: Vec<FilterHeader> = filter_hashes
             .into_iter()
-            .map(|filter_hash| {
-                let filter_header = FilterHeader {
-                    prev_header_hash: last_hash,
-                    filter_hash,
-                };
-                last_hash = filter_header.header_hash();
+            .scan(checkpoint, |prev_header, filter_hash| {
+                let filter_header = filter_hash.filter_header(&prev_header);
+                *prev_header = filter_header;
 
-                filter_header
+                Some(filter_header)
             })
             .collect();
 
@@ -828,13 +789,13 @@ impl CFStore {
             .transpose()?
         {
             // check connection with the next bundle if present
-            if last_hash != next_checkpoint {
+            if cf_headers.iter().last() != Some(&next_checkpoint) {
                 return Err(CompactFiltersError::InvalidFilterHeader);
             }
         }
 
         let key = StoreEntry::CFilterTable((self.filter_type, Some(bundle))).get_key();
-        let value = (BundleStatus::CFHeaders { cf_headers }, checkpoint_hash);
+        let value = (BundleStatus::CFHeaders { cf_headers }, checkpoint);
 
         read_store.put(key, value.serialize())?;
 
@@ -844,24 +805,26 @@ impl CFStore {
     pub fn advance_to_cf_filters(
         &self,
         bundle: usize,
-        checkpoint_hash: FilterHeaderHash,
+        checkpoint: FilterHeader,
         headers: Vec<FilterHeader>,
         filters: Vec<(usize, Vec<u8>)>,
     ) -> Result<BundleStatus, CompactFiltersError> {
         let cf_filters = filters
             .into_iter()
-            .zip(headers.iter())
-            .map(|((_, filter_content), header)| {
-                if header.filter_hash != sha256d::Hash::hash(&filter_content).into() {
-                    return Err(CompactFiltersError::InvalidFilter);
+            .zip(headers.into_iter())
+            .scan(checkpoint, |prev_header, ((_, filter_content), header)| {
+                let filter = BlockFilter::new(&filter_content);
+                if header != filter.filter_header(&prev_header) {
+                    return Some(Err(CompactFiltersError::InvalidFilter));
                 }
+                *prev_header = header;
 
-                Ok::<_, CompactFiltersError>(filter_content)
+                Some(Ok::<_, CompactFiltersError>(filter_content))
             })
             .collect::<Result<_, _>>()?;
 
         let key = StoreEntry::CFilterTable((self.filter_type, Some(bundle))).get_key();
-        let value = (BundleStatus::CFilters { cf_filters }, checkpoint_hash);
+        let value = (BundleStatus::CFilters { cf_filters }, checkpoint);
 
         let read_store = self.store.read().unwrap();
         read_store.put(key, value.serialize())?;
@@ -872,10 +835,10 @@ impl CFStore {
     pub fn prune_filters(
         &self,
         bundle: usize,
-        checkpoint_hash: FilterHeaderHash,
+        checkpoint: FilterHeader,
     ) -> Result<BundleStatus, CompactFiltersError> {
         let key = StoreEntry::CFilterTable((self.filter_type, Some(bundle))).get_key();
-        let value = (BundleStatus::Pruned, checkpoint_hash);
+        let value = (BundleStatus::Pruned, checkpoint);
 
         let read_store = self.store.read().unwrap();
         read_store.put(key, value.serialize())?;
@@ -887,10 +850,10 @@ impl CFStore {
         &self,
         bundle: usize,
         cf_filters: Vec<Vec<u8>>,
-        checkpoint_hash: FilterHeaderHash,
+        checkpoint: FilterHeader,
     ) -> Result<BundleStatus, CompactFiltersError> {
         let key = StoreEntry::CFilterTable((self.filter_type, Some(bundle))).get_key();
-        let value = (BundleStatus::Tip { cf_filters }, checkpoint_hash);
+        let value = (BundleStatus::Tip { cf_filters }, checkpoint);
 
         let read_store = self.store.read().unwrap();
         read_store.put(key, value.serialize())?;

src/blockchain/compact_filters/sync.rs

@@ -26,7 +26,7 @@ use std::collections::{BTreeMap, HashMap, VecDeque};
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
-use bitcoin::hash_types::{BlockHash, FilterHash};
+use bitcoin::hash_types::{BlockHash, FilterHeader};
 use bitcoin::network::message::NetworkMessage;
 use bitcoin::network::message_blockdata::GetHeadersMessage;
 use bitcoin::util::bip158::BlockFilter;
@@ -42,7 +42,7 @@ pub struct CFSync {
     headers_store: Arc<ChainStore<Full>>,
     cf_store: Arc<CFStore>,
     skip_blocks: usize,
-    bundles: Mutex<VecDeque<(BundleStatus, FilterHash, usize)>>,
+    bundles: Mutex<VecDeque<(BundleStatus, FilterHeader, usize)>>,
 }
 
 impl CFSync {
@@ -148,7 +148,7 @@ impl CFSync {
 
                 let resp = peer.get_cf_headers(0x00, start_height as u32, stop_hash)?;
 
-                assert!(resp.previous_filter == checkpoint);
+                assert!(resp.previous_filter_header == checkpoint);
                 status =
                     self.cf_store
                         .advance_to_cf_headers(index, checkpoint, resp.filter_hashes)?;

src/database/memory.rs

@@ -458,16 +458,17 @@ impl ConfigurableDatabase for MemoryDatabase {
     }
 }
 
-#[cfg(test)]
-impl MemoryDatabase {
-    // Artificially insert a tx in the database, as if we had found it with a `sync`
-    pub fn received_tx(
-        &mut self,
-        tx_meta: testutils::TestIncomingTx,
-        current_height: Option<u32>,
-    ) -> bitcoin::Txid {
-        use std::str::FromStr;
-
+#[macro_export]
+#[doc(hidden)]
+/// Artificially insert a tx in the database, as if we had found it with a `sync`. This is a hidden
+/// macro and not a `[cfg(test)]` function so it can be called within the context of doctests which
+/// don't have `test` set.
+macro_rules! populate_test_db {
+    ($db:expr, $tx_meta:expr, $current_height:expr$(,)?) => {{
+        use $crate::database::BatchOperations;
+        let mut db = $db;
+        let tx_meta = $tx_meta;
+        let current_height: Option<u32> = $current_height;
         let tx = Transaction {
             version: 1,
             lock_time: 0,
@@ -499,9 +500,9 @@ impl MemoryDatabase {
             fees: 0,
         };
 
-        self.set_tx(&tx_details).unwrap();
+        db.set_tx(&tx_details).unwrap();
         for (vout, out) in tx.output.iter().enumerate() {
-            self.set_utxo(&UTXO {
+            db.set_utxo(&UTXO {
                 txout: out.clone(),
                 outpoint: OutPoint {
                     txid,
@@ -513,7 +514,37 @@ impl MemoryDatabase {
         }
 
         txid
-    }
+    }};
+}
+
+#[macro_export]
+#[doc(hidden)]
+/// Macro for getting a wallet for use in a doctest
+macro_rules! doctest_wallet {
+    () => {{
+        use $crate::bitcoin::Network;
+        use $crate::database::MemoryDatabase;
+        use testutils::testutils;
+        let descriptor = "wpkh(cVpPVruEDdmutPzisEsYvtST1usBR3ntr8pXSyt6D2YYqXRyPcFW)";
+        let descriptors = testutils!(@descriptors (descriptor) (descriptor));
+
+        let mut db = MemoryDatabase::new();
+        let txid = populate_test_db!(
+            &mut db,
+            testutils! {
+                @tx ( (@external descriptors, 0) => 500_000 ) (@confirmations 1)
+            },
+            Some(100),
+        );
+
+        $crate::Wallet::new_offline(
+            &descriptors.0,
+            descriptors.1.as_ref(),
+            Network::Regtest,
+            db
+        )
+        .unwrap()
+    }}
 }
 
 #[cfg(test)]

src/descriptor/derived.rs

@@ -0,0 +1,163 @@
+// Magical Bitcoin Library
+// Written in 2020 by
+//     Alekos Filini <alekos.filini@gmail.com>
+//
+// Copyright (c) 2020 Magical Bitcoin
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+//! Derived descriptor keys
+
+use std::cmp::Ordering;
+use std::fmt;
+use std::hash::{Hash, Hasher};
+use std::ops::Deref;
+
+use bitcoin::hashes::hash160;
+use bitcoin::PublicKey;
+
+pub use miniscript::{
+    descriptor::KeyMap, descriptor::Wildcard, Descriptor, DescriptorPublicKey, Legacy, Miniscript,
+    ScriptContext, Segwitv0,
+};
+use miniscript::{MiniscriptKey, ToPublicKey, TranslatePk};
+
+use crate::wallet::utils::SecpCtx;
+
+/// Extended [`DescriptorPublicKey`] that has been derived
+///
+/// Derived keys are guaranteed to never contain wildcards of any kind
+#[derive(Debug, Clone)]
+pub struct DerivedDescriptorKey<'s>(DescriptorPublicKey, &'s SecpCtx);
+
+impl<'s> DerivedDescriptorKey<'s> {
+    /// Construct a new derived key
+    ///
+    /// Panics if the key is wildcard
+    pub fn new(key: DescriptorPublicKey, secp: &'s SecpCtx) -> DerivedDescriptorKey<'s> {
+        if let DescriptorPublicKey::XPub(xpub) = &key {
+            assert!(xpub.wildcard == Wildcard::None)
+        }
+
+        DerivedDescriptorKey(key, secp)
+    }
+}
+
+impl<'s> Deref for DerivedDescriptorKey<'s> {
+    type Target = DescriptorPublicKey;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl<'s> PartialEq for DerivedDescriptorKey<'s> {
+    fn eq(&self, other: &Self) -> bool {
+        self.0 == other.0
+    }
+}
+
+impl<'s> Eq for DerivedDescriptorKey<'s> {}
+
+impl<'s> PartialOrd for DerivedDescriptorKey<'s> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        self.0.partial_cmp(&other.0)
+    }
+}
+
+impl<'s> Ord for DerivedDescriptorKey<'s> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.0.cmp(&other.0)
+    }
+}
+
+impl<'s> fmt::Display for DerivedDescriptorKey<'s> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}
+
+impl<'s> Hash for DerivedDescriptorKey<'s> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.0.hash(state);
+    }
+}
+
+impl<'s> MiniscriptKey for DerivedDescriptorKey<'s> {
+    type Hash = Self;
+
+    fn to_pubkeyhash(&self) -> Self::Hash {
+        DerivedDescriptorKey(self.0.to_pubkeyhash(), self.1)
+    }
+
+    fn is_uncompressed(&self) -> bool {
+        self.0.is_uncompressed()
+    }
+    fn serialized_len(&self) -> usize {
+        self.0.serialized_len()
+    }
+}
+
+impl<'s> ToPublicKey for DerivedDescriptorKey<'s> {
+    fn to_public_key(&self) -> PublicKey {
+        match &self.0 {
+            DescriptorPublicKey::SinglePub(ref spub) => spub.key.to_public_key(),
+            DescriptorPublicKey::XPub(ref xpub) => {
+                xpub.xkey
+                    .derive_pub(self.1, &xpub.derivation_path)
+                    .expect("Shouldn't fail, only normal derivations")
+                    .public_key
+            }
+        }
+    }
+
+    fn hash_to_hash160(hash: &Self::Hash) -> hash160::Hash {
+        hash.to_public_key().to_pubkeyhash()
+    }
+}
+
+pub(crate) trait AsDerived {
+    // Derive a descriptor and transform all of its keys to `DerivedDescriptorKey`
+    fn as_derived<'s>(&self, index: u32, secp: &'s SecpCtx)
+        -> Descriptor<DerivedDescriptorKey<'s>>;
+
+    // Transform the keys into `DerivedDescriptorKey`.
+    //
+    // Panics if the descriptor is not "fixed", i.e. if it's derivable
+    fn as_derived_fixed<'s>(&self, secp: &'s SecpCtx) -> Descriptor<DerivedDescriptorKey<'s>>;
+}
+
+impl AsDerived for Descriptor<DescriptorPublicKey> {
+    fn as_derived<'s>(
+        &self,
+        index: u32,
+        secp: &'s SecpCtx,
+    ) -> Descriptor<DerivedDescriptorKey<'s>> {
+        self.derive(index).translate_pk_infallible(
+            |key| DerivedDescriptorKey::new(key.clone(), secp),
+            |key| DerivedDescriptorKey::new(key.clone(), secp),
+        )
+    }
+
+    fn as_derived_fixed<'s>(&self, secp: &'s SecpCtx) -> Descriptor<DerivedDescriptorKey<'s>> {
+        assert!(!self.is_deriveable());
+
+        self.as_derived(0, secp)
+    }
+}

src/descriptor/dsl.rs

@@ -28,48 +28,61 @@
 #[macro_export]
 macro_rules! impl_top_level_sh {
     // disallow `sortedmulti` in `bare()`
-    ( Bare, Bare, sortedmulti $( $inner:tt )* ) => {
+    ( Bare, new, new, Legacy, sortedmulti $( $inner:tt )* ) => {
         compile_error!("`bare()` descriptors can't contain any `sortedmulti()` operands");
     };
-    ( Bare, Bare, sortedmulti_vec $( $inner:tt )* ) => {
+    ( Bare, new, new, Legacy, sortedmulti_vec $( $inner:tt )* ) => {
         compile_error!("`bare()` descriptors can't contain any `sortedmulti_vec()` operands");
     };
 
-    ( $descriptor_variant:ident, $sortedmulti_variant:ident, sortedmulti $( $inner:tt )* ) => {
-        $crate::impl_sortedmulti!(sortedmulti $( $inner )*)
-            .and_then(|(inner, key_map, valid_networks)| Ok(($crate::miniscript::Descriptor::$sortedmulti_variant(inner), key_map, valid_networks)))
-    };
-    ( $descriptor_variant:ident, $sortedmulti_variant:ident, sortedmulti_vec $( $inner:tt )* ) => {
-        $crate::impl_sortedmulti!(sortedmulti_vec $( $inner )*)
-            .and_then(|(inner, key_map, valid_networks)| Ok(($crate::miniscript::Descriptor::$sortedmulti_variant(inner), key_map, valid_networks)))
-    };
+    ( $inner_struct:ident, $constructor:ident, $sortedmulti_constructor:ident, $ctx:ident, sortedmulti $( $inner:tt )* ) => {{
+        use std::marker::PhantomData;
+
+        use $crate::miniscript::descriptor::{$inner_struct, Descriptor, DescriptorPublicKey};
+        use $crate::miniscript::$ctx;
+
+        let build_desc = |k, pks| {
+            Ok((Descriptor::<DescriptorPublicKey>::$inner_struct($inner_struct::$sortedmulti_constructor(k, pks)?), PhantomData::<$ctx>))
+        };
+
+        $crate::impl_sortedmulti!(build_desc, sortedmulti $( $inner )*)
+    }};
+    ( $inner_struct:ident, $constructor:ident, $sortedmulti_constructor:ident, $ctx:ident, sortedmulti_vec $( $inner:tt )* ) => {{
+        use std::marker::PhantomData;
+
+        use $crate::miniscript::descriptor::{$inner_struct, Descriptor, DescriptorPublicKey};
+        use $crate::miniscript::$ctx;
+
+        let build_desc = |k, pks| {
+            Ok((Descriptor::<DescriptorPublicKey>::$inner_struct($inner_struct::$sortedmulti_constructor(k, pks)?), PhantomData::<$ctx>))
+        };
+
+        $crate::impl_sortedmulti!(build_desc, sortedmulti_vec $( $inner )*)
+    }};
+
+    ( $inner_struct:ident, $constructor:ident, $sortedmulti_constructor:ident, $ctx:ident, $( $minisc:tt )* ) => {{
+        use $crate::miniscript::descriptor::{$inner_struct, Descriptor, DescriptorPublicKey};
 
-    ( $descriptor_variant:ident, $sortedmulti_variant:ident, $( $minisc:tt )* ) => {
         $crate::fragment!($( $minisc )*)
-            .map(|(minisc, keymap, networks)|($crate::miniscript::Descriptor::<$crate::miniscript::descriptor::DescriptorPublicKey>::$descriptor_variant(minisc), keymap, networks))
-    };
+            .and_then(|(minisc, keymap, networks)| Ok(($inner_struct::$constructor(minisc)?, keymap, networks)))
+            .and_then(|(inner, key_map, valid_networks)| Ok((Descriptor::<DescriptorPublicKey>::$inner_struct(inner), key_map, valid_networks)))
+    }};
 }
 
 #[doc(hidden)]
 #[macro_export]
 macro_rules! impl_top_level_pk {
-    ( $descriptor_variant:ident, $ctx:ty, $key:expr ) => {{
+    ( $inner_type:ident, $ctx:ty, $key:expr ) => {{
+        use $crate::miniscript::descriptor::$inner_type;
+
         #[allow(unused_imports)]
-        use $crate::keys::{DescriptorKey, ToDescriptorKey};
+        use $crate::keys::{DescriptorKey, IntoDescriptorKey};
         let secp = $crate::bitcoin::secp256k1::Secp256k1::new();
 
-        $key.to_descriptor_key()
+        $key.into_descriptor_key()
             .and_then(|key: DescriptorKey<$ctx>| key.extract(&secp))
             .map_err($crate::descriptor::DescriptorError::Key)
-            .map(|(pk, key_map, valid_networks)| {
-                (
-                    $crate::miniscript::Descriptor::<
-                        $crate::miniscript::descriptor::DescriptorPublicKey,
-                    >::$descriptor_variant(pk),
-                    key_map,
-                    valid_networks,
-                )
-            })
+            .map(|(pk, key_map, valid_networks)| ($inner_type::new(pk), key_map, valid_networks))
     }};
 }
 
@@ -207,22 +220,22 @@ macro_rules! impl_node_opcode_three {
 #[doc(hidden)]
 #[macro_export]
 macro_rules! impl_sortedmulti {
-    ( sortedmulti_vec ( $thresh:expr, $keys:expr ) ) => ({
+    ( $build_desc:expr, sortedmulti_vec ( $thresh:expr, $keys:expr ) ) => ({
         let secp = $crate::bitcoin::secp256k1::Secp256k1::new();
-        $crate::keys::make_sortedmulti_inner($thresh, $keys, &secp)
+        $crate::keys::make_sortedmulti($thresh, $keys, $build_desc, &secp)
     });
-    ( sortedmulti ( $thresh:expr $(, $key:expr )+ ) ) => ({
-        use $crate::keys::ToDescriptorKey;
+    ( $build_desc:expr, sortedmulti ( $thresh:expr $(, $key:expr )+ ) ) => ({
+        use $crate::keys::IntoDescriptorKey;
         let secp = $crate::bitcoin::secp256k1::Secp256k1::new();
 
         let mut keys = vec![];
         $(
-            keys.push($key.to_descriptor_key());
+            keys.push($key.into_descriptor_key());
         )*
 
         keys.into_iter().collect::<Result<Vec<_>, _>>()
             .map_err($crate::descriptor::DescriptorError::Key)
-            .and_then(|keys| $crate::keys::make_sortedmulti_inner($thresh, keys, &secp))
+            .and_then(|keys| $crate::keys::make_sortedmulti($thresh, keys, $build_desc, &secp))
     });
 
 }
@@ -313,11 +326,11 @@ macro_rules! apply_modifier {
 /// broken up to `s:d:v:older(144)`.
 ///
 /// The `pk()`, `pk_k()` and `pk_h()` operands can take as argument any type that implements
-/// [`ToDescriptorKey`]. This means that keys can also be written inline as strings, but in that
+/// [`IntoDescriptorKey`]. This means that keys can also be written inline as strings, but in that
 /// case they must be wrapped in quotes, which is another difference compared to the standard
 /// descriptor syntax.
 ///
-/// [`ToDescriptorKey`]: crate::keys::ToDescriptorKey
+/// [`IntoDescriptorKey`]: crate::keys::IntoDescriptorKey
 ///
 /// ## Example
 ///
@@ -399,34 +412,46 @@ macro_rules! apply_modifier {
 #[macro_export]
 macro_rules! descriptor {
     ( bare ( $( $minisc:tt )* ) ) => ({
-        $crate::impl_top_level_sh!(Bare, Bare, $( $minisc )*)
+        $crate::impl_top_level_sh!(Bare, new, new, Legacy, $( $minisc )*)
     });
     ( sh ( wsh ( $( $minisc:tt )* ) ) ) => ({
         $crate::descriptor!(shwsh ($( $minisc )*))
     });
     ( shwsh ( $( $minisc:tt )* ) ) => ({
-        $crate::impl_top_level_sh!(ShWsh, ShWshSortedMulti, $( $minisc )*)
+        $crate::impl_top_level_sh!(Sh, new_wsh, new_wsh_sortedmulti, Segwitv0, $( $minisc )*)
     });
     ( pk ( $key:expr ) ) => ({
-        $crate::impl_top_level_pk!(Pk, $crate::miniscript::Legacy, $key)
+        // `pk()` is actually implemented as `bare(pk())`
+        $crate::descriptor!( bare ( pk ( $key ) ) )
     });
     ( pkh ( $key:expr ) ) => ({
-        $crate::impl_top_level_pk!(Pkh,$crate::miniscript::Legacy, $key)
+        use $crate::miniscript::descriptor::{Descriptor, DescriptorPublicKey};
+
+        $crate::impl_top_level_pk!(Pkh, $crate::miniscript::Legacy, $key)
+            .map(|(a, b, c)| (Descriptor::<DescriptorPublicKey>::Pkh(a), b, c))
     });
     ( wpkh ( $key:expr ) ) => ({
+        use $crate::miniscript::descriptor::{Descriptor, DescriptorPublicKey};
+
         $crate::impl_top_level_pk!(Wpkh, $crate::miniscript::Segwitv0, $key)
+            .and_then(|(a, b, c)| Ok((a?, b, c)))
+            .map(|(a, b, c)| (Descriptor::<DescriptorPublicKey>::Wpkh(a), b, c))
     });
     ( sh ( wpkh ( $key:expr ) ) ) => ({
         $crate::descriptor!(shwpkh ( $key ))
     });
     ( shwpkh ( $key:expr ) ) => ({
-        $crate::impl_top_level_pk!(ShWpkh, $crate::miniscript::Segwitv0, $key)
+        use $crate::miniscript::descriptor::{Descriptor, DescriptorPublicKey, Sh};
+
+        $crate::impl_top_level_pk!(Wpkh, $crate::miniscript::Segwitv0, $key)
+            .and_then(|(a, b, c)| Ok((a?, b, c)))
+            .and_then(|(a, b, c)| Ok((Descriptor::<DescriptorPublicKey>::Sh(Sh::new_wpkh(a.into_inner())?), b, c)))
     });
     ( sh ( $( $minisc:tt )* ) ) => ({
-        $crate::impl_top_level_sh!(Sh, ShSortedMulti, $( $minisc )*)
+        $crate::impl_top_level_sh!(Sh, new, new_sortedmulti, Legacy, $( $minisc )*)
     });
     ( wsh ( $( $minisc:tt )* ) ) => ({
-        $crate::impl_top_level_sh!(Wsh, WshSortedMulti, $( $minisc )*)
+        $crate::impl_top_level_sh!(Wsh, new, new_sortedmulti, Segwitv0, $( $minisc )*)
     });
 }
 
@@ -628,12 +653,12 @@ macro_rules! fragment {
         $crate::keys::make_multi($thresh, $keys)
     });
     ( multi ( $thresh:expr $(, $key:expr )+ ) ) => ({
-        use $crate::keys::ToDescriptorKey;
+        use $crate::keys::IntoDescriptorKey;
         let secp = $crate::bitcoin::secp256k1::Secp256k1::new();
 
         let mut keys = vec![];
         $(
-            keys.push($key.to_descriptor_key());
+            keys.push($key.into_descriptor_key());
         )*
 
         keys.into_iter().collect::<Result<Vec<_>, _>>()
@@ -654,18 +679,19 @@ macro_rules! fragment {
 mod test {
     use bitcoin::hashes::hex::ToHex;
     use bitcoin::secp256k1::Secp256k1;
-    use miniscript::descriptor::{DescriptorPublicKey, DescriptorPublicKeyCtx, KeyMap};
+    use miniscript::descriptor::{DescriptorPublicKey, DescriptorTrait, KeyMap};
     use miniscript::{Descriptor, Legacy, Segwitv0};
 
     use std::str::FromStr;
 
     use crate::descriptor::{DescriptorError, DescriptorMeta};
-    use crate::keys::{DescriptorKey, ToDescriptorKey, ValidNetworks};
-    use bitcoin::network::constants::Network::{Bitcoin, Regtest, Testnet};
+    use crate::keys::{DescriptorKey, IntoDescriptorKey, ValidNetworks};
+    use bitcoin::network::constants::Network::{Bitcoin, Regtest, Signet, Testnet};
     use bitcoin::util::bip32;
-    use bitcoin::util::bip32::ChildNumber;
     use bitcoin::PrivateKey;
 
+    use crate::descriptor::derived::AsDerived;
+
     // test the descriptor!() macro
 
     // verify descriptor generates expected script(s) (if bare or pk) or address(es)
@@ -676,30 +702,29 @@ mod test {
         expected: &[&str],
     ) {
         let secp = Secp256k1::new();
-        let deriv_ctx = DescriptorPublicKeyCtx::new(&secp, ChildNumber::Normal { index: 0 });
 
         let (desc, _key_map, _networks) = desc.unwrap();
         assert_eq!(desc.is_witness(), is_witness);
-        assert_eq!(desc.is_fixed(), is_fixed);
+        assert_eq!(!desc.is_deriveable(), is_fixed);
         for i in 0..expected.len() {
             let index = i as u32;
-            let child_desc = if desc.is_fixed() {
-                desc.clone()
+            let child_desc = if !desc.is_deriveable() {
+                desc.as_derived_fixed(&secp)
             } else {
-                desc.derive(ChildNumber::from_normal_idx(index).unwrap())
+                desc.as_derived(index, &secp)
             };
-            let address = child_desc.address(Regtest, deriv_ctx);
-            if let Some(address) = address {
+            let address = child_desc.address(Regtest);
+            if let Ok(address) = address {
                 assert_eq!(address.to_string(), *expected.get(i).unwrap());
             } else {
-                let script = child_desc.script_pubkey(deriv_ctx);
+                let script = child_desc.script_pubkey();
                 assert_eq!(script.to_hex().as_str(), *expected.get(i).unwrap());
             }
         }
     }
 
     // - at least one of each "type" of operator; ie. one modifier, one leaf_opcode, one leaf_opcode_value, etc.
-    // - mixing up key types that implement ToDescriptorKey in multi() or thresh()
+    // - mixing up key types that implement IntoDescriptorKey in multi() or thresh()
 
     // expected script for pk and bare manually created
     // expected addresses created with `bitcoin-cli getdescriptorinfo` (for hash) and `bitcoin-cli deriveaddresses`
@@ -783,7 +808,7 @@ mod test {
         let xprv = bip32::ExtendedPrivKey::from_str("tprv8ZgxMBicQKsPcx5nBGsR63Pe8KnRUqmbJNENAfGftF3yuXoMMoVJJcYeUw5eVkm9WBPjWYt6HMWYJNesB5HaNVBaFc1M6dRjWSYnmewUMYy").unwrap();
 
         let path = bip32::DerivationPath::from_str("m/0").unwrap();
-        let desc_key = (xprv, path.clone()).to_descriptor_key().unwrap();
+        let desc_key = (xprv, path.clone()).into_descriptor_key().unwrap();
         check(
             descriptor!(pk(desc_key)),
             false,
@@ -795,7 +820,7 @@ mod test {
             ],
         );
 
-        let desc_key = (xprv, path.clone()).to_descriptor_key().unwrap();
+        let desc_key = (xprv, path.clone()).into_descriptor_key().unwrap();
         check(
             descriptor!(pkh(desc_key)),
             false,
@@ -808,8 +833,8 @@ mod test {
         );
 
         let path2 = bip32::DerivationPath::from_str("m/2147483647'/0").unwrap();
-        let desc_key1 = (xprv, path).to_descriptor_key().unwrap();
-        let desc_key2 = (xprv, path2).to_descriptor_key().unwrap();
+        let desc_key1 = (xprv, path).into_descriptor_key().unwrap();
+        let desc_key2 = (xprv, path2).into_descriptor_key().unwrap();
 
         check(
             descriptor!(sh(multi(1, desc_key1, desc_key2))),
@@ -828,7 +853,7 @@ mod test {
         let xprv = bip32::ExtendedPrivKey::from_str("tprv8ZgxMBicQKsPcx5nBGsR63Pe8KnRUqmbJNENAfGftF3yuXoMMoVJJcYeUw5eVkm9WBPjWYt6HMWYJNesB5HaNVBaFc1M6dRjWSYnmewUMYy").unwrap();
 
         let path = bip32::DerivationPath::from_str("m/0").unwrap();
-        let desc_key = (xprv, path.clone()).to_descriptor_key().unwrap();
+        let desc_key = (xprv, path.clone()).into_descriptor_key().unwrap();
         check(
             descriptor!(wpkh(desc_key)),
             true,
@@ -840,7 +865,7 @@ mod test {
             ],
         );
 
-        let desc_key = (xprv, path.clone()).to_descriptor_key().unwrap();
+        let desc_key = (xprv, path.clone()).into_descriptor_key().unwrap();
         check(
             descriptor!(sh(wpkh(desc_key))),
             true,
@@ -853,8 +878,8 @@ mod test {
         );
 
         let path2 = bip32::DerivationPath::from_str("m/2147483647'/0").unwrap();
-        let desc_key1 = (xprv, path.clone()).to_descriptor_key().unwrap();
-        let desc_key2 = (xprv, path2.clone()).to_descriptor_key().unwrap();
+        let desc_key1 = (xprv, path.clone()).into_descriptor_key().unwrap();
+        let desc_key2 = (xprv, path2.clone()).into_descriptor_key().unwrap();
         check(
             descriptor!(wsh(multi(1, desc_key1, desc_key2))),
             true,
@@ -866,8 +891,8 @@ mod test {
             ],
         );
 
-        let desc_key1 = (xprv, path).to_descriptor_key().unwrap();
-        let desc_key2 = (xprv, path2).to_descriptor_key().unwrap();
+        let desc_key1 = (xprv, path).into_descriptor_key().unwrap();
+        let desc_key2 = (xprv, path2).into_descriptor_key().unwrap();
         check(
             descriptor!(sh(wsh(multi(1, desc_key1, desc_key2)))),
             true,
@@ -943,14 +968,17 @@ mod test {
     fn test_valid_networks() {
         let xprv = bip32::ExtendedPrivKey::from_str("tprv8ZgxMBicQKsPcx5nBGsR63Pe8KnRUqmbJNENAfGftF3yuXoMMoVJJcYeUw5eVkm9WBPjWYt6HMWYJNesB5HaNVBaFc1M6dRjWSYnmewUMYy").unwrap();
         let path = bip32::DerivationPath::from_str("m/0").unwrap();
-        let desc_key = (xprv, path.clone()).to_descriptor_key().unwrap();
+        let desc_key = (xprv, path.clone()).into_descriptor_key().unwrap();
 
         let (_desc, _key_map, valid_networks) = descriptor!(pkh(desc_key)).unwrap();
-        assert_eq!(valid_networks, [Testnet, Regtest].iter().cloned().collect());
+        assert_eq!(
+            valid_networks,
+            [Testnet, Regtest, Signet].iter().cloned().collect()
+        );
 
         let xprv = bip32::ExtendedPrivKey::from_str("xprv9s21ZrQH143K3QTDL4LXw2F7HEK3wJUD2nW2nRk4stbPy6cq3jPPqjiChkVvvNKmPGJxWUtg6LnF5kejMRNNU3TGtRBeJgk33yuGBxrMPHi").unwrap();
         let path = bip32::DerivationPath::from_str("m/10/20/30/40").unwrap();
-        let desc_key = (xprv, path.clone()).to_descriptor_key().unwrap();
+        let desc_key = (xprv, path.clone()).into_descriptor_key().unwrap();
 
         let (_desc, _key_map, valid_networks) = descriptor!(wpkh(desc_key)).unwrap();
         assert_eq!(valid_networks, [Bitcoin].iter().cloned().collect());
@@ -963,26 +991,26 @@ mod test {
 
         let xprv1 = bip32::ExtendedPrivKey::from_str("tprv8ZgxMBicQKsPcx5nBGsR63Pe8KnRUqmbJNENAfGftF3yuXoMMoVJJcYeUw5eVkm9WBPjWYt6HMWYJNesB5HaNVBaFc1M6dRjWSYnmewUMYy").unwrap();
         let path1 = bip32::DerivationPath::from_str("m/0").unwrap();
-        let desc_key1 = (xprv1, path1.clone()).to_descriptor_key().unwrap();
+        let desc_key1 = (xprv1, path1.clone()).into_descriptor_key().unwrap();
 
         let xprv2 = bip32::ExtendedPrivKey::from_str("tprv8ZgxMBicQKsPegBHHnq7YEgM815dG24M2Jk5RVqipgDxF1HJ1tsnT815X5Fd5FRfMVUs8NZs9XCb6y9an8hRPThnhfwfXJ36intaekySHGF").unwrap();
         let path2 = bip32::DerivationPath::from_str("m/2147483647'/0").unwrap();
-        let desc_key2 = (xprv2, path2.clone()).to_descriptor_key().unwrap();
+        let desc_key2 = (xprv2, path2.clone()).into_descriptor_key().unwrap();
 
         let xprv3 = bip32::ExtendedPrivKey::from_str("tprv8ZgxMBicQKsPdZXrcHNLf5JAJWFAoJ2TrstMRdSKtEggz6PddbuSkvHKM9oKJyFgZV1B7rw8oChspxyYbtmEXYyg1AjfWbL3ho3XHDpHRZf").unwrap();
         let path3 = bip32::DerivationPath::from_str("m/10/20/30/40").unwrap();
-        let desc_key3 = (xprv3, path3.clone()).to_descriptor_key().unwrap();
+        let desc_key3 = (xprv3, path3.clone()).into_descriptor_key().unwrap();
 
         let (_desc, key_map, _valid_networks) =
             descriptor!(sh(wsh(multi(2, desc_key1, desc_key2, desc_key3)))).unwrap();
         assert_eq!(key_map.len(), 3);
 
         let desc_key1: DescriptorKey<Segwitv0> =
-            (xprv1, path1.clone()).to_descriptor_key().unwrap();
+            (xprv1, path1.clone()).into_descriptor_key().unwrap();
         let desc_key2: DescriptorKey<Segwitv0> =
-            (xprv2, path2.clone()).to_descriptor_key().unwrap();
+            (xprv2, path2.clone()).into_descriptor_key().unwrap();
         let desc_key3: DescriptorKey<Segwitv0> =
-            (xprv3, path3.clone()).to_descriptor_key().unwrap();
+            (xprv3, path3.clone()).into_descriptor_key().unwrap();
 
         let (key1, _key_map, _valid_networks) = desc_key1.extract(&secp).unwrap();
         let (key2, _key_map, _valid_networks) = desc_key2.extract(&secp).unwrap();
@@ -992,19 +1020,19 @@ mod test {
         assert_eq!(key_map.get(&key3).unwrap().to_string(), "tprv8ZgxMBicQKsPdZXrcHNLf5JAJWFAoJ2TrstMRdSKtEggz6PddbuSkvHKM9oKJyFgZV1B7rw8oChspxyYbtmEXYyg1AjfWbL3ho3XHDpHRZf/10/20/30/40/*");
     }
 
-    // - verify the ScriptContext is correctly validated (i.e. passing a type that only impl ToDescriptorKey<Segwitv0> to a pkh() descriptor should throw a compilation error
+    // - verify the ScriptContext is correctly validated (i.e. passing a type that only impl IntoDescriptorKey<Segwitv0> to a pkh() descriptor should throw a compilation error
     #[test]
     fn test_script_context_validation() {
         // this compiles
         let xprv = bip32::ExtendedPrivKey::from_str("tprv8ZgxMBicQKsPcx5nBGsR63Pe8KnRUqmbJNENAfGftF3yuXoMMoVJJcYeUw5eVkm9WBPjWYt6HMWYJNesB5HaNVBaFc1M6dRjWSYnmewUMYy").unwrap();
         let path = bip32::DerivationPath::from_str("m/0").unwrap();
-        let desc_key: DescriptorKey<Legacy> = (xprv, path.clone()).to_descriptor_key().unwrap();
+        let desc_key: DescriptorKey<Legacy> = (xprv, path.clone()).into_descriptor_key().unwrap();
 
         let (desc, _key_map, _valid_networks) = descriptor!(pkh(desc_key)).unwrap();
-        assert_eq!(desc.to_string(), "pkh(tpubD6NzVbkrYhZ4WR7a4vY1VT3khMJMeAxVsfq9TBJyJWrNk247zCJtV7AWf6UJP7rAVsn8NNKdJi3gFyKPTmWZS9iukb91xbn2HbFSMQm2igY/0/*)");
+        assert_eq!(desc.to_string(), "pkh(tpubD6NzVbkrYhZ4WR7a4vY1VT3khMJMeAxVsfq9TBJyJWrNk247zCJtV7AWf6UJP7rAVsn8NNKdJi3gFyKPTmWZS9iukb91xbn2HbFSMQm2igY/0/*)#yrnz9pp2");
 
         // as expected this does not compile due to invalid context
-        //let desc_key:DescriptorKey<Segwitv0> = (xprv, path.clone()).to_descriptor_key().unwrap();
+        //let desc_key:DescriptorKey<Segwitv0> = (xprv, path.clone()).into_descriptor_key().unwrap();
         //let (desc, _key_map, _valid_networks) = descriptor!(pkh(desc_key)).unwrap();
     }
 
@@ -1015,17 +1043,16 @@ mod test {
         let (descriptor, _, _) =
             descriptor!(wsh(thresh(2,d:v:older(1),s:pk(private_key),s:pk(private_key)))).unwrap();
 
-        assert_eq!(descriptor.to_string(), "wsh(thresh(2,dv:older(1),s:pk(02e96fe52ef0e22d2f131dd425ce1893073a3c6ad20e8cac36726393dfb4856a4c),s:pk(02e96fe52ef0e22d2f131dd425ce1893073a3c6ad20e8cac36726393dfb4856a4c)))")
+        assert_eq!(descriptor.to_string(), "wsh(thresh(2,dv:older(1),s:pk(02e96fe52ef0e22d2f131dd425ce1893073a3c6ad20e8cac36726393dfb4856a4c),s:pk(02e96fe52ef0e22d2f131dd425ce1893073a3c6ad20e8cac36726393dfb4856a4c)))#cfdcqs3s")
     }
 
-    // TODO: uncomment once https://github.com/rust-bitcoin/rust-miniscript/pull/221 is released
-    //
-    // #[test]
-    // #[should_panic(expected = "Miniscript(ContextError(CompressedOnly))")]
-    // fn test_dsl_miniscript_checks() {
-    //     let mut uncompressed_pk = PrivateKey::from_wif("L5EZftvrYaSudiozVRzTqLcHLNDoVn7H5HSfM9BAN6tMJX8oTWz6").unwrap();
-    //     uncompressed_pk.compressed = false;
+    #[test]
+    #[should_panic(expected = "Miniscript(ContextError(CompressedOnly))")]
+    fn test_dsl_miniscript_checks() {
+        let mut uncompressed_pk =
+            PrivateKey::from_wif("L5EZftvrYaSudiozVRzTqLcHLNDoVn7H5HSfM9BAN6tMJX8oTWz6").unwrap();
+        uncompressed_pk.compressed = false;
 
-    //     descriptor!(wsh(v:pk(uncompressed_pk))).unwrap();
-    // }
+        descriptor!(wsh(v: pk(uncompressed_pk))).unwrap();
+    }
 }

src/descriptor/error.rs

@@ -31,6 +31,8 @@ pub enum Error {
     InvalidHDKeyPath,
     /// The provided descriptor doesn't match its checksum
     InvalidDescriptorChecksum,
+    /// The descriptor contains hardened derivation steps on public extended keys
+    HardenedDerivationXpub,
 
     /// Error thrown while working with [`keys`](crate::keys)
     Key(crate::keys::KeyError),

src/descriptor/mod.rs

@@ -28,20 +28,20 @@
 //! from [`miniscript`].
 
 use std::collections::{BTreeMap, HashMap};
-use std::fmt;
+use std::ops::Deref;
 
-use bitcoin::secp256k1::Secp256k1;
-use bitcoin::util::bip32::{ChildNumber, DerivationPath, ExtendedPubKey, Fingerprint, KeySource};
+use bitcoin::util::bip32::{
+    ChildNumber, DerivationPath, ExtendedPrivKey, ExtendedPubKey, Fingerprint, KeySource,
+};
 use bitcoin::util::psbt;
 use bitcoin::{Network, PublicKey, Script, TxOut};
 
-use miniscript::descriptor::{DescriptorPublicKey, DescriptorXKey, InnerXKey};
-pub use miniscript::{
-    descriptor::KeyMap, Descriptor, Legacy, Miniscript, MiniscriptKey, ScriptContext, Segwitv0,
-    Terminal, ToPublicKey,
-};
+use miniscript::descriptor::{DescriptorPublicKey, DescriptorType, DescriptorXKey, Wildcard};
+pub use miniscript::{descriptor::KeyMap, Descriptor, Legacy, Miniscript, ScriptContext, Segwitv0};
+use miniscript::{DescriptorTrait, ForEachKey, TranslatePk};
 
 pub mod checksum;
+pub(crate) mod derived;
 #[doc(hidden)]
 pub mod dsl;
 pub mod error;
@@ -49,16 +49,21 @@ pub mod policy;
 pub mod template;
 
 pub use self::checksum::get_checksum;
+use self::derived::AsDerived;
+pub use self::derived::DerivedDescriptorKey;
 pub use self::error::Error as DescriptorError;
 pub use self::policy::Policy;
 use self::template::DescriptorTemplateOut;
-use crate::keys::{KeyError, ToDescriptorKey};
+use crate::keys::{IntoDescriptorKey, KeyError};
 use crate::wallet::signer::SignersContainer;
-use crate::wallet::utils::{descriptor_to_pk_ctx, SecpCtx};
+use crate::wallet::utils::SecpCtx;
 
 /// Alias for a [`Descriptor`] that can contain extended keys using [`DescriptorPublicKey`]
 pub type ExtendedDescriptor = Descriptor<DescriptorPublicKey>;
 
+/// Alias for a [`Descriptor`] that contains extended **derived** keys
+pub type DerivedDescriptor<'s> = Descriptor<DerivedDescriptorKey<'s>>;
+
 /// Alias for the type of maps that represent derivation paths in a [`psbt::Input`] or
 /// [`psbt::Output`]
 ///
@@ -67,17 +72,19 @@ pub type ExtendedDescriptor = Descriptor<DescriptorPublicKey>;
 pub type HDKeyPaths = BTreeMap<PublicKey, KeySource>;
 
 /// Trait for types which can be converted into an [`ExtendedDescriptor`] and a [`KeyMap`] usable by a wallet in a specific [`Network`]
-pub trait ToWalletDescriptor {
+pub trait IntoWalletDescriptor {
     /// Convert to wallet descriptor
-    fn to_wallet_descriptor(
+    fn into_wallet_descriptor(
         self,
+        secp: &SecpCtx,
         network: Network,
     ) -> Result<(ExtendedDescriptor, KeyMap), DescriptorError>;
 }
 
-impl ToWalletDescriptor for &str {
-    fn to_wallet_descriptor(
+impl IntoWalletDescriptor for &str {
+    fn into_wallet_descriptor(
         self,
+        secp: &SecpCtx,
         network: Network,
     ) -> Result<(ExtendedDescriptor, KeyMap), DescriptorError> {
         let descriptor = if self.contains('#') {
@@ -95,45 +102,47 @@ impl ToWalletDescriptor for &str {
             self
         };
 
-        ExtendedDescriptor::parse_descriptor(descriptor)?.to_wallet_descriptor(network)
+        ExtendedDescriptor::parse_descriptor(secp, descriptor)?
+            .into_wallet_descriptor(secp, network)
     }
 }
 
-impl ToWalletDescriptor for &String {
-    fn to_wallet_descriptor(
+impl IntoWalletDescriptor for &String {
+    fn into_wallet_descriptor(
         self,
+        secp: &SecpCtx,
         network: Network,
     ) -> Result<(ExtendedDescriptor, KeyMap), DescriptorError> {
-        self.as_str().to_wallet_descriptor(network)
+        self.as_str().into_wallet_descriptor(secp, network)
     }
 }
 
-impl ToWalletDescriptor for ExtendedDescriptor {
-    fn to_wallet_descriptor(
+impl IntoWalletDescriptor for ExtendedDescriptor {
+    fn into_wallet_descriptor(
         self,
+        secp: &SecpCtx,
         network: Network,
     ) -> Result<(ExtendedDescriptor, KeyMap), DescriptorError> {
-        (self, KeyMap::default()).to_wallet_descriptor(network)
+        (self, KeyMap::default()).into_wallet_descriptor(secp, network)
     }
 }
 
-impl ToWalletDescriptor for (ExtendedDescriptor, KeyMap) {
-    fn to_wallet_descriptor(
+impl IntoWalletDescriptor for (ExtendedDescriptor, KeyMap) {
+    fn into_wallet_descriptor(
         self,
+        secp: &SecpCtx,
         network: Network,
     ) -> Result<(ExtendedDescriptor, KeyMap), DescriptorError> {
         use crate::keys::DescriptorKey;
 
-        let secp = Secp256k1::new();
-
         let check_key = |pk: &DescriptorPublicKey| {
             let (pk, _, networks) = if self.0.is_witness() {
                 let desciptor_key: DescriptorKey<miniscript::Segwitv0> =
-                    pk.clone().to_descriptor_key()?;
+                    pk.clone().into_descriptor_key()?;
                 desciptor_key.extract(&secp)?
             } else {
                 let desciptor_key: DescriptorKey<miniscript::Legacy> =
-                    pk.clone().to_descriptor_key()?;
+                    pk.clone().into_descriptor_key()?;
                 desciptor_key.extract(&secp)?
             };
 
@@ -151,9 +160,10 @@ impl ToWalletDescriptor for (ExtendedDescriptor, KeyMap) {
     }
 }
 
-impl ToWalletDescriptor for DescriptorTemplateOut {
-    fn to_wallet_descriptor(
+impl IntoWalletDescriptor for DescriptorTemplateOut {
+    fn into_wallet_descriptor(
         self,
+        _secp: &SecpCtx,
         network: Network,
     ) -> Result<(ExtendedDescriptor, KeyMap), DescriptorError> {
         let valid_networks = &self.2;
@@ -188,6 +198,36 @@ impl ToWalletDescriptor for DescriptorTemplateOut {
     }
 }
 
+/// Wrapper for `IntoWalletDescriptor` that performs additional checks on the keys contained in the
+/// descriptor
+pub(crate) fn into_wallet_descriptor_checked<T: IntoWalletDescriptor>(
+    inner: T,
+    secp: &SecpCtx,
+    network: Network,
+) -> Result<(ExtendedDescriptor, KeyMap), DescriptorError> {
+    let (descriptor, keymap) = inner.into_wallet_descriptor(secp, network)?;
+
+    // Ensure the keys don't contain any hardened derivation steps or hardened wildcards
+    let descriptor_contains_hardened_steps = descriptor.for_any_key(|k| {
+        if let DescriptorPublicKey::XPub(DescriptorXKey {
+            derivation_path,
+            wildcard,
+            ..
+        }) = k.as_key()
+        {
+            return *wildcard == Wildcard::Hardened
+                || derivation_path.into_iter().any(ChildNumber::is_hardened);
+        }
+
+        false
+    });
+    if descriptor_contains_hardened_steps {
+        return Err(DescriptorError::HardenedDerivationXpub);
+    }
+
+    Ok((descriptor, keymap))
+}
+
 #[doc(hidden)]
 /// Used internally mainly by the `descriptor!()` and `fragment!()` macros
 pub trait CheckMiniscript<Ctx: miniscript::ScriptContext> {
@@ -219,7 +259,12 @@ pub(crate) trait XKeyUtils {
     fn root_fingerprint(&self, secp: &SecpCtx) -> Fingerprint;
 }
 
-impl<K: InnerXKey> XKeyUtils for DescriptorXKey<K> {
+// FIXME: `InnerXKey` was made private in rust-miniscript, so we have to implement this manually on
+// both `ExtendedPubKey` and `ExtendedPrivKey`.
+//
+// Revert back to using the trait once https://github.com/rust-bitcoin/rust-miniscript/pull/230 is
+// released
+impl XKeyUtils for DescriptorXKey<ExtendedPubKey> {
     fn full_path(&self, append: &[ChildNumber]) -> DerivationPath {
         let full_path = match self.origin {
             Some((_, ref path)) => path
@@ -230,7 +275,36 @@ impl<K: InnerXKey> XKeyUtils for DescriptorXKey<K> {
             None => self.derivation_path.clone(),
         };
 
-        if self.is_wildcard {
+        if self.wildcard != Wildcard::None {
+            full_path
+                .into_iter()
+                .chain(append.iter())
+                .cloned()
+                .collect()
+        } else {
+            full_path
+        }
+    }
+
+    fn root_fingerprint(&self, _: &SecpCtx) -> Fingerprint {
+        match self.origin {
+            Some((fingerprint, _)) => fingerprint,
+            None => self.xkey.fingerprint(),
+        }
+    }
+}
+impl XKeyUtils for DescriptorXKey<ExtendedPrivKey> {
+    fn full_path(&self, append: &[ChildNumber]) -> DerivationPath {
+        let full_path = match self.origin {
+            Some((_, ref path)) => path
+                .into_iter()
+                .chain(self.derivation_path.into_iter())
+                .cloned()
+                .collect(),
+            None => self.derivation_path.clone(),
+        };
+
+        if self.wildcard != Wildcard::None {
             full_path
                 .into_iter()
                 .chain(append.iter())
@@ -244,195 +318,111 @@ impl<K: InnerXKey> XKeyUtils for DescriptorXKey<K> {
     fn root_fingerprint(&self, secp: &SecpCtx) -> Fingerprint {
         match self.origin {
             Some((fingerprint, _)) => fingerprint,
-            None => self.xkey.xkey_fingerprint(secp),
+            None => self.xkey.fingerprint(secp),
         }
     }
 }
 
-pub(crate) trait DescriptorMeta: Sized {
+pub(crate) trait DerivedDescriptorMeta {
+    fn get_hd_keypaths(&self, secp: &SecpCtx) -> Result<HDKeyPaths, DescriptorError>;
+}
+
+pub(crate) trait DescriptorMeta {
     fn is_witness(&self) -> bool;
-    fn get_hd_keypaths(&self, index: u32, secp: &SecpCtx) -> Result<HDKeyPaths, DescriptorError>;
     fn get_extended_keys(&self) -> Result<Vec<DescriptorXKey<ExtendedPubKey>>, DescriptorError>;
-    fn is_fixed(&self) -> bool;
-    fn derive_from_hd_keypaths(&self, hd_keypaths: &HDKeyPaths, secp: &SecpCtx) -> Option<Self>;
-    fn derive_from_psbt_input(
+    fn derive_from_hd_keypaths<'s>(
+        &self,
+        hd_keypaths: &HDKeyPaths,
+        secp: &'s SecpCtx,
+    ) -> Option<DerivedDescriptor<'s>>;
+    fn derive_from_psbt_input<'s>(
         &self,
         psbt_input: &psbt::Input,
         utxo: Option<TxOut>,
-        secp: &SecpCtx,
-    ) -> Option<Self>;
+        secp: &'s SecpCtx,
+    ) -> Option<DerivedDescriptor<'s>>;
 }
 
 pub(crate) trait DescriptorScripts {
-    fn psbt_redeem_script(&self, secp: &SecpCtx) -> Option<Script>;
-    fn psbt_witness_script(&self, secp: &SecpCtx) -> Option<Script>;
+    fn psbt_redeem_script(&self) -> Option<Script>;
+    fn psbt_witness_script(&self) -> Option<Script>;
 }
 
-impl DescriptorScripts for Descriptor<DescriptorPublicKey> {
-    fn psbt_redeem_script(&self, secp: &SecpCtx) -> Option<Script> {
-        let deriv_ctx = descriptor_to_pk_ctx(secp);
-
-        match self {
-            Descriptor::ShWpkh(_) => Some(self.witness_script(deriv_ctx)),
-            Descriptor::ShWsh(ref script) => Some(script.encode(deriv_ctx).to_v0_p2wsh()),
-            Descriptor::Sh(ref script) => Some(script.encode(deriv_ctx)),
-            Descriptor::Bare(ref script) => Some(script.encode(deriv_ctx)),
-            Descriptor::ShSortedMulti(ref keys) => Some(keys.encode(deriv_ctx)),
+impl<'s> DescriptorScripts for DerivedDescriptor<'s> {
+    fn psbt_redeem_script(&self) -> Option<Script> {
+        match self.desc_type() {
+            DescriptorType::ShWpkh => Some(self.explicit_script()),
+            DescriptorType::ShWsh => Some(self.explicit_script().to_v0_p2wsh()),
+            DescriptorType::Sh => Some(self.explicit_script()),
+            DescriptorType::Bare => Some(self.explicit_script()),
+            DescriptorType::ShSortedMulti => Some(self.explicit_script()),
             _ => None,
         }
     }
 
-    fn psbt_witness_script(&self, secp: &SecpCtx) -> Option<Script> {
-        let deriv_ctx = descriptor_to_pk_ctx(secp);
-
-        match self {
-            Descriptor::Wsh(ref script) => Some(script.encode(deriv_ctx)),
-            Descriptor::ShWsh(ref script) => Some(script.encode(deriv_ctx)),
-            Descriptor::WshSortedMulti(ref keys) | Descriptor::ShWshSortedMulti(ref keys) => {
-                Some(keys.encode(deriv_ctx))
+    fn psbt_witness_script(&self) -> Option<Script> {
+        match self.desc_type() {
+            DescriptorType::Wsh => Some(self.explicit_script()),
+            DescriptorType::ShWsh => Some(self.explicit_script()),
+            DescriptorType::WshSortedMulti | DescriptorType::ShWshSortedMulti => {
+                Some(self.explicit_script())
             }
             _ => None,
         }
     }
 }
 
-impl DescriptorMeta for Descriptor<DescriptorPublicKey> {
+impl DescriptorMeta for ExtendedDescriptor {
     fn is_witness(&self) -> bool {
-        match self {
-            Descriptor::Bare(_)
-            | Descriptor::Pk(_)
-            | Descriptor::Pkh(_)
-            | Descriptor::Sh(_)
-            | Descriptor::ShSortedMulti(_) => false,
-            Descriptor::Wpkh(_)
-            | Descriptor::ShWpkh(_)
-            | Descriptor::Wsh(_)
-            | Descriptor::ShWsh(_)
-            | Descriptor::ShWshSortedMulti(_)
-            | Descriptor::WshSortedMulti(_) => true,
-        }
-    }
-
-    fn get_hd_keypaths(&self, index: u32, secp: &SecpCtx) -> Result<HDKeyPaths, DescriptorError> {
-        let translate_key = |key: &DescriptorPublicKey,
-                             index: u32,
-                             paths: &mut HDKeyPaths|
-         -> Result<DummyKey, DescriptorError> {
-            match key {
-                DescriptorPublicKey::SinglePub(_) => {}
-                DescriptorPublicKey::XPub(xpub) => {
-                    let derive_path = if xpub.is_wildcard {
-                        xpub.derivation_path
-                            .into_iter()
-                            .chain([ChildNumber::from_normal_idx(index)?].iter())
-                            .cloned()
-                            .collect()
-                    } else {
-                        xpub.derivation_path.clone()
-                    };
-                    let derived_pubkey = xpub
-                        .xkey
-                        .derive_pub(&Secp256k1::verification_only(), &derive_path)?;
-
-                    paths.insert(
-                        derived_pubkey.public_key,
-                        (
-                            xpub.root_fingerprint(secp),
-                            xpub.full_path(&[ChildNumber::from_normal_idx(index)?]),
-                        ),
-                    );
-                }
-            }
-
-            Ok(DummyKey::default())
-        };
-
-        let mut answer_pk = BTreeMap::new();
-        let mut answer_pkh = BTreeMap::new();
-
-        self.translate_pk(
-            |pk| translate_key(pk, index, &mut answer_pk),
-            |pkh| translate_key(pkh, index, &mut answer_pkh),
-        )?;
-
-        answer_pk.append(&mut answer_pkh);
-
-        Ok(answer_pk)
+        matches!(
+            self.desc_type(),
+            DescriptorType::Wpkh
+                | DescriptorType::ShWpkh
+                | DescriptorType::Wsh
+                | DescriptorType::ShWsh
+                | DescriptorType::ShWshSortedMulti
+                | DescriptorType::WshSortedMulti
+        )
     }
 
     fn get_extended_keys(&self) -> Result<Vec<DescriptorXKey<ExtendedPubKey>>, DescriptorError> {
-        let get_key = |key: &DescriptorPublicKey,
-                       keys: &mut Vec<DescriptorXKey<ExtendedPubKey>>|
-         -> Result<DummyKey, DescriptorError> {
-            if let DescriptorPublicKey::XPub(xpub) = key {
-                keys.push(xpub.clone())
+        let mut answer = Vec::new();
+
+        self.for_each_key(|pk| {
+            if let DescriptorPublicKey::XPub(xpub) = pk.as_key() {
+                answer.push(xpub.clone());
             }
 
-            Ok(DummyKey::default())
-        };
+            true
+        });
 
-        let mut answer_pk = Vec::new();
-        let mut answer_pkh = Vec::new();
-
-        self.translate_pk(
-            |pk| get_key(pk, &mut answer_pk),
-            |pkh| get_key(pkh, &mut answer_pkh),
-        )?;
-
-        answer_pk.append(&mut answer_pkh);
-
-        Ok(answer_pk)
+        Ok(answer)
     }
 
-    fn is_fixed(&self) -> bool {
-        fn check_key(
-            key: &DescriptorPublicKey,
-            flag: &mut bool,
-        ) -> Result<DummyKey, DescriptorError> {
-            match key {
-                DescriptorPublicKey::SinglePub(_) => {}
-                DescriptorPublicKey::XPub(xpub) => {
-                    if xpub.is_wildcard {
-                        *flag = true;
-                    }
-                }
-            }
+    fn derive_from_hd_keypaths<'s>(
+        &self,
+        hd_keypaths: &HDKeyPaths,
+        secp: &'s SecpCtx,
+    ) -> Option<DerivedDescriptor<'s>> {
+        let index: HashMap<_, _> = hd_keypaths.values().map(|(a, b)| (a, b)).collect();
 
-            Ok(DummyKey::default())
-        }
-
-        let mut found_wildcard_pk = false;
-        let mut found_wildcard_pkh = false;
-
-        self.translate_pk(
-            |pk| check_key(pk, &mut found_wildcard_pk),
-            |pkh| check_key(pkh, &mut found_wildcard_pkh),
-        )
-        .unwrap();
-
-        !found_wildcard_pk && !found_wildcard_pkh
-    }
-
-    fn derive_from_hd_keypaths(&self, hd_keypaths: &HDKeyPaths, secp: &SecpCtx) -> Option<Self> {
-        let try_key = |key: &DescriptorPublicKey,
-                       index: &HashMap<Fingerprint, DerivationPath>,
-                       found_path: &mut Option<ChildNumber>|
-         -> Result<DummyKey, DescriptorError> {
-            if found_path.is_some() {
+        let mut path_found = None;
+        self.for_each_key(|key| {
+            if path_found.is_some() {
                 // already found a matching path, we are done
-                return Ok(DummyKey::default());
+                return true;
             }
 
-            if let DescriptorPublicKey::XPub(xpub) = key {
+            if let DescriptorPublicKey::XPub(xpub) = key.as_key().deref() {
                 // Check if the key matches one entry in our `index`. If it does, `matches()` will
                 // return the "prefix" that matched, so we remove that prefix from the full path
                 // found in `index` and save it in `derive_path`. We expect this to be a derivation
-                // path of length 1 if the key `is_wildcard` and an empty path otherwise.
+                // path of length 1 if the key is `wildcard` and an empty path otherwise.
                 let root_fingerprint = xpub.root_fingerprint(secp);
                 let derivation_path: Option<Vec<ChildNumber>> = index
                     .get_key_value(&root_fingerprint)
                     .and_then(|(fingerprint, path)| {
-                        xpub.matches(&(*fingerprint, path.clone()), secp)
+                        xpub.matches(&(**fingerprint, (*path).clone()), secp)
                     })
                     .map(|prefix| {
                         index
@@ -445,128 +435,90 @@ impl DescriptorMeta for Descriptor<DescriptorPublicKey> {
                     });
 
                 match derivation_path {
-                    Some(path) if xpub.is_wildcard && path.len() == 1 => {
-                        *found_path = Some(path[0])
+                    Some(path) if xpub.wildcard != Wildcard::None && path.len() == 1 => {
+                        // Ignore hardened wildcards
+                        if let ChildNumber::Normal { index } = path[0] {
+                            path_found = Some(index)
+                        }
                     }
-                    Some(path) if !xpub.is_wildcard && path.is_empty() => {
-                        *found_path = Some(ChildNumber::Normal { index: 0 })
+                    Some(path) if xpub.wildcard == Wildcard::None && path.is_empty() => {
+                        path_found = Some(0)
                     }
-                    Some(_) => return Err(DescriptorError::InvalidHDKeyPath),
                     _ => {}
                 }
             }
 
-            Ok(DummyKey::default())
-        };
+            true
+        });
 
-        let index: HashMap<_, _> = hd_keypaths.values().cloned().collect();
-
-        let mut found_path_pk = None;
-        let mut found_path_pkh = None;
-
-        if self
-            .translate_pk(
-                |pk| try_key(pk, &index, &mut found_path_pk),
-                |pkh| try_key(pkh, &index, &mut found_path_pkh),
-            )
-            .is_err()
-        {
-            return None;
-        }
-
-        // if we have found a path for both `found_path_pk` and `found_path_pkh` but they are
-        // different we consider this an error and return None. we only return a path either if
-        // they are equal or if only one of them is Some(_)
-        let merged_path = match (found_path_pk, found_path_pkh) {
-            (Some(a), Some(b)) if a != b => return None,
-            (a, b) => a.or(b),
-        };
-
-        merged_path.map(|path| self.derive(path))
+        path_found.map(|path| self.as_derived(path, secp))
     }
 
-    fn derive_from_psbt_input(
+    fn derive_from_psbt_input<'s>(
         &self,
         psbt_input: &psbt::Input,
         utxo: Option<TxOut>,
-        secp: &SecpCtx,
-    ) -> Option<Self> {
-        if let Some(derived) = self.derive_from_hd_keypaths(&psbt_input.hd_keypaths, secp) {
+        secp: &'s SecpCtx,
+    ) -> Option<DerivedDescriptor<'s>> {
+        if let Some(derived) = self.derive_from_hd_keypaths(&psbt_input.bip32_derivation, secp) {
             return Some(derived);
-        } else if !self.is_fixed() {
-            // If the descriptor is not fixed we can't brute-force the derivation address, so just
-            // exit here
+        }
+        if self.is_deriveable() {
+            // We can't try to bruteforce the derivation index, exit here
             return None;
         }
 
-        let deriv_ctx = descriptor_to_pk_ctx(secp);
-        match self {
-            Descriptor::Pk(_)
-            | Descriptor::Pkh(_)
-            | Descriptor::Wpkh(_)
-            | Descriptor::ShWpkh(_)
+        let descriptor = self.as_derived_fixed(secp);
+        match descriptor.desc_type() {
+            // TODO: add pk() here
+            DescriptorType::Pkh | DescriptorType::Wpkh | DescriptorType::ShWpkh
                 if utxo.is_some()
-                    && self.script_pubkey(deriv_ctx) == utxo.as_ref().unwrap().script_pubkey =>
+                    && descriptor.script_pubkey() == utxo.as_ref().unwrap().script_pubkey =>
             {
-                Some(self.clone())
+                Some(descriptor)
             }
-            Descriptor::Bare(ms)
+            DescriptorType::Bare | DescriptorType::Sh | DescriptorType::ShSortedMulti
                 if psbt_input.redeem_script.is_some()
-                    && &ms.encode(deriv_ctx) == psbt_input.redeem_script.as_ref().unwrap() =>
+                    && &descriptor.explicit_script()
+                        == psbt_input.redeem_script.as_ref().unwrap() =>
             {
-                Some(self.clone())
+                Some(descriptor)
             }
-            Descriptor::Sh(ms)
-                if psbt_input.redeem_script.is_some()
-                    && &ms.encode(deriv_ctx) == psbt_input.redeem_script.as_ref().unwrap() =>
-            {
-                Some(self.clone())
-            }
-            Descriptor::Wsh(ms) | Descriptor::ShWsh(ms)
+            DescriptorType::Wsh
+            | DescriptorType::ShWsh
+            | DescriptorType::ShWshSortedMulti
+            | DescriptorType::WshSortedMulti
                 if psbt_input.witness_script.is_some()
-                    && &ms.encode(deriv_ctx) == psbt_input.witness_script.as_ref().unwrap() =>
+                    && &descriptor.explicit_script()
+                        == psbt_input.witness_script.as_ref().unwrap() =>
             {
-                Some(self.clone())
-            }
-            Descriptor::ShSortedMulti(keys)
-                if psbt_input.redeem_script.is_some()
-                    && &keys.encode(deriv_ctx) == psbt_input.redeem_script.as_ref().unwrap() =>
-            {
-                Some(self.clone())
-            }
-            Descriptor::WshSortedMulti(keys) | Descriptor::ShWshSortedMulti(keys)
-                if psbt_input.witness_script.is_some()
-                    && &keys.encode(deriv_ctx) == psbt_input.witness_script.as_ref().unwrap() =>
-            {
-                Some(self.clone())
+                Some(descriptor)
             }
             _ => None,
         }
     }
 }
 
-#[derive(Debug, Clone, Hash, PartialEq, PartialOrd, Eq, Ord, Default)]
-struct DummyKey();
+impl<'s> DerivedDescriptorMeta for DerivedDescriptor<'s> {
+    fn get_hd_keypaths(&self, secp: &SecpCtx) -> Result<HDKeyPaths, DescriptorError> {
+        let mut answer = BTreeMap::new();
+        self.for_each_key(|key| {
+            if let DescriptorPublicKey::XPub(xpub) = key.as_key().deref() {
+                let derived_pubkey = xpub
+                    .xkey
+                    .derive_pub(secp, &xpub.derivation_path)
+                    .expect("Derivation can't fail");
 
-impl fmt::Display for DummyKey {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "DummyKey")
-    }
-}
+                answer.insert(
+                    derived_pubkey.public_key,
+                    (xpub.root_fingerprint(secp), xpub.full_path(&[])),
+                );
+            }
 
-impl std::str::FromStr for DummyKey {
-    type Err = ();
+            true
+        });
 
-    fn from_str(_: &str) -> Result<Self, Self::Err> {
-        Ok(DummyKey::default())
-    }
-}
-
-impl miniscript::MiniscriptKey for DummyKey {
-    type Hash = DummyKey;
-
-    fn to_pubkeyhash(&self) -> DummyKey {
-        DummyKey::default()
+        Ok(answer)
     }
 }
 
@@ -692,118 +644,144 @@ mod test {
 
     #[test]
     fn test_to_wallet_descriptor_fixup_networks() {
-        use crate::keys::{any_network, ToDescriptorKey};
+        use crate::keys::{any_network, IntoDescriptorKey};
+
+        let secp = Secp256k1::new();
 
         let xpub = bip32::ExtendedPubKey::from_str("xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL").unwrap();
         let path = bip32::DerivationPath::from_str("m/0").unwrap();
 
         // here `to_descriptor_key` will set the valid networks for the key to only mainnet, since
         // we are using an "xpub"
-        let key = (xpub, path).to_descriptor_key().unwrap();
+        let key = (xpub, path).into_descriptor_key().unwrap();
         // override it with any. this happens in some key conversions, like bip39
         let key = key.override_valid_networks(any_network());
 
         // make a descriptor out of it
         let desc = crate::descriptor!(wpkh(key)).unwrap();
         // this should conver the key that supports "any_network" to the right network (testnet)
-        let (wallet_desc, _) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
+        let (wallet_desc, _) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
 
-        assert_eq!(wallet_desc.to_string(), "wpkh(tpubDEnoLuPdBep9bzw5LoGYpsxUQYheRQ9gcgrJhJEcdKFB9cWQRyYmkCyRoTqeD4tJYiVVgt6A3rN6rWn9RYhR9sBsGxji29LYWHuKKbdb1ev/0/*)");
+        assert_eq!(wallet_desc.to_string(), "wpkh(tpubDEnoLuPdBep9bzw5LoGYpsxUQYheRQ9gcgrJhJEcdKFB9cWQRyYmkCyRoTqeD4tJYiVVgt6A3rN6rWn9RYhR9sBsGxji29LYWHuKKbdb1ev/0/*)#y8p7e8kk");
     }
 
-    // test ToWalletDescriptor trait from &str with and without checksum appended
+    // test IntoWalletDescriptor trait from &str with and without checksum appended
     #[test]
     fn test_descriptor_from_str_with_checksum() {
+        let secp = Secp256k1::new();
+
         let desc = "wpkh(tprv8ZgxMBicQKsPdpkqS7Eair4YxjcuuvDPNYmKX3sCniCf16tHEVrjjiSXEkFRnUH77yXc6ZcwHHcLNfjdi5qUvw3VDfgYiH5mNsj5izuiu2N/1/2/*)#tqz0nc62"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(desc.is_ok());
 
         let desc = "wpkh(tprv8ZgxMBicQKsPdpkqS7Eair4YxjcuuvDPNYmKX3sCniCf16tHEVrjjiSXEkFRnUH77yXc6ZcwHHcLNfjdi5qUvw3VDfgYiH5mNsj5izuiu2N/1/2/*)"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(desc.is_ok());
 
         let desc = "wpkh(tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK/1/2/*)#67ju93jw"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(desc.is_ok());
 
         let desc = "wpkh(tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK/1/2/*)"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(desc.is_ok());
 
         let desc = "wpkh(tprv8ZgxMBicQKsPdpkqS7Eair4YxjcuuvDPNYmKX3sCniCf16tHEVrjjiSXEkFRnUH77yXc6ZcwHHcLNfjdi5qUvw3VDfgYiH5mNsj5izuiu2N/1/2/*)#67ju93jw"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(matches!(
             desc.err(),
             Some(DescriptorError::InvalidDescriptorChecksum)
         ));
 
         let desc = "wpkh(tprv8ZgxMBicQKsPdpkqS7Eair4YxjcuuvDPNYmKX3sCniCf16tHEVrjjiSXEkFRnUH77yXc6ZcwHHcLNfjdi5qUvw3VDfgYiH5mNsj5izuiu2N/1/2/*)#67ju93jw"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(matches!(
             desc.err(),
             Some(DescriptorError::InvalidDescriptorChecksum)
         ));
     }
 
-    // test ToWalletDescriptor trait from &str with keys from right and wrong network
+    // test IntoWalletDescriptor trait from &str with keys from right and wrong network
     #[test]
     fn test_descriptor_from_str_with_keys_network() {
+        let secp = Secp256k1::new();
+
         let desc = "wpkh(tprv8ZgxMBicQKsPdpkqS7Eair4YxjcuuvDPNYmKX3sCniCf16tHEVrjjiSXEkFRnUH77yXc6ZcwHHcLNfjdi5qUvw3VDfgYiH5mNsj5izuiu2N/1/2/*)"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(desc.is_ok());
 
         let desc = "wpkh(tprv8ZgxMBicQKsPdpkqS7Eair4YxjcuuvDPNYmKX3sCniCf16tHEVrjjiSXEkFRnUH77yXc6ZcwHHcLNfjdi5qUvw3VDfgYiH5mNsj5izuiu2N/1/2/*)"
-            .to_wallet_descriptor(Network::Regtest);
+            .into_wallet_descriptor(&secp, Network::Regtest);
         assert!(desc.is_ok());
 
         let desc = "wpkh(tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK/1/2/*)"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(desc.is_ok());
 
         let desc = "wpkh(tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK/1/2/*)"
-            .to_wallet_descriptor(Network::Regtest);
+            .into_wallet_descriptor(&secp, Network::Regtest);
         assert!(desc.is_ok());
 
         let desc = "sh(wpkh(02864bb4ad00cefa806098a69e192bbda937494e69eb452b87bb3f20f6283baedb))"
-            .to_wallet_descriptor(Network::Testnet);
+            .into_wallet_descriptor(&secp, Network::Testnet);
         assert!(desc.is_ok());
 
         let desc = "sh(wpkh(02864bb4ad00cefa806098a69e192bbda937494e69eb452b87bb3f20f6283baedb))"
-            .to_wallet_descriptor(Network::Bitcoin);
+            .into_wallet_descriptor(&secp, Network::Bitcoin);
         assert!(desc.is_ok());
 
         let desc = "wpkh(tprv8ZgxMBicQKsPdpkqS7Eair4YxjcuuvDPNYmKX3sCniCf16tHEVrjjiSXEkFRnUH77yXc6ZcwHHcLNfjdi5qUvw3VDfgYiH5mNsj5izuiu2N/1/2/*)"
-            .to_wallet_descriptor(Network::Bitcoin);
+            .into_wallet_descriptor(&secp, Network::Bitcoin);
         assert!(matches!(
             desc.err(),
             Some(DescriptorError::Key(KeyError::InvalidNetwork))
         ));
 
         let desc = "wpkh(tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK/1/2/*)"
-            .to_wallet_descriptor(Network::Bitcoin);
+            .into_wallet_descriptor(&secp, Network::Bitcoin);
         assert!(matches!(
             desc.err(),
             Some(DescriptorError::Key(KeyError::InvalidNetwork))
         ));
     }
 
-    // test ToWalletDescriptor trait from the output of the descriptor!() macro
+    // test IntoWalletDescriptor trait from the output of the descriptor!() macro
     #[test]
     fn test_descriptor_from_str_from_output_of_macro() {
+        let secp = Secp256k1::new();
+
         let tpub = bip32::ExtendedPubKey::from_str("tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK").unwrap();
         let path = bip32::DerivationPath::from_str("m/1/2").unwrap();
-        let key = (tpub, path).to_descriptor_key().unwrap();
+        let key = (tpub, path).into_descriptor_key().unwrap();
 
         // make a descriptor out of it
         let desc = crate::descriptor!(wpkh(key)).unwrap();
 
-        let (wallet_desc, _) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
+        let (wallet_desc, _) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
         let wallet_desc_str = wallet_desc.to_string();
-        assert_eq!(wallet_desc_str, "wpkh(tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK/1/2/*)");
+        assert_eq!(wallet_desc_str, "wpkh(tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK/1/2/*)#67ju93jw");
 
         let (wallet_desc2, _) = wallet_desc_str
-            .to_wallet_descriptor(Network::Testnet)
+            .into_wallet_descriptor(&secp, Network::Testnet)
             .unwrap();
         assert_eq!(wallet_desc, wallet_desc2)
     }
+
+    #[test]
+    fn test_into_wallet_descriptor_checked() {
+        let secp = Secp256k1::new();
+
+        let descriptor = "wpkh(tpubD6NzVbkrYhZ4XHndKkuB8FifXm8r5FQHwrN6oZuWCz13qb93rtgKvD4PQsqC4HP4yhV3tA2fqr2RbY5mNXfM7RxXUoeABoDtsFUq2zJq6YK/0'/1/2/*)";
+        let result = into_wallet_descriptor_checked(descriptor, &secp, Network::Testnet);
+
+        assert!(result.is_err());
+        assert!(matches!(
+            result.unwrap_err(),
+            DescriptorError::HardenedDerivationXpub
+        ));
+    }
 }

src/descriptor/policy.rs

@@ -38,7 +38,7 @@
 //! let secp = Secp256k1::new();
 //! let desc = "wsh(and_v(v:pk(cV3oCth6zxZ1UVsHLnGothsWNsaoxRhC6aeNi5VbSdFpwUkgkEci),or_d(pk(cVMTy7uebJgvFaSBwcgvwk8qn8xSLc97dKow4MBetjrrahZoimm2),older(12960))))";
 //!
-//! let (extended_desc, key_map) = ExtendedDescriptor::parse_descriptor(desc)?;
+//! let (extended_desc, key_map) = ExtendedDescriptor::parse_descriptor(&secp, desc)?;
 //! println!("{:?}", extended_desc);
 //!
 //! let signers = Arc::new(key_map.into());
@@ -47,7 +47,7 @@
 //! # Ok::<(), bdk::Error>(())
 //! ```
 
-use std::cmp::{max, Ordering};
+use std::cmp::max;
 use std::collections::{BTreeMap, HashSet, VecDeque};
 use std::fmt;
 
@@ -58,15 +58,15 @@ use bitcoin::hashes::*;
 use bitcoin::util::bip32::Fingerprint;
 use bitcoin::PublicKey;
 
-use miniscript::descriptor::{DescriptorPublicKey, SortedMultiVec};
+use miniscript::descriptor::{DescriptorPublicKey, ShInner, SortedMultiVec, WshInner};
 use miniscript::{Descriptor, Miniscript, MiniscriptKey, ScriptContext, Terminal, ToPublicKey};
 
 #[allow(unused_imports)]
 use log::{debug, error, info, trace};
 
-use crate::descriptor::ExtractPolicy;
+use crate::descriptor::{DerivedDescriptorKey, ExtractPolicy};
 use crate::wallet::signer::{SignerId, SignersContainer};
-use crate::wallet::utils::{self, descriptor_to_pk_ctx, SecpCtx};
+use crate::wallet::utils::{self, SecpCtx};
 
 use super::checksum::get_checksum;
 use super::error::Error;
@@ -354,7 +354,7 @@ impl Satisfaction {
         }
     }
 
-    fn finalize(&mut self) -> Result<(), PolicyError> {
+    fn finalize(&mut self) {
         // if partial try to bump it to a partialcomplete
         if let Satisfaction::Partial {
             n,
@@ -420,8 +420,6 @@ impl Satisfaction {
                 };
             }
         }
-
-        Ok(())
     }
 }
 
@@ -508,13 +506,11 @@ impl Condition {
 }
 
 /// Errors that can happen while extracting and manipulating policies
-#[derive(Debug)]
+#[derive(Debug, PartialEq, Eq)]
 pub enum PolicyError {
-    /// Not enough items are selected to satisfy a [`SatisfiableItem::Thresh`]
+    /// Not enough items are selected to satisfy a [`SatisfiableItem::Thresh`] or a [`SatisfiableItem::Multisig`]
     NotEnoughItemsSelected(String),
-    /// Too many items are selected to satisfy a [`SatisfiableItem::Thresh`]
-    TooManyItemsSelected(String),
-    /// Index out of range for an item to satisfy a [`SatisfiableItem::Thresh`]
+    /// Index out of range for an item to satisfy a [`SatisfiableItem::Thresh`] or a [`SatisfiableItem::Multisig`]
     IndexOutOfRange(usize),
     /// Can not add to an item that is [`Satisfaction::None`] or [`Satisfaction::Complete`]
     AddOnLeaf,
@@ -575,7 +571,7 @@ impl Policy {
         for (index, item) in items.iter().enumerate() {
             contribution.add(&item.contribution, index)?;
         }
-        contribution.finalize()?;
+        contribution.finalize();
 
         let mut policy: Policy = SatisfiableItem::Thresh { items, threshold }.into();
         policy.contribution = contribution;
@@ -613,7 +609,7 @@ impl Policy {
                 )?;
             }
         }
-        contribution.finalize()?;
+        contribution.finalize();
 
         let mut policy: Policy = SatisfiableItem::Multisig {
             keys: parsed_keys,
@@ -646,10 +642,10 @@ impl Policy {
             SatisfiableItem::Thresh { items, threshold } if items.len() == *threshold => {
                 (0..*threshold).collect()
             }
+            SatisfiableItem::Multisig { keys, .. } => (0..keys.len()).collect(),
             _ => vec![],
         };
         let selected = match path.get(&self.id) {
-            _ if !default.is_empty() => &default,
             Some(arr) => arr,
             _ => &default,
         };
@@ -670,14 +666,8 @@ impl Policy {
                 // if we have something, make sure we have enough items. note that the user can set
                 // an empty value for this step in case of n-of-n, because `selected` is set to all
                 // the elements above
-                match selected.len().cmp(threshold) {
-                    Ordering::Less => {
-                        return Err(PolicyError::NotEnoughItemsSelected(self.id.clone()))
-                    }
-                    Ordering::Greater => {
-                        return Err(PolicyError::TooManyItemsSelected(self.id.clone()))
-                    }
-                    Ordering::Equal => (),
+                if selected.len() < *threshold {
+                    return Err(PolicyError::NotEnoughItemsSelected(self.id.clone()));
                 }
 
                 // check the selected items, see if there are conflicting requirements
@@ -692,7 +682,16 @@ impl Policy {
 
                 Ok(requirements)
             }
-            _ if !selected.is_empty() => Err(PolicyError::TooManyItemsSelected(self.id.clone())),
+            SatisfiableItem::Multisig { keys, threshold } => {
+                if selected.len() < *threshold {
+                    return Err(PolicyError::NotEnoughItemsSelected(self.id.clone()));
+                }
+                if let Some(item) = selected.iter().find(|i| **i >= keys.len()) {
+                    return Err(PolicyError::IndexOutOfRange(*item));
+                }
+
+                Ok(Condition::default())
+            }
             SatisfiableItem::AbsoluteTimelock { value } => Ok(Condition {
                 csv: None,
                 timelock: Some(*value),
@@ -738,8 +737,9 @@ fn signature_key(
     signers: &SignersContainer,
     secp: &SecpCtx,
 ) -> Policy {
-    let deriv_ctx = descriptor_to_pk_ctx(secp);
-    let key_hash = key.to_public_key(deriv_ctx).to_pubkeyhash();
+    let key_hash = DerivedDescriptorKey::new(key.clone(), secp)
+        .to_public_key()
+        .to_pubkeyhash();
     let mut policy: Policy = SatisfiableItem::Signature(PKOrF::from_key_hash(key_hash)).into();
 
     if signers.find(SignerId::PkHash(key_hash)).is_some() {
@@ -866,38 +866,37 @@ impl ExtractPolicy for Descriptor<DescriptorPublicKey> {
         }
 
         match self {
-            Descriptor::Pk(pubkey)
-            | Descriptor::Pkh(pubkey)
-            | Descriptor::Wpkh(pubkey)
-            | Descriptor::ShWpkh(pubkey) => Ok(Some(signature(pubkey, signers, secp))),
-            Descriptor::Bare(inner) => Ok(inner.extract_policy(signers, secp)?),
-            Descriptor::Sh(inner) => Ok(inner.extract_policy(signers, secp)?),
-            Descriptor::Wsh(inner) | Descriptor::ShWsh(inner) => {
-                Ok(inner.extract_policy(signers, secp)?)
-            }
-
-            // `sortedmulti()` is handled separately
-            Descriptor::ShSortedMulti(keys) => make_sortedmulti(&keys, signers, secp),
-            Descriptor::ShWshSortedMulti(keys) | Descriptor::WshSortedMulti(keys) => {
-                make_sortedmulti(&keys, signers, secp)
-            }
+            Descriptor::Pkh(pk) => Ok(Some(signature(pk.as_inner(), signers, secp))),
+            Descriptor::Wpkh(pk) => Ok(Some(signature(pk.as_inner(), signers, secp))),
+            Descriptor::Sh(sh) => match sh.as_inner() {
+                ShInner::Wpkh(pk) => Ok(Some(signature(pk.as_inner(), signers, secp))),
+                ShInner::Ms(ms) => Ok(ms.extract_policy(signers, secp)?),
+                ShInner::SortedMulti(ref keys) => make_sortedmulti(keys, signers, secp),
+                ShInner::Wsh(wsh) => match wsh.as_inner() {
+                    WshInner::Ms(ms) => Ok(ms.extract_policy(signers, secp)?),
+                    WshInner::SortedMulti(ref keys) => make_sortedmulti(keys, signers, secp),
+                },
+            },
+            Descriptor::Wsh(wsh) => match wsh.as_inner() {
+                WshInner::Ms(ms) => Ok(ms.extract_policy(signers, secp)?),
+                WshInner::SortedMulti(ref keys) => make_sortedmulti(keys, signers, secp),
+            },
+            Descriptor::Bare(ms) => Ok(ms.as_inner().extract_policy(signers, secp)?),
         }
     }
 }
 
 #[cfg(test)]
 mod test {
-
     use crate::descriptor;
-    use crate::descriptor::{ExtractPolicy, ToWalletDescriptor};
+    use crate::descriptor::{ExtractPolicy, IntoWalletDescriptor};
 
     use super::*;
     use crate::descriptor::policy::SatisfiableItem::{Multisig, Signature, Thresh};
-    use crate::keys::{DescriptorKey, ToDescriptorKey};
+    use crate::keys::{DescriptorKey, IntoDescriptorKey};
     use crate::wallet::signer::SignersContainer;
     use bitcoin::secp256k1::{All, Secp256k1};
     use bitcoin::util::bip32;
-    use bitcoin::util::bip32::ChildNumber;
     use bitcoin::Network;
     use std::str::FromStr;
     use std::sync::Arc;
@@ -915,8 +914,8 @@ mod test {
         let tprv = bip32::ExtendedPrivKey::from_str(tprv).unwrap();
         let tpub = bip32::ExtendedPubKey::from_private(&secp, &tprv);
         let fingerprint = tprv.fingerprint(&secp);
-        let prvkey = (tprv, path.clone()).to_descriptor_key().unwrap();
-        let pubkey = (tpub, path).to_descriptor_key().unwrap();
+        let prvkey = (tprv, path.clone()).into_descriptor_key().unwrap();
+        let pubkey = (tpub, path).into_descriptor_key().unwrap();
 
         (prvkey, pubkey, fingerprint)
     }
@@ -925,9 +924,13 @@ mod test {
 
     #[test]
     fn test_extract_policy_for_wpkh() {
+        let secp = Secp256k1::new();
+
         let (prvkey, pubkey, fingerprint) = setup_keys(TPRV0_STR);
         let desc = descriptor!(wpkh(pubkey)).unwrap();
-        let (wallet_desc, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
         let signers_container = Arc::new(SignersContainer::from(keymap));
         let policy = wallet_desc
             .extract_policy(&signers_container, &Secp256k1::new())
@@ -940,7 +943,9 @@ mod test {
         assert!(matches!(&policy.contribution, Satisfaction::None));
 
         let desc = descriptor!(wpkh(prvkey)).unwrap();
-        let (wallet_desc, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
         let signers_container = Arc::new(SignersContainer::from(keymap));
         let policy = wallet_desc
             .extract_policy(&signers_container, &Secp256k1::new())
@@ -1018,10 +1023,14 @@ mod test {
     #[test]
     #[ignore] // see https://github.com/bitcoindevkit/bdk/issues/225
     fn test_extract_policy_for_sh_multi_complete_1of2() {
+        let secp = Secp256k1::new();
+
         let (_prvkey0, pubkey0, fingerprint0) = setup_keys(TPRV0_STR);
         let (prvkey1, _pubkey1, fingerprint1) = setup_keys(TPRV1_STR);
         let desc = descriptor!(sh(multi(1, pubkey0, prvkey1))).unwrap();
-        let (wallet_desc, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
         let signers_container = Arc::new(SignersContainer::from(keymap));
         let policy = wallet_desc
             .extract_policy(&signers_container, &Secp256k1::new())
@@ -1046,10 +1055,14 @@ mod test {
     // 2 prv keys descriptor, required 2 prv keys
     #[test]
     fn test_extract_policy_for_sh_multi_complete_2of2() {
+        let secp = Secp256k1::new();
+
         let (prvkey0, _pubkey0, fingerprint0) = setup_keys(TPRV0_STR);
         let (prvkey1, _pubkey1, fingerprint1) = setup_keys(TPRV1_STR);
         let desc = descriptor!(sh(multi(2, prvkey0, prvkey1))).unwrap();
-        let (wallet_desc, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
         let signers_container = Arc::new(SignersContainer::from(keymap));
         let policy = wallet_desc
             .extract_policy(&signers_container, &Secp256k1::new())
@@ -1075,10 +1088,14 @@ mod test {
 
     #[test]
     fn test_extract_policy_for_single_wpkh() {
+        let secp = Secp256k1::new();
+
         let (prvkey, pubkey, fingerprint) = setup_keys(TPRV0_STR);
         let desc = descriptor!(wpkh(pubkey)).unwrap();
-        let (wallet_desc, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
-        let single_key = wallet_desc.derive(ChildNumber::from_normal_idx(0).unwrap());
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
+        let single_key = wallet_desc.derive(0);
         let signers_container = Arc::new(SignersContainer::from(keymap));
         let policy = single_key
             .extract_policy(&signers_container, &Secp256k1::new())
@@ -1091,8 +1108,10 @@ mod test {
         assert!(matches!(&policy.contribution, Satisfaction::None));
 
         let desc = descriptor!(wpkh(prvkey)).unwrap();
-        let (wallet_desc, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
-        let single_key = wallet_desc.derive(ChildNumber::from_normal_idx(0).unwrap());
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
+        let single_key = wallet_desc.derive(0);
         let signers_container = Arc::new(SignersContainer::from(keymap));
         let policy = single_key
             .extract_policy(&signers_container, &Secp256k1::new())
@@ -1111,11 +1130,15 @@ mod test {
     #[test]
     #[ignore] // see https://github.com/bitcoindevkit/bdk/issues/225
     fn test_extract_policy_for_single_wsh_multi_complete_1of2() {
+        let secp = Secp256k1::new();
+
         let (_prvkey0, pubkey0, fingerprint0) = setup_keys(TPRV0_STR);
         let (prvkey1, _pubkey1, fingerprint1) = setup_keys(TPRV1_STR);
         let desc = descriptor!(sh(multi(1, pubkey0, prvkey1))).unwrap();
-        let (wallet_desc, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
-        let single_key = wallet_desc.derive(ChildNumber::from_normal_idx(0).unwrap());
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
+        let single_key = wallet_desc.derive(0);
         let signers_container = Arc::new(SignersContainer::from(keymap));
         let policy = single_key
             .extract_policy(&signers_container, &Secp256k1::new())
@@ -1142,6 +1165,8 @@ mod test {
     #[test]
     #[ignore] // see https://github.com/bitcoindevkit/bdk/issues/225
     fn test_extract_policy_for_wsh_multi_timelock() {
+        let secp = Secp256k1::new();
+
         let (prvkey0, _pubkey0, _fingerprint0) = setup_keys(TPRV0_STR);
         let (_prvkey1, pubkey1, _fingerprint1) = setup_keys(TPRV1_STR);
         let sequence = 50;
@@ -1154,7 +1179,9 @@ mod test {
         )))
         .unwrap();
 
-        let (wallet_desc, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
         let signers_container = Arc::new(SignersContainer::from(keymap));
         let policy = wallet_desc
             .extract_policy(&signers_container, &Secp256k1::new())
@@ -1231,4 +1258,50 @@ mod test {
     //
     //     // TODO how should this merge timelocks?
     // }
+
+    #[test]
+    fn test_get_condition_multisig() {
+        let secp = Secp256k1::gen_new();
+
+        let (_, pk0, _) = setup_keys(TPRV0_STR);
+        let (_, pk1, _) = setup_keys(TPRV1_STR);
+
+        let desc = descriptor!(wsh(multi(1, pk0, pk1))).unwrap();
+        let (wallet_desc, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
+        let signers = keymap.into();
+
+        let policy = wallet_desc
+            .extract_policy(&signers, &secp)
+            .unwrap()
+            .unwrap();
+
+        // no args, choose the default
+        let no_args = policy.get_condition(&vec![].into_iter().collect());
+        assert_eq!(no_args, Ok(Condition::default()));
+
+        // enough args
+        let eq_thresh =
+            policy.get_condition(&vec![(policy.id.clone(), vec![0])].into_iter().collect());
+        assert_eq!(eq_thresh, Ok(Condition::default()));
+
+        // more args, it doesn't really change anything
+        let gt_thresh =
+            policy.get_condition(&vec![(policy.id.clone(), vec![0, 1])].into_iter().collect());
+        assert_eq!(gt_thresh, Ok(Condition::default()));
+
+        // not enough args, error
+        let lt_thresh =
+            policy.get_condition(&vec![(policy.id.clone(), vec![])].into_iter().collect());
+        assert_eq!(
+            lt_thresh,
+            Err(PolicyError::NotEnoughItemsSelected(policy.id.clone()))
+        );
+
+        // index out of range
+        let out_of_range =
+            policy.get_condition(&vec![(policy.id.clone(), vec![5])].into_iter().collect());
+        assert_eq!(out_of_range, Err(PolicyError::IndexOutOfRange(5)));
+    }
 }

src/descriptor/template.rs

@@ -32,9 +32,10 @@ use bitcoin::Network;
 
 use miniscript::{Legacy, Segwitv0};
 
-use super::{ExtendedDescriptor, KeyMap, ToWalletDescriptor};
+use super::{ExtendedDescriptor, IntoWalletDescriptor, KeyMap};
 use crate::descriptor::DescriptorError;
-use crate::keys::{DerivableKey, ToDescriptorKey, ValidNetworks};
+use crate::keys::{DerivableKey, IntoDescriptorKey, ValidNetworks};
+use crate::wallet::utils::SecpCtx;
 use crate::{descriptor, KeychainKind};
 
 /// Type alias for the return type of [`DescriptorTemplate`], [`descriptor!`](crate::descriptor!) and others
@@ -42,20 +43,20 @@ pub type DescriptorTemplateOut = (ExtendedDescriptor, KeyMap, ValidNetworks);
 
 /// Trait for descriptor templates that can be built into a full descriptor
 ///
-/// Since [`ToWalletDescriptor`] is implemented for any [`DescriptorTemplate`], they can also be
+/// Since [`IntoWalletDescriptor`] is implemented for any [`DescriptorTemplate`], they can also be
 /// passed directly to the [`Wallet`](crate::Wallet) constructor.
 ///
 /// ## Example
 ///
 /// ```
 /// use bdk::descriptor::error::Error as DescriptorError;
-/// use bdk::keys::{KeyError, ToDescriptorKey};
+/// use bdk::keys::{KeyError, IntoDescriptorKey};
 /// use bdk::miniscript::Legacy;
 /// use bdk::template::{DescriptorTemplate, DescriptorTemplateOut};
 ///
-/// struct MyP2PKH<K: ToDescriptorKey<Legacy>>(K);
+/// struct MyP2PKH<K: IntoDescriptorKey<Legacy>>(K);
 ///
-/// impl<K: ToDescriptorKey<Legacy>> DescriptorTemplate for MyP2PKH<K> {
+/// impl<K: IntoDescriptorKey<Legacy>> DescriptorTemplate for MyP2PKH<K> {
 ///     fn build(self) -> Result<DescriptorTemplateOut, DescriptorError> {
 ///         Ok(bdk::descriptor!(pkh(self.0))?)
 ///     }
@@ -68,12 +69,13 @@ pub trait DescriptorTemplate {
 
 /// Turns a [`DescriptorTemplate`] into a valid wallet descriptor by calling its
 /// [`build`](DescriptorTemplate::build) method
-impl<T: DescriptorTemplate> ToWalletDescriptor for T {
-    fn to_wallet_descriptor(
+impl<T: DescriptorTemplate> IntoWalletDescriptor for T {
+    fn into_wallet_descriptor(
         self,
+        secp: &SecpCtx,
         network: Network,
     ) -> Result<(ExtendedDescriptor, KeyMap), DescriptorError> {
-        Ok(self.build()?.to_wallet_descriptor(network)?)
+        Ok(self.build()?.into_wallet_descriptor(secp, network)?)
     }
 }
 
@@ -102,9 +104,9 @@ impl<T: DescriptorTemplate> ToWalletDescriptor for T {
 /// );
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
-pub struct P2PKH<K: ToDescriptorKey<Legacy>>(pub K);
+pub struct P2PKH<K: IntoDescriptorKey<Legacy>>(pub K);
 
-impl<K: ToDescriptorKey<Legacy>> DescriptorTemplate for P2PKH<K> {
+impl<K: IntoDescriptorKey<Legacy>> DescriptorTemplate for P2PKH<K> {
     fn build(self) -> Result<DescriptorTemplateOut, DescriptorError> {
         Ok(descriptor!(pkh(self.0))?)
     }
@@ -136,9 +138,9 @@ impl<K: ToDescriptorKey<Legacy>> DescriptorTemplate for P2PKH<K> {
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
 #[allow(non_camel_case_types)]
-pub struct P2WPKH_P2SH<K: ToDescriptorKey<Segwitv0>>(pub K);
+pub struct P2WPKH_P2SH<K: IntoDescriptorKey<Segwitv0>>(pub K);
 
-impl<K: ToDescriptorKey<Segwitv0>> DescriptorTemplate for P2WPKH_P2SH<K> {
+impl<K: IntoDescriptorKey<Segwitv0>> DescriptorTemplate for P2WPKH_P2SH<K> {
     fn build(self) -> Result<DescriptorTemplateOut, DescriptorError> {
         Ok(descriptor!(sh(wpkh(self.0)))?)
     }
@@ -169,9 +171,9 @@ impl<K: ToDescriptorKey<Segwitv0>> DescriptorTemplate for P2WPKH_P2SH<K> {
 /// );
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
-pub struct P2WPKH<K: ToDescriptorKey<Segwitv0>>(pub K);
+pub struct P2WPKH<K: IntoDescriptorKey<Segwitv0>>(pub K);
 
-impl<K: ToDescriptorKey<Segwitv0>> DescriptorTemplate for P2WPKH<K> {
+impl<K: IntoDescriptorKey<Segwitv0>> DescriptorTemplate for P2WPKH<K> {
     fn build(self) -> Result<DescriptorTemplateOut, DescriptorError> {
         Ok(descriptor!(wpkh(self.0))?)
     }
@@ -201,7 +203,7 @@ impl<K: ToDescriptorKey<Segwitv0>> DescriptorTemplate for P2WPKH<K> {
 /// )?;
 ///
 /// assert_eq!(wallet.get_new_address()?.to_string(), "miNG7dJTzJqNbFS19svRdTCisC65dsubtR");
-/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "pkh([c55b303f/44'/0'/0']tpubDDDzQ31JkZB7VxUr9bjvBivDdqoFLrDPyLWtLapArAi51ftfmCb2DPxwLQzX65iNcXz1DGaVvyvo6JQ6rTU73r2gqdEo8uov9QKRb7nKCSU/0/*)");
+/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "pkh([c55b303f/44'/0'/0']tpubDDDzQ31JkZB7VxUr9bjvBivDdqoFLrDPyLWtLapArAi51ftfmCb2DPxwLQzX65iNcXz1DGaVvyvo6JQ6rTU73r2gqdEo8uov9QKRb7nKCSU/0/*)#xgaaevjx");
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
 pub struct BIP44<K: DerivableKey<Legacy>>(pub K, pub KeychainKind);
@@ -240,7 +242,7 @@ impl<K: DerivableKey<Legacy>> DescriptorTemplate for BIP44<K> {
 /// )?;
 ///
 /// assert_eq!(wallet.get_new_address()?.to_string(), "miNG7dJTzJqNbFS19svRdTCisC65dsubtR");
-/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "pkh([c55b303f/44'/0'/0']tpubDDDzQ31JkZB7VxUr9bjvBivDdqoFLrDPyLWtLapArAi51ftfmCb2DPxwLQzX65iNcXz1DGaVvyvo6JQ6rTU73r2gqdEo8uov9QKRb7nKCSU/0/*)");
+/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "pkh([c55b303f/44'/0'/0']tpubDDDzQ31JkZB7VxUr9bjvBivDdqoFLrDPyLWtLapArAi51ftfmCb2DPxwLQzX65iNcXz1DGaVvyvo6JQ6rTU73r2gqdEo8uov9QKRb7nKCSU/0/*)#xgaaevjx");
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
 pub struct BIP44Public<K: DerivableKey<Legacy>>(pub K, pub bip32::Fingerprint, pub KeychainKind);
@@ -275,7 +277,7 @@ impl<K: DerivableKey<Legacy>> DescriptorTemplate for BIP44Public<K> {
 /// )?;
 ///
 /// assert_eq!(wallet.get_new_address()?.to_string(), "2N3K4xbVAHoiTQSwxkZjWDfKoNC27pLkYnt");
-/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "sh(wpkh([c55b303f/49\'/0\'/0\']tpubDC49r947KGK52X5rBWS4BLs5m9SRY3pYHnvRrm7HcybZ3BfdEsGFyzCMzayi1u58eT82ZeyFZwH7DD6Q83E3fM9CpfMtmnTygnLfP59jL9L/0/*))");
+/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "sh(wpkh([c55b303f/49\'/0\'/0\']tpubDC49r947KGK52X5rBWS4BLs5m9SRY3pYHnvRrm7HcybZ3BfdEsGFyzCMzayi1u58eT82ZeyFZwH7DD6Q83E3fM9CpfMtmnTygnLfP59jL9L/0/*))#gsmdv4xr");
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
 pub struct BIP49<K: DerivableKey<Segwitv0>>(pub K, pub KeychainKind);
@@ -314,7 +316,7 @@ impl<K: DerivableKey<Segwitv0>> DescriptorTemplate for BIP49<K> {
 /// )?;
 ///
 /// assert_eq!(wallet.get_new_address()?.to_string(), "2N3K4xbVAHoiTQSwxkZjWDfKoNC27pLkYnt");
-/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "sh(wpkh([c55b303f/49\'/0\'/0\']tpubDC49r947KGK52X5rBWS4BLs5m9SRY3pYHnvRrm7HcybZ3BfdEsGFyzCMzayi1u58eT82ZeyFZwH7DD6Q83E3fM9CpfMtmnTygnLfP59jL9L/0/*))");
+/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "sh(wpkh([c55b303f/49\'/0\'/0\']tpubDC49r947KGK52X5rBWS4BLs5m9SRY3pYHnvRrm7HcybZ3BfdEsGFyzCMzayi1u58eT82ZeyFZwH7DD6Q83E3fM9CpfMtmnTygnLfP59jL9L/0/*))#gsmdv4xr");
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
 pub struct BIP49Public<K: DerivableKey<Segwitv0>>(pub K, pub bip32::Fingerprint, pub KeychainKind);
@@ -349,7 +351,7 @@ impl<K: DerivableKey<Segwitv0>> DescriptorTemplate for BIP49Public<K> {
 /// )?;
 ///
 /// assert_eq!(wallet.get_new_address()?.to_string(), "tb1qedg9fdlf8cnnqfd5mks6uz5w4kgpk2pr6y4qc7");
-/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "wpkh([c55b303f/84\'/0\'/0\']tpubDC2Qwo2TFsaNC4ju8nrUJ9mqVT3eSgdmy1yPqhgkjwmke3PRXutNGRYAUo6RCHTcVQaDR3ohNU9we59brGHuEKPvH1ags2nevW5opEE9Z5Q/0/*)");
+/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "wpkh([c55b303f/84\'/0\'/0\']tpubDC2Qwo2TFsaNC4ju8nrUJ9mqVT3eSgdmy1yPqhgkjwmke3PRXutNGRYAUo6RCHTcVQaDR3ohNU9we59brGHuEKPvH1ags2nevW5opEE9Z5Q/0/*)#nkk5dtkg");
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
 pub struct BIP84<K: DerivableKey<Segwitv0>>(pub K, pub KeychainKind);
@@ -388,7 +390,7 @@ impl<K: DerivableKey<Segwitv0>> DescriptorTemplate for BIP84<K> {
 /// )?;
 ///
 /// assert_eq!(wallet.get_new_address()?.to_string(), "tb1qedg9fdlf8cnnqfd5mks6uz5w4kgpk2pr6y4qc7");
-/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "wpkh([c55b303f/84\'/0\'/0\']tpubDC2Qwo2TFsaNC4ju8nrUJ9mqVT3eSgdmy1yPqhgkjwmke3PRXutNGRYAUo6RCHTcVQaDR3ohNU9we59brGHuEKPvH1ags2nevW5opEE9Z5Q/0/*)");
+/// assert_eq!(wallet.public_descriptor(KeychainKind::External)?.unwrap().to_string(), "wpkh([c55b303f/84\'/0\'/0\']tpubDC2Qwo2TFsaNC4ju8nrUJ9mqVT3eSgdmy1yPqhgkjwmke3PRXutNGRYAUo6RCHTcVQaDR3ohNU9we59brGHuEKPvH1ags2nevW5opEE9Z5Q/0/*)#nkk5dtkg");
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
 pub struct BIP84Public<K: DerivableKey<Segwitv0>>(pub K, pub bip32::Fingerprint, pub KeychainKind);
@@ -408,7 +410,7 @@ macro_rules! expand_make_bipxx {
                 bip: u32,
                 key: K,
                 keychain: KeychainKind,
-            ) -> Result<impl ToDescriptorKey<$ctx>, DescriptorError> {
+            ) -> Result<impl IntoDescriptorKey<$ctx>, DescriptorError> {
                 let mut derivation_path = Vec::with_capacity(4);
                 derivation_path.push(bip32::ChildNumber::from_hardened_idx(bip)?);
                 derivation_path.push(bip32::ChildNumber::from_hardened_idx(0)?);
@@ -432,7 +434,7 @@ macro_rules! expand_make_bipxx {
                 key: K,
                 parent_fingerprint: bip32::Fingerprint,
                 keychain: KeychainKind,
-            ) -> Result<impl ToDescriptorKey<$ctx>, DescriptorError> {
+            ) -> Result<impl IntoDescriptorKey<$ctx>, DescriptorError> {
                 let derivation_path: bip32::DerivationPath = match keychain {
                     KeychainKind::External => vec![bip32::ChildNumber::from_normal_idx(0)?].into(),
                     KeychainKind::Internal => vec![bip32::ChildNumber::from_normal_idx(1)?].into(),
@@ -458,13 +460,13 @@ mod test {
     // test existing descriptor templates, make sure they are expanded to the right descriptors
 
     use super::*;
+    use crate::descriptor::derived::AsDerived;
     use crate::descriptor::{DescriptorError, DescriptorMeta};
     use crate::keys::ValidNetworks;
     use bitcoin::hashes::core::str::FromStr;
     use bitcoin::network::constants::Network::Regtest;
     use bitcoin::secp256k1::Secp256k1;
-    use bitcoin::util::bip32::ChildNumber;
-    use miniscript::descriptor::{DescriptorPublicKey, DescriptorPublicKeyCtx, KeyMap};
+    use miniscript::descriptor::{DescriptorPublicKey, DescriptorTrait, KeyMap};
     use miniscript::Descriptor;
 
     // verify template descriptor generates expected address(es)
@@ -475,20 +477,18 @@ mod test {
         expected: &[&str],
     ) {
         let secp = Secp256k1::new();
-        let deriv_ctx =
-            DescriptorPublicKeyCtx::new(&secp, ChildNumber::from_normal_idx(0).unwrap());
 
         let (desc, _key_map, _networks) = desc.unwrap();
         assert_eq!(desc.is_witness(), is_witness);
-        assert_eq!(desc.is_fixed(), is_fixed);
+        assert_eq!(!desc.is_deriveable(), is_fixed);
         for i in 0..expected.len() {
             let index = i as u32;
-            let child_desc = if desc.is_fixed() {
-                desc.clone()
+            let child_desc = if !desc.is_deriveable() {
+                desc.as_derived_fixed(&secp)
             } else {
-                desc.derive(ChildNumber::from_normal_idx(index).unwrap())
+                desc.as_derived(index, &secp)
             };
-            let address = child_desc.address(Regtest, deriv_ctx).unwrap();
+            let address = child_desc.address(Regtest).unwrap();
             assert_eq!(address.to_string(), *expected.get(i).unwrap());
         }
     }

src/keys/bip39.rs

@@ -32,51 +32,81 @@ use bitcoin::Network;
 
 use miniscript::ScriptContext;
 
-use bip39::{Language, Mnemonic, MnemonicType, Seed};
+pub use bip39::{Language, Mnemonic, MnemonicType, Seed};
 
-use super::{any_network, DerivableKey, DescriptorKey, GeneratableKey, GeneratedKey, KeyError};
+use super::{
+    any_network, DerivableKey, DescriptorKey, ExtendedKey, GeneratableKey, GeneratedKey, KeyError,
+};
+
+fn set_valid_on_any_network<Ctx: ScriptContext>(
+    descriptor_key: DescriptorKey<Ctx>,
+) -> DescriptorKey<Ctx> {
+    // We have to pick one network to build the xprv, but since the bip39 standard doesn't
+    // encode the network, the xprv we create is actually valid everywhere. So we override the
+    // valid networks with `any_network()`.
+    descriptor_key.override_valid_networks(any_network())
+}
 
 /// Type for a BIP39 mnemonic with an optional passphrase
 pub type MnemonicWithPassphrase = (Mnemonic, Option<String>);
 
 #[cfg_attr(docsrs, doc(cfg(feature = "keys-bip39")))]
 impl<Ctx: ScriptContext> DerivableKey<Ctx> for Seed {
-    fn add_metadata(
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+        Ok(bip32::ExtendedPrivKey::new_master(Network::Bitcoin, &self.as_bytes())?.into())
+    }
+
+    fn into_descriptor_key(
         self,
         source: Option<bip32::KeySource>,
         derivation_path: bip32::DerivationPath,
     ) -> Result<DescriptorKey<Ctx>, KeyError> {
-        let xprv = bip32::ExtendedPrivKey::new_master(Network::Bitcoin, &self.as_bytes())?;
-        let descriptor_key = xprv.add_metadata(source, derivation_path)?;
+        let descriptor_key = self
+            .into_extended_key()?
+            .into_descriptor_key(source, derivation_path)?;
 
-        // here we must choose one network to build the xpub, but since the bip39 standard doesn't
-        // encode the network, the xpub we create is actually valid everywhere. so we override the
-        // valid networks with `any_network()`.
-        Ok(descriptor_key.override_valid_networks(any_network()))
+        Ok(set_valid_on_any_network(descriptor_key))
     }
 }
 
 #[cfg_attr(docsrs, doc(cfg(feature = "keys-bip39")))]
 impl<Ctx: ScriptContext> DerivableKey<Ctx> for MnemonicWithPassphrase {
-    fn add_metadata(
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+        let (mnemonic, passphrase) = self;
+        let seed = Seed::new(&mnemonic, passphrase.as_deref().unwrap_or(""));
+
+        seed.into_extended_key()
+    }
+
+    fn into_descriptor_key(
         self,
         source: Option<bip32::KeySource>,
         derivation_path: bip32::DerivationPath,
     ) -> Result<DescriptorKey<Ctx>, KeyError> {
-        let (mnemonic, passphrase) = self;
-        let seed = Seed::new(&mnemonic, passphrase.as_deref().unwrap_or(""));
-        seed.add_metadata(source, derivation_path)
+        let descriptor_key = self
+            .into_extended_key()?
+            .into_descriptor_key(source, derivation_path)?;
+
+        Ok(set_valid_on_any_network(descriptor_key))
     }
 }
 
 #[cfg_attr(docsrs, doc(cfg(feature = "keys-bip39")))]
 impl<Ctx: ScriptContext> DerivableKey<Ctx> for Mnemonic {
-    fn add_metadata(
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+        (self, None).into_extended_key()
+    }
+
+    fn into_descriptor_key(
         self,
         source: Option<bip32::KeySource>,
         derivation_path: bip32::DerivationPath,
     ) -> Result<DescriptorKey<Ctx>, KeyError> {
-        (self, None).add_metadata(source, derivation_path)
+        let descriptor_key = self
+            .into_extended_key()?
+            .into_descriptor_key(source, derivation_path)?;
+
+        Ok(set_valid_on_any_network(descriptor_key))
     }
 }
 
@@ -117,9 +147,9 @@ mod test {
 
         let key = (mnemonic, path);
         let (desc, keys, networks) = crate::descriptor!(wpkh(key)).unwrap();
-        assert_eq!(desc.to_string(), "wpkh([be83839f/44'/0'/0']xpub6DCQ1YcqvZtSwGWMrwHELPehjWV3f2MGZ69yBADTxFEUAoLwb5Mp5GniQK6tTp3AgbngVz9zEFbBJUPVnkG7LFYt8QMTfbrNqs6FNEwAPKA/0/*)");
+        assert_eq!(desc.to_string(), "wpkh([be83839f/44'/0'/0']xpub6DCQ1YcqvZtSwGWMrwHELPehjWV3f2MGZ69yBADTxFEUAoLwb5Mp5GniQK6tTp3AgbngVz9zEFbBJUPVnkG7LFYt8QMTfbrNqs6FNEwAPKA/0/*)#0r8v4nkv");
         assert_eq!(keys.len(), 1);
-        assert_eq!(networks.len(), 3);
+        assert_eq!(networks.len(), 4);
     }
 
     #[test]
@@ -131,9 +161,9 @@ mod test {
 
         let key = ((mnemonic, Some("passphrase".into())), path);
         let (desc, keys, networks) = crate::descriptor!(wpkh(key)).unwrap();
-        assert_eq!(desc.to_string(), "wpkh([8f6cb80c/44'/0'/0']xpub6DWYS8bbihFevy29M4cbw4ZR3P5E12jB8R88gBDWCTCNpYiDHhYWNywrCF9VZQYagzPmsZpxXpytzSoxynyeFr4ZyzheVjnpLKuse4fiwZw/0/*)");
+        assert_eq!(desc.to_string(), "wpkh([8f6cb80c/44'/0'/0']xpub6DWYS8bbihFevy29M4cbw4ZR3P5E12jB8R88gBDWCTCNpYiDHhYWNywrCF9VZQYagzPmsZpxXpytzSoxynyeFr4ZyzheVjnpLKuse4fiwZw/0/*)#h0j0tg5m");
         assert_eq!(keys.len(), 1);
-        assert_eq!(networks.len(), 3);
+        assert_eq!(networks.len(), 4);
     }
 
     #[test]

src/keys/mod.rs

@@ -30,16 +30,16 @@ use std::marker::PhantomData;
 use std::ops::Deref;
 use std::str::FromStr;
 
-use bitcoin::secp256k1;
+use bitcoin::secp256k1::{self, Secp256k1, Signing};
 
 use bitcoin::util::bip32;
 use bitcoin::{Network, PrivateKey, PublicKey};
 
+use miniscript::descriptor::{Descriptor, DescriptorXKey, Wildcard};
 pub use miniscript::descriptor::{
-    DescriptorPublicKey, DescriptorSecretKey, DescriptorSinglePriv, DescriptorSinglePub,
+    DescriptorPublicKey, DescriptorSecretKey, DescriptorSinglePriv, DescriptorSinglePub, KeyMap,
     SortedMultiVec,
 };
-use miniscript::descriptor::{DescriptorXKey, KeyMap};
 pub use miniscript::ScriptContext;
 use miniscript::{Miniscript, Terminal};
 
@@ -55,9 +55,14 @@ pub type ValidNetworks = HashSet<Network>;
 
 /// Create a set containing mainnet, testnet and regtest
 pub fn any_network() -> ValidNetworks {
-    vec![Network::Bitcoin, Network::Testnet, Network::Regtest]
-        .into_iter()
-        .collect()
+    vec![
+        Network::Bitcoin,
+        Network::Testnet,
+        Network::Regtest,
+        Network::Signet,
+    ]
+    .into_iter()
+    .collect()
 }
 /// Create a set only containing mainnet
 pub fn mainnet_network() -> ValidNetworks {
@@ -65,7 +70,7 @@ pub fn mainnet_network() -> ValidNetworks {
 }
 /// Create a set containing testnet and regtest
 pub fn test_networks() -> ValidNetworks {
-    vec![Network::Testnet, Network::Regtest]
+    vec![Network::Testnet, Network::Regtest, Network::Signet]
         .into_iter()
         .collect()
 }
@@ -200,15 +205,15 @@ impl<Ctx: ScriptContext + 'static> ExtScriptContext for Ctx {
 /// ```
 /// use bdk::bitcoin::PublicKey;
 ///
-/// use bdk::keys::{DescriptorKey, KeyError, ScriptContext, ToDescriptorKey};
+/// use bdk::keys::{DescriptorKey, KeyError, ScriptContext, IntoDescriptorKey};
 ///
 /// pub struct MyKeyType {
 ///     pubkey: PublicKey,
 /// }
 ///
-/// impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for MyKeyType {
-///     fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
-///         self.pubkey.to_descriptor_key()
+/// impl<Ctx: ScriptContext> IntoDescriptorKey<Ctx> for MyKeyType {
+///     fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+///         self.pubkey.into_descriptor_key()
 ///     }
 /// }
 /// ```
@@ -220,15 +225,15 @@ impl<Ctx: ScriptContext + 'static> ExtScriptContext for Ctx {
 ///
 /// use bdk::keys::{
 ///     mainnet_network, DescriptorKey, DescriptorPublicKey, DescriptorSinglePub, KeyError,
-///     ScriptContext, ToDescriptorKey,
+///     ScriptContext, IntoDescriptorKey,
 /// };
 ///
 /// pub struct MyKeyType {
 ///     pubkey: PublicKey,
 /// }
 ///
-/// impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for MyKeyType {
-///     fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+/// impl<Ctx: ScriptContext> IntoDescriptorKey<Ctx> for MyKeyType {
+///     fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
 ///         Ok(DescriptorKey::from_public(
 ///             DescriptorPublicKey::SinglePub(DescriptorSinglePub {
 ///                 origin: None,
@@ -245,17 +250,17 @@ impl<Ctx: ScriptContext + 'static> ExtScriptContext for Ctx {
 /// ```
 /// use bdk::bitcoin::PublicKey;
 ///
-/// use bdk::keys::{DescriptorKey, ExtScriptContext, KeyError, ScriptContext, ToDescriptorKey};
+/// use bdk::keys::{DescriptorKey, ExtScriptContext, KeyError, ScriptContext, IntoDescriptorKey};
 ///
 /// pub struct MyKeyType {
 ///     is_legacy: bool,
 ///     pubkey: PublicKey,
 /// }
 ///
-/// impl<Ctx: ScriptContext + 'static> ToDescriptorKey<Ctx> for MyKeyType {
-///     fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+/// impl<Ctx: ScriptContext + 'static> IntoDescriptorKey<Ctx> for MyKeyType {
+///     fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
 ///         if Ctx::is_legacy() == self.is_legacy {
-///             self.pubkey.to_descriptor_key()
+///             self.pubkey.into_descriptor_key()
 ///         } else {
 ///             Err(KeyError::InvalidScriptContext)
 ///         }
@@ -274,15 +279,15 @@ impl<Ctx: ScriptContext + 'static> ExtScriptContext for Ctx {
 /// use bdk::bitcoin::PublicKey;
 /// use std::str::FromStr;
 ///
-/// use bdk::keys::{DescriptorKey, KeyError, ToDescriptorKey};
+/// use bdk::keys::{DescriptorKey, KeyError, IntoDescriptorKey};
 ///
 /// pub struct MySegwitOnlyKeyType {
 ///     pubkey: PublicKey,
 /// }
 ///
-/// impl ToDescriptorKey<bdk::miniscript::Segwitv0> for MySegwitOnlyKeyType {
-///     fn to_descriptor_key(self) -> Result<DescriptorKey<bdk::miniscript::Segwitv0>, KeyError> {
-///         self.pubkey.to_descriptor_key()
+/// impl IntoDescriptorKey<bdk::miniscript::Segwitv0> for MySegwitOnlyKeyType {
+///     fn into_descriptor_key(self) -> Result<DescriptorKey<bdk::miniscript::Segwitv0>, KeyError> {
+///         self.pubkey.into_descriptor_key()
 ///     }
 /// }
 ///
@@ -294,61 +299,234 @@ impl<Ctx: ScriptContext + 'static> ExtScriptContext for Ctx {
 ///
 /// # Ok::<_, Box<dyn std::error::Error>>(())
 /// ```
-pub trait ToDescriptorKey<Ctx: ScriptContext>: Sized {
+pub trait IntoDescriptorKey<Ctx: ScriptContext>: Sized {
     /// Turn the key into a [`DescriptorKey`] within the requested [`ScriptContext`]
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError>;
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError>;
+}
+
+/// Enum for extended keys that can be either `xprv` or `xpub`
+///
+/// An instance of [`ExtendedKey`] can be constructed from an [`ExtendedPrivKey`](bip32::ExtendedPrivKey)
+/// or an [`ExtendedPubKey`](bip32::ExtendedPubKey) by using the `From` trait.
+///
+/// Defaults to the [`Legacy`](miniscript::Legacy) context.
+pub enum ExtendedKey<Ctx: ScriptContext = miniscript::Legacy> {
+    /// A private extended key, aka an `xprv`
+    Private((bip32::ExtendedPrivKey, PhantomData<Ctx>)),
+    /// A public extended key, aka an `xpub`
+    Public((bip32::ExtendedPubKey, PhantomData<Ctx>)),
+}
+
+impl<Ctx: ScriptContext> ExtendedKey<Ctx> {
+    /// Return whether or not the key contains the private data
+    pub fn has_secret(&self) -> bool {
+        match self {
+            ExtendedKey::Private(_) => true,
+            ExtendedKey::Public(_) => false,
+        }
+    }
+
+    /// Transform the [`ExtendedKey`] into an [`ExtendedPrivKey`](bip32::ExtendedPrivKey) for the
+    /// given [`Network`], if the key contains the private data
+    pub fn into_xprv(self, network: Network) -> Option<bip32::ExtendedPrivKey> {
+        match self {
+            ExtendedKey::Private((mut xprv, _)) => {
+                xprv.network = network;
+                Some(xprv)
+            }
+            ExtendedKey::Public(_) => None,
+        }
+    }
+
+    /// Transform the [`ExtendedKey`] into an [`ExtendedPubKey`](bip32::ExtendedPubKey) for the
+    /// given [`Network`]
+    pub fn into_xpub<C: Signing>(
+        self,
+        network: bitcoin::Network,
+        secp: &Secp256k1<C>,
+    ) -> bip32::ExtendedPubKey {
+        let mut xpub = match self {
+            ExtendedKey::Private((xprv, _)) => bip32::ExtendedPubKey::from_private(secp, &xprv),
+            ExtendedKey::Public((xpub, _)) => xpub,
+        };
+
+        xpub.network = network;
+        xpub
+    }
+}
+
+impl<Ctx: ScriptContext> From<bip32::ExtendedPubKey> for ExtendedKey<Ctx> {
+    fn from(xpub: bip32::ExtendedPubKey) -> Self {
+        ExtendedKey::Public((xpub, PhantomData))
+    }
+}
+
+impl<Ctx: ScriptContext> From<bip32::ExtendedPrivKey> for ExtendedKey<Ctx> {
+    fn from(xprv: bip32::ExtendedPrivKey) -> Self {
+        ExtendedKey::Private((xprv, PhantomData))
+    }
 }
 
 /// Trait for keys that can be derived.
 ///
 /// When extra metadata are provided, a [`DerivableKey`] can be transofrmed into a
-/// [`DescriptorKey`]: the trait [`ToDescriptorKey`] is automatically implemented
+/// [`DescriptorKey`]: the trait [`IntoDescriptorKey`] is automatically implemented
 /// for `(DerivableKey, DerivationPath)` and
 /// `(DerivableKey, KeySource, DerivationPath)` tuples.
 ///
 /// For key types that don't encode any indication about the path to use (like bip39), it's
-/// generally recommended to implemented this trait instead of [`ToDescriptorKey`]. The same
+/// generally recommended to implemented this trait instead of [`IntoDescriptorKey`]. The same
 /// rules regarding script context and valid networks apply.
 ///
+/// ## Examples
+///
+/// Key types that can be directly converted into an [`ExtendedPrivKey`] or
+/// an [`ExtendedPubKey`] can implement only the required `into_extended_key()` method.
+///
+/// ```
+/// use bdk::bitcoin;
+/// use bdk::bitcoin::util::bip32;
+/// use bdk::keys::{DerivableKey, ExtendedKey, KeyError, ScriptContext};
+///
+/// struct MyCustomKeyType {
+///     key_data: bitcoin::PrivateKey,
+///     chain_code: Vec<u8>,
+///     network: bitcoin::Network,
+/// }
+///
+/// impl<Ctx: ScriptContext> DerivableKey<Ctx> for MyCustomKeyType {
+///     fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+///         let xprv = bip32::ExtendedPrivKey {
+///             network: self.network,
+///             depth: 0,
+///             parent_fingerprint: bip32::Fingerprint::default(),
+///             private_key: self.key_data,
+///             chain_code: bip32::ChainCode::from(self.chain_code.as_ref()),
+///             child_number: bip32::ChildNumber::Normal { index: 0 },
+///         };
+///
+///         xprv.into_extended_key()
+///     }
+/// }
+/// ```
+///
+/// Types that don't internally encode the [`Network`](bitcoin::Network) in which they are valid need some extra
+/// steps to override the set of valid networks, otherwise only the network specified in the
+/// [`ExtendedPrivKey`] or [`ExtendedPubKey`] will be considered valid.
+///
+/// ```
+/// use bdk::bitcoin;
+/// use bdk::bitcoin::util::bip32;
+/// use bdk::keys::{
+///     any_network, DerivableKey, DescriptorKey, ExtendedKey, KeyError, ScriptContext,
+/// };
+///
+/// struct MyCustomKeyType {
+///     key_data: bitcoin::PrivateKey,
+///     chain_code: Vec<u8>,
+/// }
+///
+/// impl<Ctx: ScriptContext> DerivableKey<Ctx> for MyCustomKeyType {
+///     fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+///         let xprv = bip32::ExtendedPrivKey {
+///             network: bitcoin::Network::Bitcoin, // pick an arbitrary network here
+///             depth: 0,
+///             parent_fingerprint: bip32::Fingerprint::default(),
+///             private_key: self.key_data,
+///             chain_code: bip32::ChainCode::from(self.chain_code.as_ref()),
+///             child_number: bip32::ChildNumber::Normal { index: 0 },
+///         };
+///
+///         xprv.into_extended_key()
+///     }
+///
+///     fn into_descriptor_key(
+///         self,
+///         source: Option<bip32::KeySource>,
+///         derivation_path: bip32::DerivationPath,
+///     ) -> Result<DescriptorKey<Ctx>, KeyError> {
+///         let descriptor_key = self
+///             .into_extended_key()?
+///             .into_descriptor_key(source, derivation_path)?;
+///
+///         // Override the set of valid networks here
+///         Ok(descriptor_key.override_valid_networks(any_network()))
+///     }
+/// }
+/// ```
+///
 /// [`DerivationPath`]: (bip32::DerivationPath)
-pub trait DerivableKey<Ctx: ScriptContext> {
-    /// Add a extra metadata, consume `self` and turn it into a [`DescriptorKey`]
-    fn add_metadata(
-        self,
-        origin: Option<bip32::KeySource>,
-        derivation_path: bip32::DerivationPath,
-    ) -> Result<DescriptorKey<Ctx>, KeyError>;
-}
+/// [`ExtendedPrivKey`]: (bip32::ExtendedPrivKey)
+/// [`ExtendedPubKey`]: (bip32::ExtendedPubKey)
+pub trait DerivableKey<Ctx: ScriptContext = miniscript::Legacy>: Sized {
+    /// Consume `self` and turn it into an [`ExtendedKey`]
+    ///
+    /// This can be used to get direct access to `xprv`s and `xpub`s for types that implement this trait,
+    /// like [`Mnemonic`](bip39::Mnemonic) when the `keys-bip39` feature is enabled.
+    #[cfg_attr(
+        feature = "keys-bip39",
+        doc = r##"
+```rust
+use bdk::bitcoin::Network;
+use bdk::keys::{DerivableKey, ExtendedKey};
+use bdk::keys::bip39::{Mnemonic, Language};
 
-impl<Ctx: ScriptContext> DerivableKey<Ctx> for bip32::ExtendedPubKey {
-    fn add_metadata(
+# fn main() -> Result<(), Box<dyn std::error::Error>> {
+let xkey: ExtendedKey =
+    Mnemonic::from_phrase(
+        "jelly crash boy whisper mouse ecology tuna soccer memory million news short",
+        Language::English
+    )?
+    .into_extended_key()?;
+let xprv = xkey.into_xprv(Network::Bitcoin).unwrap();
+# Ok(()) }
+```
+"##
+    )]
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError>;
+
+    /// Consume `self` and turn it into a [`DescriptorKey`] by adding the extra metadata, such as
+    /// key origin and derivation path
+    fn into_descriptor_key(
         self,
         origin: Option<bip32::KeySource>,
         derivation_path: bip32::DerivationPath,
     ) -> Result<DescriptorKey<Ctx>, KeyError> {
-        DescriptorPublicKey::XPub(DescriptorXKey {
-            origin,
-            xkey: self,
-            derivation_path,
-            is_wildcard: true,
-        })
-        .to_descriptor_key()
+        match self.into_extended_key()? {
+            ExtendedKey::Private((xprv, _)) => DescriptorSecretKey::XPrv(DescriptorXKey {
+                origin,
+                xkey: xprv,
+                derivation_path,
+                wildcard: Wildcard::Unhardened,
+            })
+            .into_descriptor_key(),
+            ExtendedKey::Public((xpub, _)) => DescriptorPublicKey::XPub(DescriptorXKey {
+                origin,
+                xkey: xpub,
+                derivation_path,
+                wildcard: Wildcard::Unhardened,
+            })
+            .into_descriptor_key(),
+        }
+    }
+}
+
+/// Identity conversion
+impl<Ctx: ScriptContext> DerivableKey<Ctx> for ExtendedKey<Ctx> {
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+        Ok(self)
+    }
+}
+
+impl<Ctx: ScriptContext> DerivableKey<Ctx> for bip32::ExtendedPubKey {
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+        Ok(self.into())
     }
 }
 
 impl<Ctx: ScriptContext> DerivableKey<Ctx> for bip32::ExtendedPrivKey {
-    fn add_metadata(
-        self,
-        origin: Option<bip32::KeySource>,
-        derivation_path: bip32::DerivationPath,
-    ) -> Result<DescriptorKey<Ctx>, KeyError> {
-        DescriptorSecretKey::XPrv(DescriptorXKey {
-            origin,
-            xkey: self,
-            derivation_path,
-            is_wildcard: true,
-        })
-        .to_descriptor_key()
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+        Ok(self.into())
     }
 }
 
@@ -389,37 +567,41 @@ where
     Ctx: ScriptContext,
     K: DerivableKey<Ctx>,
 {
-    fn add_metadata(
+    fn into_extended_key(self) -> Result<ExtendedKey<Ctx>, KeyError> {
+        self.key.into_extended_key()
+    }
+
+    fn into_descriptor_key(
         self,
         origin: Option<bip32::KeySource>,
         derivation_path: bip32::DerivationPath,
     ) -> Result<DescriptorKey<Ctx>, KeyError> {
-        let descriptor_key = self.key.add_metadata(origin, derivation_path)?;
+        let descriptor_key = self.key.into_descriptor_key(origin, derivation_path)?;
         Ok(descriptor_key.override_valid_networks(self.valid_networks))
     }
 }
 
 // Make generated keys directly usable in descriptors, and make sure they get assigned the right
 // `valid_networks`.
-impl<Ctx, K> ToDescriptorKey<Ctx> for GeneratedKey<K, Ctx>
+impl<Ctx, K> IntoDescriptorKey<Ctx> for GeneratedKey<K, Ctx>
 where
     Ctx: ScriptContext,
-    K: ToDescriptorKey<Ctx>,
+    K: IntoDescriptorKey<Ctx>,
 {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
-        let desc_key = self.key.to_descriptor_key()?;
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+        let desc_key = self.key.into_descriptor_key()?;
         Ok(desc_key.override_valid_networks(self.valid_networks))
     }
 }
 
 /// Trait for keys that can be generated
 ///
-/// The same rules about [`ScriptContext`] and [`ValidNetworks`] from [`ToDescriptorKey`] apply.
+/// The same rules about [`ScriptContext`] and [`ValidNetworks`] from [`IntoDescriptorKey`] apply.
 ///
 /// This trait is particularly useful when combined with [`DerivableKey`]: if `Self`
 /// implements it, the returned [`GeneratedKey`] will also implement it. The same is true for
-/// [`ToDescriptorKey`]: the generated keys can be directly used in descriptors if `Self` is also
-/// [`ToDescriptorKey`].
+/// [`IntoDescriptorKey`]: the generated keys can be directly used in descriptors if `Self` is also
+/// [`IntoDescriptorKey`].
 pub trait GeneratableKey<Ctx: ScriptContext>: Sized {
     /// Type specifying the amount of entropy required e.g. `[u8;32]`
     type Entropy: AsMut<[u8]> + Default;
@@ -529,27 +711,29 @@ impl<Ctx: ScriptContext> GeneratableKey<Ctx> for PrivateKey {
     }
 }
 
-impl<Ctx: ScriptContext, T: DerivableKey<Ctx>> ToDescriptorKey<Ctx> for (T, bip32::DerivationPath) {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
-        self.0.add_metadata(None, self.1)
+impl<Ctx: ScriptContext, T: DerivableKey<Ctx>> IntoDescriptorKey<Ctx>
+    for (T, bip32::DerivationPath)
+{
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+        self.0.into_descriptor_key(None, self.1)
     }
 }
 
-impl<Ctx: ScriptContext, T: DerivableKey<Ctx>> ToDescriptorKey<Ctx>
+impl<Ctx: ScriptContext, T: DerivableKey<Ctx>> IntoDescriptorKey<Ctx>
     for (T, bip32::KeySource, bip32::DerivationPath)
 {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
-        self.0.add_metadata(Some(self.1), self.2)
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+        self.0.into_descriptor_key(Some(self.1), self.2)
     }
 }
 
-fn expand_multi_keys<Pk: ToDescriptorKey<Ctx>, Ctx: ScriptContext>(
+fn expand_multi_keys<Pk: IntoDescriptorKey<Ctx>, Ctx: ScriptContext>(
     pks: Vec<Pk>,
     secp: &SecpCtx,
 ) -> Result<(Vec<DescriptorPublicKey>, KeyMap, ValidNetworks), KeyError> {
     let (pks, key_maps_networks): (Vec<_>, Vec<_>) = pks
         .into_iter()
-        .map(|key| Ok::<_, KeyError>(key.to_descriptor_key()?.extract(secp)?))
+        .map(|key| Ok::<_, KeyError>(key.into_descriptor_key()?.extract(secp)?))
         .collect::<Result<Vec<_>, _>>()?
         .into_iter()
         .map(|(a, b, c)| (a, (b, c)))
@@ -570,11 +754,11 @@ fn expand_multi_keys<Pk: ToDescriptorKey<Ctx>, Ctx: ScriptContext>(
 
 // Used internally by `bdk::fragment!` to build `pk_k()` fragments
 #[doc(hidden)]
-pub fn make_pk<Pk: ToDescriptorKey<Ctx>, Ctx: ScriptContext>(
+pub fn make_pk<Pk: IntoDescriptorKey<Ctx>, Ctx: ScriptContext>(
     descriptor_key: Pk,
     secp: &SecpCtx,
 ) -> Result<(Miniscript<DescriptorPublicKey, Ctx>, KeyMap, ValidNetworks), DescriptorError> {
-    let (key, key_map, valid_networks) = descriptor_key.to_descriptor_key()?.extract(secp)?;
+    let (key, key_map, valid_networks) = descriptor_key.into_descriptor_key()?.extract(secp)?;
     let minisc = Miniscript::from_ast(Terminal::PkK(key))?;
 
     minisc.check_minsicript()?;
@@ -584,7 +768,7 @@ pub fn make_pk<Pk: ToDescriptorKey<Ctx>, Ctx: ScriptContext>(
 
 // Used internally by `bdk::fragment!` to build `multi()` fragments
 #[doc(hidden)]
-pub fn make_multi<Pk: ToDescriptorKey<Ctx>, Ctx: ScriptContext>(
+pub fn make_multi<Pk: IntoDescriptorKey<Ctx>, Ctx: ScriptContext>(
     thresh: usize,
     pks: Vec<Pk>,
     secp: &SecpCtx,
@@ -599,35 +783,35 @@ pub fn make_multi<Pk: ToDescriptorKey<Ctx>, Ctx: ScriptContext>(
 
 // Used internally by `bdk::descriptor!` to build `sortedmulti()` fragments
 #[doc(hidden)]
-pub fn make_sortedmulti_inner<Pk: ToDescriptorKey<Ctx>, Ctx: ScriptContext>(
+pub fn make_sortedmulti<Pk, Ctx, F>(
     thresh: usize,
     pks: Vec<Pk>,
+    build_desc: F,
     secp: &SecpCtx,
-) -> Result<
-    (
-        SortedMultiVec<DescriptorPublicKey, Ctx>,
-        KeyMap,
-        ValidNetworks,
-    ),
-    DescriptorError,
-> {
+) -> Result<(Descriptor<DescriptorPublicKey>, KeyMap, ValidNetworks), DescriptorError>
+where
+    Pk: IntoDescriptorKey<Ctx>,
+    Ctx: ScriptContext,
+    F: Fn(
+        usize,
+        Vec<DescriptorPublicKey>,
+    ) -> Result<(Descriptor<DescriptorPublicKey>, PhantomData<Ctx>), DescriptorError>,
+{
     let (pks, key_map, valid_networks) = expand_multi_keys(pks, secp)?;
-    let minisc = SortedMultiVec::new(thresh, pks)?;
+    let descriptor = build_desc(thresh, pks)?.0;
 
-    // TODO: should we apply the checks here as well?
-
-    Ok((minisc, key_map, valid_networks))
+    Ok((descriptor, key_map, valid_networks))
 }
 
 /// The "identity" conversion is used internally by some `bdk::fragment`s
-impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for DescriptorKey<Ctx> {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+impl<Ctx: ScriptContext> IntoDescriptorKey<Ctx> for DescriptorKey<Ctx> {
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
         Ok(self)
     }
 }
 
-impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for DescriptorPublicKey {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+impl<Ctx: ScriptContext> IntoDescriptorKey<Ctx> for DescriptorPublicKey {
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
         let networks = match self {
             DescriptorPublicKey::SinglePub(_) => any_network(),
             DescriptorPublicKey::XPub(DescriptorXKey { xkey, .. })
@@ -642,18 +826,18 @@ impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for DescriptorPublicKey {
     }
 }
 
-impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for PublicKey {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+impl<Ctx: ScriptContext> IntoDescriptorKey<Ctx> for PublicKey {
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
         DescriptorPublicKey::SinglePub(DescriptorSinglePub {
             key: self,
             origin: None,
         })
-        .to_descriptor_key()
+        .into_descriptor_key()
     }
 }
 
-impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for DescriptorSecretKey {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+impl<Ctx: ScriptContext> IntoDescriptorKey<Ctx> for DescriptorSecretKey {
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
         let networks = match &self {
             DescriptorSecretKey::SinglePriv(sk) if sk.key.network == Network::Bitcoin => {
                 mainnet_network()
@@ -670,21 +854,21 @@ impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for DescriptorSecretKey {
     }
 }
 
-impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for &'_ str {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+impl<Ctx: ScriptContext> IntoDescriptorKey<Ctx> for &'_ str {
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
         DescriptorSecretKey::from_str(self)
             .map_err(|e| KeyError::Message(e.to_string()))?
-            .to_descriptor_key()
+            .into_descriptor_key()
     }
 }
 
-impl<Ctx: ScriptContext> ToDescriptorKey<Ctx> for PrivateKey {
-    fn to_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
+impl<Ctx: ScriptContext> IntoDescriptorKey<Ctx> for PrivateKey {
+    fn into_descriptor_key(self) -> Result<DescriptorKey<Ctx>, KeyError> {
         DescriptorSecretKey::SinglePriv(DescriptorSinglePriv {
             key: self,
             origin: None,
         })
-        .to_descriptor_key()
+        .into_descriptor_key()
     }
 }
 

src/lib.rs

@@ -56,7 +56,7 @@
 //! interact with the bitcoin P2P network.
 //!
 //! ```toml
-//! bdk = "0.2.0"
+//! bdk = "0.4.0"
 //! ```
 //!
 //! ## Sync the balance of a descriptor
@@ -115,7 +115,7 @@
 //! ### Example
 //! ```ignore
 //! use base64::decode;
-//! use bdk::{FeeRate, TxBuilder, Wallet};
+//! use bdk::{FeeRate, Wallet};
 //! use bdk::database::MemoryDatabase;
 //! use bdk::blockchain::{noop_progress, ElectrumBlockchain};
 //!
@@ -136,12 +136,12 @@
 //!     wallet.sync(noop_progress(), None)?;
 //!
 //!     let send_to = wallet.get_new_address()?;
-//!     let (psbt, details) = wallet.create_tx(
-//!         TxBuilder::with_recipients(vec![(send_to.script_pubkey(), 50_000)])
-//!             .enable_rbf()
-//!             .do_not_spend_change()
-//!             .fee_rate(FeeRate::from_sat_per_vb(5.0))
-//!     )?;
+//!     let (psbt, details) = wallet.build_tx()
+//!         .add_recipient(send_to.script_pubkey(), 50_000)
+//!         .enable_rbf()
+//!         .do_not_spend_change()
+//!         .fee_rate(FeeRate::from_sat_per_vb(5.0))
+//!         .finish()?;
 //!
 //!     println!("Transaction details: {:#?}", details);
 //!     println!("Unsigned PSBT: {}", base64::encode(&serialize(&psbt)));
@@ -210,6 +210,11 @@ extern crate serde;
 #[macro_use]
 extern crate serde_json;
 
+#[cfg(all(feature = "async-interface", feature = "electrum"))]
+compile_error!(
+    "Features async-interface and electrum are mutually exclusive and cannot be enabled together"
+);
+
 #[cfg(feature = "keys-bip39")]
 extern crate bip39;
 
@@ -265,3 +270,8 @@ pub use wallet::address_validator;
 pub use wallet::signer;
 pub use wallet::tx_builder::TxBuilder;
 pub use wallet::Wallet;
+
+/// Get the version of BDK at runtime
+pub fn version() -> &'static str {
+    env!("CARGO_PKG_VERSION", "unknown")
+}

src/wallet/address_validator.rs

@@ -45,6 +45,7 @@
 //! # use bdk::address_validator::*;
 //! # use bdk::database::*;
 //! # use bdk::*;
+//! #[derive(Debug)]
 //! struct PrintAddressAndContinue;
 //!
 //! impl AddressValidator for PrintAddressAndContinue {
@@ -111,7 +112,7 @@ impl std::error::Error for AddressValidatorError {}
 /// validator will be propagated up to the original caller that triggered the address generation.
 ///
 /// For a usage example see [this module](crate::address_validator)'s documentation.
-pub trait AddressValidator: Send + Sync {
+pub trait AddressValidator: Send + Sync + fmt::Debug {
     /// Validate or inspect an address
     fn validate(
         &self,
@@ -127,8 +128,8 @@ mod test {
 
     use super::*;
     use crate::wallet::test::{get_funded_wallet, get_test_wpkh};
-    use crate::wallet::TxBuilder;
 
+    #[derive(Debug)]
     struct TestValidator;
     impl AddressValidator for TestValidator {
         fn validate(
@@ -157,11 +158,8 @@ mod test {
         wallet.add_address_validator(Arc::new(TestValidator));
 
         let addr = testutils!(@external descriptors, 10);
-        wallet
-            .create_tx(TxBuilder::with_recipients(vec![(
-                addr.script_pubkey(),
-                25_000,
-            )]))
-            .unwrap();
+        let mut builder = wallet.build_tx();
+        builder.add_recipient(addr.script_pubkey(), 25_000);
+        builder.finish().unwrap();
     }
 }

src/wallet/coin_selection.rs

@@ -27,19 +27,16 @@
 //! This module provides the trait [`CoinSelectionAlgorithm`] that can be implemented to
 //! define custom coin selection algorithms.
 //!
-//! The coin selection algorithm is not globally part of a [`Wallet`](super::Wallet), instead it
-//! is selected whenever a [`Wallet::create_tx`](super::Wallet::create_tx) call is made, through
-//! the use of the [`TxBuilder`] structure, specifically with
-//! [`TxBuilder::coin_selection`](super::tx_builder::TxBuilder::coin_selection) method.
-//!
-//! The [`DefaultCoinSelectionAlgorithm`] selects the default coin selection algorithm that
-//! [`TxBuilder`] uses, if it's not explicitly overridden.
+//! You can specify a custom coin selection algorithm through the [`coin_selection`] method on
+//! [`TxBuilder`]. [`DefaultCoinSelectionAlgorithm`] aliases the coin selection algorithm that will
+//! be used if it is not explicitly set.
 //!
 //! [`TxBuilder`]: super::tx_builder::TxBuilder
+//! [`coin_selection`]: super::tx_builder::TxBuilder::coin_selection
 //!
 //! ## Example
 //!
-//! ```no_run
+//! ```
 //! # use std::str::FromStr;
 //! # use bitcoin::*;
 //! # use bdk::wallet::coin_selection::*;
@@ -84,14 +81,16 @@
 //!     }
 //! }
 //!
-//! # let wallet = Wallet::new_offline("", None, Network::Testnet, bdk::database::MemoryDatabase::default())?;
+//! # let wallet = doctest_wallet!();
 //! // create wallet, sync, ...
 //!
 //! let to_address = Address::from_str("2N4eQYCbKUHCCTUjBJeHcJp9ok6J2GZsTDt").unwrap();
-//! let (psbt, details) = wallet.create_tx(
-//!     TxBuilder::with_recipients(vec![(to_address.script_pubkey(), 50_000)])
-//!         .coin_selection(AlwaysSpendEverything),
-//! )?;
+//! let (psbt, details) = {
+//!     let mut builder = wallet.build_tx().coin_selection(AlwaysSpendEverything);
+//!     builder
+//!         .add_recipient(to_address.script_pubkey(), 50_000);
+//!     builder.finish()?
+//! };
 //!
 //! // inspect, sign, broadcast, ...
 //!

src/wallet/export.rs

@@ -76,6 +76,7 @@ use std::str::FromStr;
 
 use serde::{Deserialize, Serialize};
 
+use miniscript::descriptor::{ShInner, WshInner};
 use miniscript::{Descriptor, DescriptorPublicKey, ScriptContext, Terminal};
 
 use crate::database::BatchDatabase;
@@ -107,6 +108,10 @@ impl FromStr for WalletExport {
     }
 }
 
+fn remove_checksum(s: String) -> String {
+    s.splitn(2, '#').next().map(String::from).unwrap()
+}
+
 impl WalletExport {
     /// Export a wallet
     ///
@@ -127,6 +132,7 @@ impl WalletExport {
         let descriptor = wallet
             .descriptor
             .to_string_with_secret(&wallet.signers.as_key_map(wallet.secp_ctx()));
+        let descriptor = remove_checksum(descriptor);
         Self::is_compatible_with_core(&descriptor)?;
 
         let blockheight = match wallet.database.borrow().iter_txs(false) {
@@ -150,7 +156,9 @@ impl WalletExport {
         };
 
         let desc_to_string = |d: &Descriptor<DescriptorPublicKey>| {
-            d.to_string_with_secret(&wallet.change_signers.as_key_map(wallet.secp_ctx()))
+            let descriptor =
+                d.to_string_with_secret(&wallet.change_signers.as_key_map(wallet.secp_ctx()));
+            remove_checksum(descriptor)
         };
         if export.change_descriptor() != wallet.change_descriptor.as_ref().map(desc_to_string) {
             return Err("Incompatible change descriptor");
@@ -161,7 +169,7 @@ impl WalletExport {
 
     fn is_compatible_with_core(descriptor: &str) -> Result<(), &'static str> {
         fn check_ms<Ctx: ScriptContext>(
-            terminal: Terminal<String, Ctx>,
+            terminal: &Terminal<String, Ctx>,
         ) -> Result<(), &'static str> {
             if let Terminal::Multi(_, _) = terminal {
                 Ok(())
@@ -170,13 +178,22 @@ impl WalletExport {
             }
         }
 
+        // pkh(), wpkh(), sh(wpkh()) are always fine, as well as multi() and sortedmulti()
         match Descriptor::<String>::from_str(descriptor).map_err(|_| "Invalid descriptor")? {
-            Descriptor::Pk(_)
-            | Descriptor::Pkh(_)
-            | Descriptor::Wpkh(_)
-            | Descriptor::ShWpkh(_) => Ok(()),
-            Descriptor::Sh(ms) => check_ms(ms.node),
-            Descriptor::Wsh(ms) | Descriptor::ShWsh(ms) => check_ms(ms.node),
+            Descriptor::Pkh(_) | Descriptor::Wpkh(_) => Ok(()),
+            Descriptor::Sh(sh) => match sh.as_inner() {
+                ShInner::Wpkh(_) => Ok(()),
+                ShInner::SortedMulti(_) => Ok(()),
+                ShInner::Wsh(wsh) => match wsh.as_inner() {
+                    WshInner::SortedMulti(_) => Ok(()),
+                    WshInner::Ms(ms) => check_ms(&ms.node),
+                },
+                ShInner::Ms(ms) => check_ms(&ms.node),
+            },
+            Descriptor::Wsh(wsh) => match wsh.as_inner() {
+                WshInner::SortedMulti(_) => Ok(()),
+                WshInner::Ms(ms) => check_ms(&ms.node),
+            },
             _ => Err("The descriptor is not compatible with Bitcoin Core"),
         }
     }

src/wallet/signer.rs

@@ -33,7 +33,6 @@
 //! # use bitcoin::secp256k1::{Secp256k1, All};
 //! # use bitcoin::*;
 //! # use bitcoin::util::psbt;
-//! # use bitcoin::util::bip32::Fingerprint;
 //! # use bdk::signer::*;
 //! # use bdk::database::*;
 //! # use bdk::*;
@@ -46,6 +45,9 @@
 //! #     fn connect() -> Self {
 //! #         CustomHSM
 //! #     }
+//! #     fn get_id(&self) -> SignerId {
+//! #         SignerId::Dummy(0)
+//! #     }
 //! # }
 //! #[derive(Debug)]
 //! struct CustomSigner {
@@ -71,6 +73,10 @@
 //!         Ok(())
 //!     }
 //!
+//!     fn id(&self, _secp: &Secp256k1<All>) -> SignerId {
+//!         self.device.get_id()
+//!     }
+//!
 //!     fn sign_whole_tx(&self) -> bool {
 //!         false
 //!     }
@@ -82,7 +88,6 @@
 //! let mut wallet = Wallet::new_offline(descriptor, None, Network::Testnet, MemoryDatabase::default())?;
 //! wallet.add_signer(
 //!     KeychainKind::External,
-//!     Fingerprint::from_str("e30f11b8").unwrap().into(),
 //!     SignerOrdering(200),
 //!     Arc::new(custom_signer)
 //! );
@@ -118,6 +123,8 @@ pub enum SignerId {
     PkHash(hash160::Hash),
     /// The fingerprint of a BIP32 extended key
     Fingerprint(Fingerprint),
+    /// Dummy identifier
+    Dummy(u64),
 }
 
 impl From<hash160::Hash> for SignerId {
@@ -184,6 +191,12 @@ pub trait Signer: fmt::Debug + Send + Sync {
     /// input individually
     fn sign_whole_tx(&self) -> bool;
 
+    /// Return the [`SignerId`] for this signer
+    ///
+    /// The [`SignerId`] can be used to lookup a signer in the [`Wallet`](crate::Wallet)'s signers map or to
+    /// compare two signers.
+    fn id(&self, secp: &SecpCtx) -> SignerId;
+
     /// Return the secret key for the signer
     ///
     /// This is used internally to reconstruct the original descriptor that may contain secrets.
@@ -207,7 +220,7 @@ impl Signer for DescriptorXKey<ExtendedPrivKey> {
         }
 
         let (public_key, deriv_path) = match psbt.inputs[input_index]
-            .hd_keypaths
+            .bip32_derivation
             .iter()
             .filter_map(|(pk, &(fingerprint, ref path))| {
                 if self.matches(&(fingerprint, path.clone()), &secp).is_some() {
@@ -234,6 +247,10 @@ impl Signer for DescriptorXKey<ExtendedPrivKey> {
         false
     }
 
+    fn id(&self, secp: &SecpCtx) -> SignerId {
+        SignerId::from(self.root_fingerprint(&secp))
+    }
+
     fn descriptor_secret_key(&self) -> Option<DescriptorSecretKey> {
         Some(DescriptorSecretKey::XPrv(self.clone()))
     }
@@ -285,6 +302,10 @@ impl Signer for PrivateKey {
         false
     }
 
+    fn id(&self, secp: &SecpCtx) -> SignerId {
+        SignerId::from(self.public_key(secp).to_pubkeyhash())
+    }
+
     fn descriptor_secret_key(&self) -> Option<DescriptorSecretKey> {
         Some(DescriptorSecretKey::SinglePriv(DescriptorSinglePriv {
             key: *self,
@@ -345,12 +366,7 @@ impl From<KeyMap> for SignersContainer {
         for (_, secret) in keymap {
             match secret {
                 DescriptorSecretKey::SinglePriv(private_key) => container.add_external(
-                    SignerId::from(
-                        private_key
-                            .key
-                            .public_key(&Secp256k1::signing_only())
-                            .to_pubkeyhash(),
-                    ),
+                    SignerId::from(private_key.key.public_key(&secp).to_pubkeyhash()),
                     SignerOrdering::default(),
                     Arc::new(private_key.key),
                 ),
@@ -544,9 +560,9 @@ impl Eq for SignersContainerKey {}
 mod signers_container_tests {
     use super::*;
     use crate::descriptor;
-    use crate::descriptor::ToWalletDescriptor;
-    use crate::keys::{DescriptorKey, ToDescriptorKey};
-    use bitcoin::secp256k1::All;
+    use crate::descriptor::IntoWalletDescriptor;
+    use crate::keys::{DescriptorKey, IntoDescriptorKey};
+    use bitcoin::secp256k1::{All, Secp256k1};
     use bitcoin::util::bip32;
     use bitcoin::util::psbt::PartiallySignedTransaction;
     use bitcoin::Network;
@@ -558,10 +574,14 @@ mod signers_container_tests {
     // This happens usually when a set of signers is created from a descriptor with private keys.
     #[test]
     fn signers_with_same_ordering() {
+        let secp = Secp256k1::new();
+
         let (prvkey1, _, _) = setup_keys(TPRV0_STR);
         let (prvkey2, _, _) = setup_keys(TPRV1_STR);
         let desc = descriptor!(sh(multi(2, prvkey1, prvkey2))).unwrap();
-        let (_, keymap) = desc.to_wallet_descriptor(Network::Testnet).unwrap();
+        let (_, keymap) = desc
+            .into_wallet_descriptor(&secp, Network::Testnet)
+            .unwrap();
 
         let signers = SignersContainer::from(keymap);
         assert_eq!(signers.ids().len(), 2);
@@ -650,6 +670,10 @@ mod signers_container_tests {
             Ok(())
         }
 
+        fn id(&self, _secp: &SecpCtx) -> SignerId {
+            SignerId::Dummy(42)
+        }
+
         fn sign_whole_tx(&self) -> bool {
             true
         }
@@ -668,8 +692,8 @@ mod signers_container_tests {
         let tprv = bip32::ExtendedPrivKey::from_str(tprv).unwrap();
         let tpub = bip32::ExtendedPubKey::from_private(&secp, &tprv);
         let fingerprint = tprv.fingerprint(&secp);
-        let prvkey = (tprv, path.clone()).to_descriptor_key().unwrap();
-        let pubkey = (tpub, path).to_descriptor_key().unwrap();
+        let prvkey = (tprv, path.clone()).into_descriptor_key().unwrap();
+        let pubkey = (tpub, path).into_descriptor_key().unwrap();
 
         (prvkey, pubkey, fingerprint)
     }

src/wallet/tx_builder.rs

@@ -32,14 +32,21 @@
 //! # use bdk::*;
 //! # use bdk::wallet::tx_builder::CreateTx;
 //! # let to_address = Address::from_str("2N4eQYCbKUHCCTUjBJeHcJp9ok6J2GZsTDt").unwrap();
-//! // Create a transaction with one output to `to_address` of 50_000 satoshi, with a custom fee rate
-//! // of 5.0 satoshi/vbyte, only spending non-change outputs and with RBF signaling
-//! // enabled
-//! let builder = TxBuilder::with_recipients(vec![(to_address.script_pubkey(), 50_000)])
+//! # let wallet = doctest_wallet!();
+//! // create a TxBuilder from a wallet
+//! let mut tx_builder = wallet.build_tx();
+//!
+//! tx_builder
+//!     // Create a transaction with one output to `to_address` of 50_000 satoshi
+//!     .add_recipient(to_address.script_pubkey(), 50_000)
+//!     // With a custom fee rate of 5.0 satoshi/vbyte
 //!     .fee_rate(FeeRate::from_sat_per_vb(5.0))
+//!     // Only spend non-change outputs
 //!     .do_not_spend_change()
+//!     // Turn on RBF signaling
 //!     .enable_rbf();
-//! # let builder: TxBuilder<bdk::database::MemoryDatabase, _, CreateTx> = builder;
+//! let (psbt, tx_details) = tx_builder.finish()?;
+//! # Ok::<(), bdk::Error>(())
 //! ```
 
 use std::collections::BTreeMap;
@@ -47,39 +54,103 @@ use std::collections::HashSet;
 use std::default::Default;
 use std::marker::PhantomData;
 
+use bitcoin::util::psbt::PartiallySignedTransaction as PSBT;
 use bitcoin::{OutPoint, Script, SigHashType, Transaction};
 
-use super::coin_selection::{CoinSelectionAlgorithm, DefaultCoinSelectionAlgorithm};
-use crate::database::Database;
-use crate::types::{FeeRate, KeychainKind, UTXO};
+use miniscript::descriptor::DescriptorTrait;
 
+use super::coin_selection::{CoinSelectionAlgorithm, DefaultCoinSelectionAlgorithm};
+use crate::{database::BatchDatabase, Error, Wallet};
+use crate::{
+    types::{FeeRate, KeychainKind, UTXO},
+    TransactionDetails,
+};
 /// Context in which the [`TxBuilder`] is valid
 pub trait TxBuilderContext: std::fmt::Debug + Default + Clone {}
 
-/// [`Wallet::create_tx`](super::Wallet::create_tx) context
+/// Marker type to indicate the [`TxBuilder`] is being used to create a new transaction (as opposed
+/// to bumping the fee of an existing one).
 #[derive(Debug, Default, Clone)]
 pub struct CreateTx;
 impl TxBuilderContext for CreateTx {}
 
-/// [`Wallet::bump_fee`](super::Wallet::bump_fee) context
+/// Marker type to indicate the [`TxBuilder`] is being used to bump the fee of an existing transaction.
 #[derive(Debug, Default, Clone)]
 pub struct BumpFee;
 impl TxBuilderContext for BumpFee {}
 
 /// A transaction builder
 ///
-/// This structure contains the configuration that the wallet must follow to build a transaction.
+/// A `TxBuilder` is created by calling [`build_tx`] or [`build_fee_bump`] on a wallet. After
+/// assigning it, you set options on it until finally calling [`finish`] to consume the builder and
+/// generate the transaction.
 ///
-/// For an example see [this module](super::tx_builder)'s documentation;
-#[derive(Debug)]
-pub struct TxBuilder<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> {
+/// Each option setting method on `TxBuilder` takes and returns `&mut self` so you can chain calls
+/// as in the following example:
+///
+/// ```
+/// # use bdk::*;
+/// # use bdk::wallet::tx_builder::*;
+/// # use bitcoin::*;
+/// # use core::str::FromStr;
+/// # let wallet = doctest_wallet!();
+/// # let addr1 = Address::from_str("2N4eQYCbKUHCCTUjBJeHcJp9ok6J2GZsTDt").unwrap();
+/// # let addr2 = addr1.clone();
+/// // chaining
+/// let (psbt1, details) = {
+///     let mut builder = wallet.build_tx();
+///     builder
+///        .ordering(TxOrdering::Untouched)
+///        .add_recipient(addr1.script_pubkey(), 50_000)
+///        .add_recipient(addr2.script_pubkey(), 50_000);
+///     builder.finish()?
+/// };
+///
+/// // non-chaining
+/// let (psbt2, details) = {
+///     let mut builder = wallet.build_tx();
+///     builder.ordering(TxOrdering::Untouched);
+///     for addr in &[addr1, addr2] {
+///         builder.add_recipient(addr.script_pubkey(), 50_000);
+///     }
+///     builder.finish()?
+/// };
+///
+/// assert_eq!(psbt1.global.unsigned_tx.output[..2], psbt2.global.unsigned_tx.output[..2]);
+/// # Ok::<(), bdk::Error>(())
+/// ```
+///
+/// At the moment [`coin_selection`] is an exception to the rule as it consumes `self`.
+/// This means it is usually best to call [`coin_selection`] on the return value of `build_tx` before assigning it.
+///
+/// For further examples see [this module](super::tx_builder)'s documentation;
+///
+/// [`build_tx`]: Wallet::build_tx
+/// [`build_fee_bump`]: Wallet::build_fee_bump
+/// [`finish`]: Self::finish
+/// [`coin_selection`]: Self::coin_selection
+#[derive(Clone, Debug)]
+pub struct TxBuilder<'a, B, D, Cs, Ctx> {
+    pub(crate) wallet: &'a Wallet<B, D>,
+    // params and coin_selection are Options not becasue they are optionally set (they are always
+    // there) but because `.finish()` uses `Option::take` to get an owned value from a &mut self.
+    // They are only `None` after `.finish()` is called.
+    pub(crate) params: TxParams,
+    pub(crate) coin_selection: Cs,
+    pub(crate) phantom: PhantomData<Ctx>,
+}
+
+/// The parameters for transaction creation sans coin selection algorithm.
+//TODO: TxParams should eventually be exposed publicly.
+#[derive(Default, Debug, Clone)]
+pub(crate) struct TxParams {
     pub(crate) recipients: Vec<(Script, u64)>,
     pub(crate) drain_wallet: bool,
     pub(crate) single_recipient: Option<Script>,
     pub(crate) fee_policy: Option<FeePolicy>,
     pub(crate) internal_policy_path: Option<BTreeMap<String, Vec<usize>>>,
     pub(crate) external_policy_path: Option<BTreeMap<String, Vec<usize>>>,
-    pub(crate) utxos: Vec<OutPoint>,
+    pub(crate) utxos: Vec<(UTXO, usize)>,
     pub(crate) unspendable: HashSet<OutPoint>,
     pub(crate) manually_selected_only: bool,
     pub(crate) sighash: Option<SigHashType>,
@@ -90,13 +161,17 @@ pub struct TxBuilder<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderC
     pub(crate) change_policy: ChangeSpendPolicy,
     pub(crate) force_non_witness_utxo: bool,
     pub(crate) add_global_xpubs: bool,
-    pub(crate) coin_selection: Cs,
     pub(crate) include_output_redeem_witness_script: bool,
-
-    phantom: PhantomData<(D, Ctx)>,
+    pub(crate) bumping_fee: Option<PreviousFee>,
 }
 
-#[derive(Debug)]
+#[derive(Clone, Copy, Debug)]
+pub(crate) struct PreviousFee {
+    pub absolute: u64,
+    pub rate: f32,
+}
+
+#[derive(Debug, Clone, Copy)]
 pub(crate) enum FeePolicy {
     FeeRate(FeeRate),
     FeeAmount(u64),
@@ -108,58 +183,19 @@ impl std::default::Default for FeePolicy {
     }
 }
 
-// Unfortunately derive doesn't work with `PhantomData`: https://github.com/rust-lang/rust/issues/26925
-impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> Default
-    for TxBuilder<D, Cs, Ctx>
-where
-    Cs: Default,
-{
-    fn default() -> Self {
-        TxBuilder {
-            recipients: Default::default(),
-            drain_wallet: Default::default(),
-            single_recipient: Default::default(),
-            fee_policy: Default::default(),
-            internal_policy_path: Default::default(),
-            external_policy_path: Default::default(),
-            utxos: Default::default(),
-            unspendable: Default::default(),
-            manually_selected_only: Default::default(),
-            sighash: Default::default(),
-            ordering: Default::default(),
-            locktime: Default::default(),
-            rbf: Default::default(),
-            version: Default::default(),
-            change_policy: Default::default(),
-            force_non_witness_utxo: Default::default(),
-            add_global_xpubs: Default::default(),
-            coin_selection: Default::default(),
-            include_output_redeem_witness_script: Default::default(),
-
-            phantom: PhantomData,
-        }
-    }
-}
-
-// methods supported by both contexts, but only for `DefaultCoinSelectionAlgorithm`
-impl<D: Database, Ctx: TxBuilderContext> TxBuilder<D, DefaultCoinSelectionAlgorithm, Ctx> {
-    /// Create an empty builder
-    pub fn new() -> Self {
-        Self::default()
-    }
-}
-
 // methods supported by both contexts, for any CoinSelectionAlgorithm
-impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> TxBuilder<D, Cs, Ctx> {
+impl<'a, B, D: BatchDatabase, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext>
+    TxBuilder<'a, B, D, Cs, Ctx>
+{
     /// Set a custom fee rate
-    pub fn fee_rate(mut self, fee_rate: FeeRate) -> Self {
-        self.fee_policy = Some(FeePolicy::FeeRate(fee_rate));
+    pub fn fee_rate(&mut self, fee_rate: FeeRate) -> &mut Self {
+        self.params.fee_policy = Some(FeePolicy::FeeRate(fee_rate));
         self
     }
 
     /// Set an absolute fee
-    pub fn fee_absolute(mut self, fee_amount: u64) -> Self {
-        self.fee_policy = Some(FeePolicy::FeeAmount(fee_amount));
+    pub fn fee_absolute(&mut self, fee_amount: u64) -> &mut Self {
+        self.params.fee_policy = Some(FeePolicy::FeeAmount(fee_amount));
         self
     }
 
@@ -211,96 +247,107 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> TxBuilde
     /// # use bitcoin::*;
     /// # use bdk::*;
     /// # let to_address = Address::from_str("2N4eQYCbKUHCCTUjBJeHcJp9ok6J2GZsTDt").unwrap();
+    /// # let wallet = doctest_wallet!();
     /// let mut path = BTreeMap::new();
     /// path.insert("aabbccdd".to_string(), vec![0, 1]);
     ///
-    /// let builder = TxBuilder::with_recipients(vec![(to_address.script_pubkey(), 50_000)])
+    /// let builder = wallet.build_tx()
+    ///     .add_recipient(to_address.script_pubkey(), 50_000)
     ///     .policy_path(path, KeychainKind::External);
-    /// # let builder: TxBuilder<bdk::database::MemoryDatabase, _, _> = builder;
+    ///
+    /// # Ok::<(), bdk::Error>(())
     /// ```
     pub fn policy_path(
-        mut self,
+        &mut self,
         policy_path: BTreeMap<String, Vec<usize>>,
         keychain: KeychainKind,
-    ) -> Self {
+    ) -> &mut Self {
         let to_update = match keychain {
-            KeychainKind::Internal => &mut self.internal_policy_path,
-            KeychainKind::External => &mut self.external_policy_path,
+            KeychainKind::Internal => &mut self.params.internal_policy_path,
+            KeychainKind::External => &mut self.params.external_policy_path,
         };
 
         *to_update = Some(policy_path);
         self
     }
 
-    /// Replace the internal list of utxos that **must** be spent with a new list
+    /// Add the list of outpoints to the internal list of UTXOs that **must** be spent.
+    ///
+    /// If an error occurs while adding any of the UTXOs then none of them are added and the error is returned.
     ///
     /// These have priority over the "unspendable" utxos, meaning that if a utxo is present both in
     /// the "utxos" and the "unspendable" list, it will be spent.
-    pub fn utxos(mut self, utxos: Vec<OutPoint>) -> Self {
-        self.utxos = utxos;
-        self
+    pub fn add_utxos(&mut self, outpoints: &[OutPoint]) -> Result<&mut Self, Error> {
+        let utxos = outpoints
+            .iter()
+            .map(|outpoint| self.wallet.get_utxo(*outpoint)?.ok_or(Error::UnknownUTXO))
+            .collect::<Result<Vec<_>, _>>()?;
+
+        for utxo in utxos {
+            let descriptor = self.wallet.get_descriptor_for_keychain(utxo.keychain);
+            let satisfaction_weight = descriptor.max_satisfaction_weight().unwrap();
+            self.params.utxos.push((utxo, satisfaction_weight));
+        }
+
+        Ok(self)
     }
 
     /// Add a utxo to the internal list of utxos that **must** be spent
     ///
     /// These have priority over the "unspendable" utxos, meaning that if a utxo is present both in
     /// the "utxos" and the "unspendable" list, it will be spent.
-    pub fn add_utxo(mut self, utxo: OutPoint) -> Self {
-        self.utxos.push(utxo);
-        self
+    pub fn add_utxo(&mut self, outpoint: OutPoint) -> Result<&mut Self, Error> {
+        self.add_utxos(&[outpoint])
     }
 
-    /// Only spend utxos added by [`add_utxo`] and [`utxos`].
+    /// Only spend utxos added by [`add_utxo`].
     ///
     /// The wallet will **not** add additional utxos to the transaction even if they are needed to
     /// make the transaction valid.
     ///
     /// [`add_utxo`]: Self::add_utxo
-    /// [`utxos`]: Self::utxos
-    pub fn manually_selected_only(mut self) -> Self {
-        self.manually_selected_only = true;
+    pub fn manually_selected_only(&mut self) -> &mut Self {
+        self.params.manually_selected_only = true;
         self
     }
 
     /// Replace the internal list of unspendable utxos with a new list
     ///
-    /// It's important to note that the "must-be-spent" utxos added with [`TxBuilder::utxos`] and
-    /// [`TxBuilder::add_utxo`] have priority over these. See the docs of the two linked methods
-    /// for more details.
-    pub fn unspendable(mut self, unspendable: Vec<OutPoint>) -> Self {
-        self.unspendable = unspendable.into_iter().collect();
+    /// It's important to note that the "must-be-spent" utxos added with [`TxBuilder::add_utxo`]
+    /// have priority over these. See the docs of the two linked methods for more details.
+    pub fn unspendable(&mut self, unspendable: Vec<OutPoint>) -> &mut Self {
+        self.params.unspendable = unspendable.into_iter().collect();
         self
     }
 
     /// Add a utxo to the internal list of unspendable utxos
     ///
-    /// It's important to note that the "must-be-spent" utxos added with [`TxBuilder::utxos`] and
-    /// [`TxBuilder::add_utxo`] have priority over this. See the docs of the two linked methods
-    /// for more details.
-    pub fn add_unspendable(mut self, unspendable: OutPoint) -> Self {
-        self.unspendable.insert(unspendable);
+    /// It's important to note that the "must-be-spent" utxos added with [`TxBuilder::add_utxo`]
+    /// have priority over this. See the docs of the two linked methods for more details.
+    pub fn add_unspendable(&mut self, unspendable: OutPoint) -> &mut Self {
+        self.params.unspendable.insert(unspendable);
         self
     }
 
     /// Sign with a specific sig hash
     ///
     /// **Use this option very carefully**
-    pub fn sighash(mut self, sighash: SigHashType) -> Self {
-        self.sighash = Some(sighash);
+    pub fn sighash(&mut self, sighash: SigHashType) -> &mut Self {
+        self.params.sighash = Some(sighash);
         self
     }
 
     /// Choose the ordering for inputs and outputs of the transaction
-    pub fn ordering(mut self, ordering: TxOrdering) -> Self {
-        self.ordering = ordering;
+    pub fn ordering(&mut self, ordering: TxOrdering) -> &mut Self {
+        self.params.ordering = ordering;
         self
     }
 
     /// Use a specific nLockTime while creating the transaction
     ///
     /// This can cause conflicts if the wallet's descriptors contain an "after" (OP_CLTV) operator.
-    pub fn nlocktime(mut self, locktime: u32) -> Self {
-        self.locktime = Some(locktime);
+    pub fn nlocktime(&mut self, locktime: u32) -> &mut Self {
+        self.params.locktime = Some(locktime);
         self
     }
 
@@ -308,8 +355,8 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> TxBuilde
     ///
     /// The `version` should always be greater than `0` and greater than `1` if the wallet's
     /// descriptors contain an "older" (OP_CSV) operator.
-    pub fn version(mut self, version: i32) -> Self {
-        self.version = Some(Version(version));
+    pub fn version(&mut self, version: i32) -> &mut Self {
+        self.params.version = Some(Version(version));
         self
     }
 
@@ -317,8 +364,8 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> TxBuilde
     ///
     /// This effectively adds all the change outputs to the "unspendable" list. See
     /// [`TxBuilder::unspendable`].
-    pub fn do_not_spend_change(mut self) -> Self {
-        self.change_policy = ChangeSpendPolicy::ChangeForbidden;
+    pub fn do_not_spend_change(&mut self) -> &mut Self {
+        self.params.change_policy = ChangeSpendPolicy::ChangeForbidden;
         self
     }
 
@@ -326,15 +373,15 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> TxBuilde
     ///
     /// This effectively adds all the non-change outputs to the "unspendable" list. See
     /// [`TxBuilder::unspendable`].
-    pub fn only_spend_change(mut self) -> Self {
-        self.change_policy = ChangeSpendPolicy::OnlyChange;
+    pub fn only_spend_change(&mut self) -> &mut Self {
+        self.params.change_policy = ChangeSpendPolicy::OnlyChange;
         self
     }
 
     /// Set a specific [`ChangeSpendPolicy`]. See [`TxBuilder::do_not_spend_change`] and
     /// [`TxBuilder::only_spend_change`] for some shortcuts.
-    pub fn change_policy(mut self, change_policy: ChangeSpendPolicy) -> Self {
-        self.change_policy = change_policy;
+    pub fn change_policy(&mut self, change_policy: ChangeSpendPolicy) -> &mut Self {
+        self.params.change_policy = change_policy;
         self
     }
 
@@ -342,8 +389,8 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> TxBuilde
     /// descriptors.
     ///
     /// This is useful for signers which always require it, like Trezor hardware wallets.
-    pub fn force_non_witness_utxo(mut self) -> Self {
-        self.force_non_witness_utxo = true;
+    pub fn force_non_witness_utxo(&mut self) -> &mut Self {
+        self.params.force_non_witness_utxo = true;
         self
     }
 
@@ -351,8 +398,8 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> TxBuilde
     /// [`psbt::Output::witness_script`](bitcoin::util::psbt::Output::witness_script) fields.
     ///
     /// This is useful for signers which always require it, like ColdCard hardware wallets.
-    pub fn include_output_redeem_witness_script(mut self) -> Self {
-        self.include_output_redeem_witness_script = true;
+    pub fn include_output_redeem_witness_script(&mut self) -> &mut Self {
+        self.params.include_output_redeem_witness_script = true;
         self
     }
 
@@ -361,69 +408,54 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>, Ctx: TxBuilderContext> TxBuilde
     ///
     /// This is useful for offline signers that take part to a multisig. Some hardware wallets like
     /// BitBox and ColdCard are known to require this.
-    pub fn add_global_xpubs(mut self) -> Self {
-        self.add_global_xpubs = true;
+    pub fn add_global_xpubs(&mut self) -> &mut Self {
+        self.params.add_global_xpubs = true;
         self
     }
 
     /// Spend all the available inputs. This respects filters like [`TxBuilder::unspendable`] and the change policy.
-    pub fn drain_wallet(mut self) -> Self {
-        self.drain_wallet = true;
+    pub fn drain_wallet(&mut self) -> &mut Self {
+        self.params.drain_wallet = true;
         self
     }
 
     /// Choose the coin selection algorithm
     ///
     /// Overrides the [`DefaultCoinSelectionAlgorithm`](super::coin_selection::DefaultCoinSelectionAlgorithm).
+    ///
+    /// Note that this function consumes the builder and returns it so it is usually best to put this as the first call on the builder.
     pub fn coin_selection<P: CoinSelectionAlgorithm<D>>(
         self,
         coin_selection: P,
-    ) -> TxBuilder<D, P, Ctx> {
+    ) -> TxBuilder<'a, B, D, P, Ctx> {
         TxBuilder {
-            recipients: self.recipients,
-            drain_wallet: self.drain_wallet,
-            single_recipient: self.single_recipient,
-            fee_policy: self.fee_policy,
-            internal_policy_path: self.internal_policy_path,
-            external_policy_path: self.external_policy_path,
-            utxos: self.utxos,
-            unspendable: self.unspendable,
-            manually_selected_only: self.manually_selected_only,
-            sighash: self.sighash,
-            ordering: self.ordering,
-            locktime: self.locktime,
-            rbf: self.rbf,
-            version: self.version,
-            change_policy: self.change_policy,
-            force_non_witness_utxo: self.force_non_witness_utxo,
-            add_global_xpubs: self.add_global_xpubs,
-            include_output_redeem_witness_script: self.include_output_redeem_witness_script,
+            wallet: self.wallet,
+            params: self.params,
             coin_selection,
-
             phantom: PhantomData,
         }
     }
-}
 
-// methods supported only by create_tx, and only for `DefaultCoinSelectionAlgorithm`
-impl<D: Database> TxBuilder<D, DefaultCoinSelectionAlgorithm, CreateTx> {
-    /// Create a builder starting from a list of recipients
-    pub fn with_recipients(recipients: Vec<(Script, u64)>) -> Self {
-        Self::default().set_recipients(recipients)
+    /// Finish the building the transaction.
+    ///
+    /// Returns the [`BIP174`] "PSBT" and summary details about the transaction.
+    ///
+    /// [`BIP174`]: https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki
+    pub fn finish(self) -> Result<(PSBT, TransactionDetails), Error> {
+        self.wallet.create_tx(self.coin_selection, self.params)
     }
 }
 
-// methods supported only by create_tx, for any `CoinSelectionAlgorithm`
-impl<D: Database, Cs: CoinSelectionAlgorithm<D>> TxBuilder<D, Cs, CreateTx> {
+impl<'a, B, D: BatchDatabase, Cs: CoinSelectionAlgorithm<D>> TxBuilder<'a, B, D, Cs, CreateTx> {
     /// Replace the recipients already added with a new list
-    pub fn set_recipients(mut self, recipients: Vec<(Script, u64)>) -> Self {
-        self.recipients = recipients;
+    pub fn set_recipients(&mut self, recipients: Vec<(Script, u64)>) -> &mut Self {
+        self.params.recipients = recipients;
         self
     }
 
     /// Add a recipient to the internal list
-    pub fn add_recipient(mut self, script_pubkey: Script, amount: u64) -> Self {
-        self.recipients.push((script_pubkey, amount));
+    pub fn add_recipient(&mut self, script_pubkey: Script, amount: u64) -> &mut Self {
+        self.params.recipients.push((script_pubkey, amount));
         self
     }
 
@@ -436,14 +468,14 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>> TxBuilder<D, Cs, CreateTx> {
     /// It can only be used in conjunction with [`drain_wallet`](Self::drain_wallet) to send the
     /// entire content of the wallet (minus filters) to a single recipient or with a
     /// list of manually selected UTXOs by enabling [`manually_selected_only`](Self::manually_selected_only)
-    /// and selecting them with [`utxos`](Self::utxos) or [`add_utxo`](Self::add_utxo).
+    /// and selecting them with or [`add_utxo`](Self::add_utxo).
     ///
     /// When bumping the fees of a transaction made with this option, the user should remeber to
     /// add [`maintain_single_recipient`](Self::maintain_single_recipient) to correctly update the
     /// single output instead of adding one more for the change.
-    pub fn set_single_recipient(mut self, recipient: Script) -> Self {
-        self.single_recipient = Some(recipient);
-        self.recipients.clear();
+    pub fn set_single_recipient(&mut self, recipient: Script) -> &mut Self {
+        self.params.single_recipient = Some(recipient);
+        self.params.recipients.clear();
 
         self
     }
@@ -451,8 +483,8 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>> TxBuilder<D, Cs, CreateTx> {
     /// Enable signaling RBF
     ///
     /// This will use the default nSequence value of `0xFFFFFFFD`.
-    pub fn enable_rbf(mut self) -> Self {
-        self.rbf = Some(RBFValue::Default);
+    pub fn enable_rbf(&mut self) -> &mut Self {
+        self.params.rbf = Some(RBFValue::Default);
         self
     }
 
@@ -463,17 +495,17 @@ impl<D: Database, Cs: CoinSelectionAlgorithm<D>> TxBuilder<D, Cs, CreateTx> {
     ///
     /// If the `nsequence` is higher than `0xFFFFFFFD` an error will be thrown, since it would not
     /// be a valid nSequence to signal RBF.
-    pub fn enable_rbf_with_sequence(mut self, nsequence: u32) -> Self {
-        self.rbf = Some(RBFValue::Value(nsequence));
+    pub fn enable_rbf_with_sequence(&mut self, nsequence: u32) -> &mut Self {
+        self.params.rbf = Some(RBFValue::Value(nsequence));
         self
     }
 }
 
 // methods supported only by bump_fee
-impl<D: Database> TxBuilder<D, DefaultCoinSelectionAlgorithm, BumpFee> {
+impl<'a, B, D: BatchDatabase> TxBuilder<'a, B, D, DefaultCoinSelectionAlgorithm, BumpFee> {
     /// Bump the fees of a transaction made with [`set_single_recipient`](Self::set_single_recipient)
     ///
-    /// Unless extra inputs are specified with [`add_utxo`] or [`utxos`], this flag will make
+    /// Unless extra inputs are specified with [`add_utxo`], this flag will make
     /// `bump_fee` reduce the value of the existing output, or fail if it would be consumed
     /// entirely given the higher new fee rate.
     ///
@@ -483,10 +515,13 @@ impl<D: Database> TxBuilder<D, DefaultCoinSelectionAlgorithm, BumpFee> {
     /// Fails if the transaction has more than one outputs.
     ///
     /// [`add_utxo`]: Self::add_utxo
-    /// [`utxos`]: Self::utxos
-    pub fn maintain_single_recipient(mut self) -> Self {
-        self.single_recipient = Some(Script::default());
-        self
+    pub fn maintain_single_recipient(&mut self) -> Result<&mut Self, Error> {
+        let mut recipients = self.params.recipients.drain(..).collect::<Vec<_>>();
+        if recipients.len() != 1 {
+            return Err(Error::SingleRecipientMultipleOutputs);
+        }
+        self.params.single_recipient = Some(recipients.pop().unwrap().0);
+        Ok(self)
     }
 }
 

src/wallet/utils.rs

@@ -23,9 +23,7 @@
 // SOFTWARE.
 
 use bitcoin::secp256k1::{All, Secp256k1};
-use bitcoin::util::bip32;
 
-use miniscript::descriptor::DescriptorPublicKeyCtx;
 use miniscript::{MiniscriptKey, Satisfier, ToPublicKey};
 
 // De-facto standard "dust limit" (even though it should change based on the output type)
@@ -110,7 +108,7 @@ pub(crate) fn check_nlocktime(nlocktime: u32, required: u32) -> bool {
     true
 }
 
-impl<ToPkCtx: Copy, Pk: MiniscriptKey + ToPublicKey<ToPkCtx>> Satisfier<ToPkCtx, Pk> for After {
+impl<Pk: MiniscriptKey + ToPublicKey> Satisfier<Pk> for After {
     fn check_after(&self, n: u32) -> bool {
         if let Some(current_height) = self.current_height {
             current_height >= n
@@ -140,7 +138,7 @@ impl Older {
     }
 }
 
-impl<ToPkCtx: Copy, Pk: MiniscriptKey + ToPublicKey<ToPkCtx>> Satisfier<ToPkCtx, Pk> for Older {
+impl<Pk: MiniscriptKey + ToPublicKey> Satisfier<Pk> for Older {
     fn check_older(&self, n: u32) -> bool {
         if let Some(current_height) = self.current_height {
             // TODO: test >= / >
@@ -152,12 +150,6 @@ impl<ToPkCtx: Copy, Pk: MiniscriptKey + ToPublicKey<ToPkCtx>> Satisfier<ToPkCtx,
 }
 
 pub(crate) type SecpCtx = Secp256k1<All>;
-pub(crate) fn descriptor_to_pk_ctx(secp: &SecpCtx) -> DescriptorPublicKeyCtx<'_, All> {
-    // Create a `to_pk_ctx` with a dummy derivation index, since we always use this on descriptor
-    // that have already been derived with `Descriptor::derive()`, so the child number added here
-    // is ignored.
-    DescriptorPublicKeyCtx::new(secp, bip32::ChildNumber::Normal { index: 0 })
-}
 
 pub struct ChunksIterator<I: Iterator> {
     iter: I,

testutils-macros/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "bdk-testutils-macros"
-version = "0.2.0"
+version = "0.3.0"
 authors = ["Alekos Filini <alekos.filini@gmail.com>"]
 edition = "2018"
 homepage = "https://bitcoindevkit.org"

testutils-macros/src/lib.rs

@@ -307,7 +307,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     wallet.sync(noop_progress(), None).unwrap();
                     assert_eq!(wallet.get_balance().unwrap(), 50_000);
 
-                    let (psbt, details) = wallet.create_tx(TxBuilder::with_recipients(vec![(node_addr.script_pubkey(), 25_000)])).unwrap();
+                    let mut builder = wallet.build_tx();
+                    builder.add_recipient(node_addr.script_pubkey(), 25_000);
+                    let (psbt, details) = builder.finish().unwrap();
                     let (psbt, finalized) = wallet.sign(psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     let tx = psbt.extract_tx();
@@ -334,7 +336,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     wallet.sync(noop_progress(), None).unwrap();
                     assert_eq!(wallet.get_balance().unwrap(), 50_000);
 
-                    let (psbt, details) = wallet.create_tx(TxBuilder::with_recipients(vec![(node_addr.script_pubkey(), 25_000)])).unwrap();
+                    let mut builder = wallet.build_tx();
+                    builder.add_recipient(node_addr.script_pubkey(), 25_000);
+                    let (psbt, details) = builder.finish().unwrap();
                     let (psbt, finalized) = wallet.sign(psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     let sent_txid = wallet.broadcast(psbt.extract_tx()).unwrap();
@@ -373,7 +377,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
 
                     let mut total_sent = 0;
                     for _ in 0..5 {
-                        let (psbt, details) = wallet.create_tx(TxBuilder::with_recipients(vec![(node_addr.script_pubkey().clone(), 5_000)])).unwrap();
+                        let mut builder = wallet.build_tx();
+                        builder.add_recipient(node_addr.script_pubkey(), 5_000);
+                        let (psbt, details) = builder.finish().unwrap();
                         let (psbt, finalized) = wallet.sign(psbt, None).unwrap();
                         assert!(finalized, "Cannot finalize transaction");
                         wallet.broadcast(psbt.extract_tx()).unwrap();
@@ -405,7 +411,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     wallet.sync(noop_progress(), None).unwrap();
                     assert_eq!(wallet.get_balance().unwrap(), 50_000);
 
-                    let (psbt, details) = wallet.create_tx(TxBuilder::with_recipients(vec![(node_addr.script_pubkey().clone(), 5_000)]).enable_rbf()).unwrap();
+                    let mut builder = wallet.build_tx();
+                    builder.add_recipient(node_addr.script_pubkey().clone(), 5_000).enable_rbf();
+                    let (psbt, details) = builder.finish().unwrap();
                     let (psbt, finalized) = wallet.sign(psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     wallet.broadcast(psbt.extract_tx()).unwrap();
@@ -413,7 +421,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     assert_eq!(wallet.get_balance().unwrap(), 50_000 - details.fees - 5_000);
                     assert_eq!(wallet.get_balance().unwrap(), details.received);
 
-                    let (new_psbt, new_details) = wallet.bump_fee(&details.txid, TxBuilder::new().fee_rate(FeeRate::from_sat_per_vb(2.1))).unwrap();
+                    let mut builder = wallet.build_fee_bump(details.txid).unwrap();
+                    builder.fee_rate(FeeRate::from_sat_per_vb(2.1));
+                    let (new_psbt, new_details) = builder.finish().unwrap();
                     let (new_psbt, finalized) = wallet.sign(new_psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     wallet.broadcast(new_psbt.extract_tx()).unwrap();
@@ -437,7 +447,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     wallet.sync(noop_progress(), None).unwrap();
                     assert_eq!(wallet.get_balance().unwrap(), 50_000);
 
-                    let (psbt, details) = wallet.create_tx(TxBuilder::with_recipients(vec![(node_addr.script_pubkey().clone(), 49_000)]).enable_rbf()).unwrap();
+                    let mut builder = wallet.build_tx();
+                    builder.add_recipient(node_addr.script_pubkey().clone(), 49_000).enable_rbf();
+                    let (psbt, details) = builder.finish().unwrap();
                     let (psbt, finalized) = wallet.sign(psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     wallet.broadcast(psbt.extract_tx()).unwrap();
@@ -445,8 +457,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     assert_eq!(wallet.get_balance().unwrap(), 1_000 - details.fees);
                     assert_eq!(wallet.get_balance().unwrap(), details.received);
 
-                    let (new_psbt, new_details) = wallet.bump_fee(&details.txid, TxBuilder::new().fee_rate(FeeRate::from_sat_per_vb(5.0))).unwrap();
-
+                    let mut builder = wallet.build_fee_bump(details.txid).unwrap();
+                    builder.fee_rate(FeeRate::from_sat_per_vb(5.0));
+                    let (new_psbt, new_details) = builder.finish().unwrap();
                     let (new_psbt, finalized) = wallet.sign(new_psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     wallet.broadcast(new_psbt.extract_tx()).unwrap();
@@ -470,7 +483,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     wallet.sync(noop_progress(), None).unwrap();
                     assert_eq!(wallet.get_balance().unwrap(), 75_000);
 
-                    let (psbt, details) = wallet.create_tx(TxBuilder::with_recipients(vec![(node_addr.script_pubkey().clone(), 49_000)]).enable_rbf()).unwrap();
+                    let mut builder = wallet.build_tx();
+                    builder.add_recipient(node_addr.script_pubkey().clone(), 49_000).enable_rbf();
+                    let (psbt, details) = builder.finish().unwrap();
                     let (psbt, finalized) = wallet.sign(psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     wallet.broadcast(psbt.extract_tx()).unwrap();
@@ -478,8 +493,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     assert_eq!(wallet.get_balance().unwrap(), 26_000 - details.fees);
                     assert_eq!(details.received, 1_000 - details.fees);
 
-                    let (new_psbt, new_details) = wallet.bump_fee(&details.txid, TxBuilder::new().fee_rate(FeeRate::from_sat_per_vb(10.0))).unwrap();
-
+                    let mut builder = wallet.build_fee_bump(details.txid).unwrap();
+                    builder.fee_rate(FeeRate::from_sat_per_vb(10.0));
+                    let (new_psbt, new_details) = builder.finish().unwrap();
                     let (new_psbt, finalized) = wallet.sign(new_psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     wallet.broadcast(new_psbt.extract_tx()).unwrap();
@@ -501,7 +517,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     wallet.sync(noop_progress(), None).unwrap();
                     assert_eq!(wallet.get_balance().unwrap(), 75_000);
 
-                    let (psbt, details) = wallet.create_tx(TxBuilder::with_recipients(vec![(node_addr.script_pubkey().clone(), 49_000)]).enable_rbf()).unwrap();
+                    let mut builder = wallet.build_tx();
+                    builder.add_recipient(node_addr.script_pubkey().clone(), 49_000).enable_rbf();
+                    let (psbt, details) = builder.finish().unwrap();
                     let (psbt, finalized) = wallet.sign(psbt, None).unwrap();
                     assert!(finalized, "Cannot finalize transaction");
                     wallet.broadcast(psbt.extract_tx()).unwrap();
@@ -509,7 +527,9 @@ pub fn bdk_blockchain_tests(attr: TokenStream, item: TokenStream) -> TokenStream
                     assert_eq!(wallet.get_balance().unwrap(), 26_000 - details.fees);
                     assert_eq!(details.received, 1_000 - details.fees);
 
-                    let (new_psbt, new_details) = wallet.bump_fee(&details.txid, TxBuilder::new().fee_rate(FeeRate::from_sat_per_vb(123.0))).unwrap();
+                    let mut builder = wallet.build_fee_bump(details.txid).unwrap();
+                    builder.fee_rate(FeeRate::from_sat_per_vb(123.0));
+                    let (new_psbt, new_details) = builder.finish().unwrap();
                     println!("{:#?}", new_details);
 
                     let (new_psbt, finalized) = wallet.sign(new_psbt, None).unwrap();

testutils/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "bdk-testutils"
-version = "0.2.0"
+version = "0.3.0"
 authors = ["Alekos Filini <alekos.filini@gmail.com>"]
 edition = "2018"
 homepage = "https://bitcoindevkit.org"
@@ -20,6 +20,7 @@ log = "0.4.8"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 serial_test = "0.4"
-bitcoin = "0.25"
-bitcoincore-rpc = "0.12"
-electrum-client = "0.4.0-beta.1"
+bitcoin = "0.26"
+bitcoincore-rpc = "0.13"
+miniscript = "5.1"
+electrum-client = "0.6.0"

testutils/src/lib.rs

@@ -40,7 +40,11 @@ use log::{debug, error, info, trace};
 use bitcoin::consensus::encode::{deserialize, serialize};
 use bitcoin::hashes::hex::{FromHex, ToHex};
 use bitcoin::hashes::sha256d;
-use bitcoin::{Address, Amount, Script, Transaction, Txid};
+use bitcoin::secp256k1::{Secp256k1, Verification};
+use bitcoin::{Address, Amount, PublicKey, Script, Transaction, Txid};
+
+use miniscript::descriptor::DescriptorPublicKey;
+use miniscript::{Descriptor, MiniscriptKey, TranslatePk};
 
 pub use bitcoincore_rpc::bitcoincore_rpc_json::AddressType;
 pub use bitcoincore_rpc::{Auth, Client as RpcClient, RpcApi};
@@ -113,23 +117,62 @@ impl TestIncomingTx {
     }
 }
 
+#[doc(hidden)]
+pub trait TranslateDescriptor {
+    // derive and translate a `Descriptor<DescriptorPublicKey>` into a `Descriptor<PublicKey>`
+    fn derive_translated<C: Verification>(
+        &self,
+        secp: &Secp256k1<C>,
+        index: u32,
+    ) -> Descriptor<PublicKey>;
+}
+
+impl TranslateDescriptor for Descriptor<DescriptorPublicKey> {
+    fn derive_translated<C: Verification>(
+        &self,
+        secp: &Secp256k1<C>,
+        index: u32,
+    ) -> Descriptor<PublicKey> {
+        let translate = |key: &DescriptorPublicKey| -> PublicKey {
+            match key {
+                DescriptorPublicKey::XPub(xpub) => {
+                    xpub.xkey
+                        .derive_pub(secp, &xpub.derivation_path)
+                        .expect("hardened derivation steps")
+                        .public_key
+                }
+                DescriptorPublicKey::SinglePub(key) => key.key,
+            }
+        };
+
+        self.derive(index)
+            .translate_pk_infallible(|pk| translate(pk), |pkh| translate(pkh).to_pubkeyhash())
+    }
+}
+
 #[macro_export]
 macro_rules! testutils {
     ( @external $descriptors:expr, $child:expr ) => ({
         use bitcoin::secp256k1::Secp256k1;
-        use miniscript::descriptor::{Descriptor, DescriptorPublicKey, DescriptorPublicKeyCtx};
+        use miniscript::descriptor::{Descriptor, DescriptorPublicKey, DescriptorTrait};
+
+        use $crate::TranslateDescriptor;
 
         let secp = Secp256k1::new();
-        let deriv_ctx = DescriptorPublicKeyCtx::new(&secp, bitcoin::util::bip32::ChildNumber::from_normal_idx(0).unwrap());
 
-        let parsed = Descriptor::<DescriptorPublicKey>::parse_descriptor(&$descriptors.0).expect("Failed to parse descriptor in `testutils!(@external)`").0;
-        parsed.derive(bitcoin::util::bip32::ChildNumber::from_normal_idx($child).unwrap()).address(bitcoin::Network::Regtest, deriv_ctx).expect("No address form")
+        let parsed = Descriptor::<DescriptorPublicKey>::parse_descriptor(&secp, &$descriptors.0).expect("Failed to parse descriptor in `testutils!(@external)`").0;
+        parsed.derive_translated(&secp, $child).address(bitcoin::Network::Regtest).expect("No address form")
     });
     ( @internal $descriptors:expr, $child:expr ) => ({
-        use miniscript::descriptor::{Descriptor, DescriptorPublicKey};
+        use bitcoin::secp256k1::Secp256k1;
+        use miniscript::descriptor::{Descriptor, DescriptorPublicKey, DescriptorTrait};
 
-        let parsed = Descriptor::<DescriptorPublicKey>::parse_descriptor(&$descriptors.1.expect("Missing internal descriptor")).expect("Failed to parse descriptor in `testutils!(@internal)`").0;
-        parsed.derive(bitcoin::util::bip32::ChildNumber::from_normal_idx($child).unwrap()).address(bitcoin::Network::Regtest).expect("No address form")
+        use $crate::TranslateDescriptor;
+
+        let secp = Secp256k1::new();
+
+        let parsed = Descriptor::<DescriptorPublicKey>::parse_descriptor(&secp, &$descriptors.1.expect("Missing internal descriptor")).expect("Failed to parse descriptor in `testutils!(@internal)`").0;
+        parsed.derive_translated(&secp, $child).address(bitcoin::Network::Regtest).expect("No address form")
     });
     ( @e $descriptors:expr, $child:expr ) => ({ testutils!(@external $descriptors, $child) });
     ( @i $descriptors:expr, $child:expr ) => ({ testutils!(@internal $descriptors, $child) });
@@ -202,6 +245,7 @@ macro_rules! testutils {
         use std::convert::TryInto;
 
         use miniscript::descriptor::{Descriptor, DescriptorPublicKey};
+        use miniscript::TranslatePk;
 
         let mut keys: HashMap<&'static str, (String, Option<String>, Option<String>)> = HashMap::new();
         $(
@@ -209,40 +253,39 @@ macro_rules! testutils {
         )*
 
         let external: Descriptor<String> = FromStr::from_str($external_descriptor).unwrap();
-        let external: Descriptor<String> = external.translate_pk::<_, _, _, &'static str>(|k| {
+        let external: Descriptor<String> = external.translate_pk_infallible::<_, _>(|k| {
             if let Some((key, ext_path, _)) = keys.get(&k.as_str()) {
-                Ok(format!("{}{}", key, ext_path.as_ref().unwrap_or(&"".into())))
+                format!("{}{}", key, ext_path.as_ref().unwrap_or(&"".into()))
             } else {
-                Ok(k.clone())
+                k.clone()
             }
         }, |kh| {
             if let Some((key, ext_path, _)) = keys.get(&kh.as_str()) {
-                Ok(format!("{}{}", key, ext_path.as_ref().unwrap_or(&"".into())))
+                format!("{}{}", key, ext_path.as_ref().unwrap_or(&"".into()))
             } else {
-                Ok(kh.clone())
+                kh.clone()
             }
 
-        }).unwrap();
+        });
         let external = external.to_string();
 
         let mut internal = None::<String>;
         $(
             let string_internal: Descriptor<String> = FromStr::from_str($internal_descriptor).unwrap();
 
-            let string_internal: Descriptor<String> = string_internal.translate_pk::<_, _, _, &'static str>(|k| {
+            let string_internal: Descriptor<String> = string_internal.translate_pk_infallible::<_, _>(|k| {
                 if let Some((key, _, int_path)) = keys.get(&k.as_str()) {
-                    Ok(format!("{}{}", key, int_path.as_ref().unwrap_or(&"".into())))
+                    format!("{}{}", key, int_path.as_ref().unwrap_or(&"".into()))
                 } else {
-                    Ok(k.clone())
+                    k.clone()
                 }
             }, |kh| {
                 if let Some((key, _, int_path)) = keys.get(&kh.as_str()) {
-                    Ok(format!("{}{}", key, int_path.as_ref().unwrap_or(&"".into())))
+                    format!("{}{}", key, int_path.as_ref().unwrap_or(&"".into()))
                 } else {
-                    Ok(kh.clone())
+                    kh.clone()
                 }
-
-            }).unwrap();
+            });
             internal = Some(string_internal.to_string());
         )*