Move everything in the root

src/error.rs

@@ -0,0 +1,33 @@
+#[derive(Debug)]
+pub enum Error {
+    KeyMismatch(bitcoin::secp256k1::PublicKey, bitcoin::secp256k1::PublicKey),
+    MissingInputUTXO(usize),
+    InvalidU32Bytes(Vec<u8>),
+    Generic(String),
+
+    Encode(bitcoin::consensus::encode::Error),
+    BIP32(bitcoin::util::bip32::Error),
+    Secp256k1(bitcoin::secp256k1::Error),
+    JSON(serde_json::Error),
+
+    #[cfg(any(feature = "key-value-db", feature = "default"))]
+    Sled(sled::Error),
+}
+
+macro_rules! impl_error {
+    ( $from:ty, $to:ident ) => {
+        impl std::convert::From<$from> for Error {
+            fn from(err: $from) -> Self {
+                Error::$to(err)
+            }
+        }
+    };
+}
+
+impl_error!(bitcoin::consensus::encode::Error, Encode);
+impl_error!(bitcoin::util::bip32::Error, BIP32);
+impl_error!(bitcoin::secp256k1::Error, Secp256k1);
+impl_error!(serde_json::Error, JSON);
+
+#[cfg(any(feature = "key-value-db", feature = "default"))]
+impl_error!(sled::Error, Sled);