rust: add error for script pubkey not found

Author: LeoComandini

subprojects/gdk_rust/gdk_electrum/src/error.rs

@@ -34,6 +34,7 @@ pub enum Error {
     WalletNotInitialized,
     MissingMasterBlindingKey,
     TxNotFound(String),
+    ScriptPubkeyNotFound,
     AddrParse(String),
     InvalidElectrumUrl(String),
     Bitcoin(bitcoin::util::Error),
@@ -108,6 +109,7 @@ impl Display for Error {
             Error::InvalidElectrumUrl(url) => write!(f, "Invalid Electrum URL: {}", url),
             Error::PsetAndTxMismatch => write!(f, "PSET and Tx mismatch"),
             Error::TxNotFound(txid) => write!(f, "Transaction not found ({})", txid),
+            Error::ScriptPubkeyNotFound => write!(f, "Scriptpubkey not found"),
         }
     }
 }

subprojects/gdk_rust/gdk_electrum/src/store.rs

@@ -480,9 +480,7 @@ impl RawAccountCache {
     }
 
     pub fn get_path(&self, script_pubkey: &BEScript) -> Result<&DerivationPath, Error> {
-        self.paths
-            .get(script_pubkey)
-            .ok_or_else(|| Error::Generic("can't find derivation path".into()))
+        self.paths.get(script_pubkey).ok_or_else(|| Error::ScriptPubkeyNotFound)
     }
 }