refactor(electrum) put the tx cache in electrum

crates/chain/src/indexed_tx_graph.rs

@@ -352,3 +352,9 @@ pub trait Indexer {
     /// Determines whether the transaction should be included in the index.
     fn is_tx_relevant(&self, tx: &Transaction) -> bool;
 }
+
+impl<A, I> AsRef<TxGraph<A>> for IndexedTxGraph<A, I> {
+    fn as_ref(&self) -> &TxGraph<A> {
+        &self.graph
+    }
+}

crates/chain/src/spk_client.rs

@@ -1,19 +1,12 @@
 //! Helper types for spk-based blockchain clients.
 
 use crate::{
-    collections::{BTreeMap, HashMap},
-    local_chain::CheckPoint,
-    ConfirmationTimeHeightAnchor, TxGraph,
+    collections::BTreeMap, local_chain::CheckPoint, ConfirmationTimeHeightAnchor, TxGraph,
 };
-use alloc::{boxed::Box, sync::Arc, vec::Vec};
-use bitcoin::{OutPoint, Script, ScriptBuf, Transaction, Txid};
+use alloc::{boxed::Box, vec::Vec};
+use bitcoin::{OutPoint, Script, ScriptBuf, Txid};
 use core::{fmt::Debug, marker::PhantomData, ops::RangeBounds};
 
-/// A cache of [`Arc`]-wrapped full transactions, identified by their [`Txid`]s.
-///
-/// This is used by the chain-source to avoid re-fetching full transactions.
-pub type TxCache = HashMap<Txid, Arc<Transaction>>;
-
 /// Data required to perform a spk-based blockchain client sync.
 ///
 /// A client sync fetches relevant chain data for a known list of scripts, transaction ids and
@@ -24,8 +17,6 @@ pub struct SyncRequest {
     ///
     /// [`LocalChain::tip`]: crate::local_chain::LocalChain::tip
     pub chain_tip: CheckPoint,
-    /// Cache of full transactions, so the chain-source can avoid re-fetching.
-    pub tx_cache: TxCache,
     /// Transactions that spend from or to these indexed script pubkeys.
     pub spks: Box<dyn ExactSizeIterator<Item = ScriptBuf> + Send>,
     /// Transactions with these txids.
@@ -39,36 +30,12 @@ impl SyncRequest {
     pub fn from_chain_tip(cp: CheckPoint) -> Self {
         Self {
             chain_tip: cp,
-            tx_cache: TxCache::new(),
             spks: Box::new(core::iter::empty()),
             txids: Box::new(core::iter::empty()),
             outpoints: Box::new(core::iter::empty()),
         }
     }
 
-    /// Add to the [`TxCache`] held by the request.
-    ///
-    /// This consumes the [`SyncRequest`] and returns the updated one.
-    #[must_use]
-    pub fn cache_txs<T>(mut self, full_txs: impl IntoIterator<Item = (Txid, T)>) -> Self
-    where
-        T: Into<Arc<Transaction>>,
-    {
-        self.tx_cache = full_txs
-            .into_iter()
-            .map(|(txid, tx)| (txid, tx.into()))
-            .collect();
-        self
-    }
-
-    /// Add all transactions from [`TxGraph`] into the [`TxCache`].
-    ///
-    /// This consumes the [`SyncRequest`] and returns the updated one.
-    #[must_use]
-    pub fn cache_graph_txs<A>(self, graph: &TxGraph<A>) -> Self {
-        self.cache_txs(graph.full_txs().map(|tx_node| (tx_node.txid, tx_node.tx)))
-    }
-
     /// Set the [`Script`]s that will be synced against.
     ///
     /// This consumes the [`SyncRequest`] and returns the updated one.
@@ -227,8 +194,6 @@ pub struct FullScanRequest<K> {
     ///
     /// [`LocalChain::tip`]: crate::local_chain::LocalChain::tip
     pub chain_tip: CheckPoint,
-    /// Cache of full transactions, so the chain-source can avoid re-fetching.
-    pub tx_cache: TxCache,
     /// Iterators of script pubkeys indexed by the keychain index.
     pub spks_by_keychain: BTreeMap<K, Box<dyn Iterator<Item = (u32, ScriptBuf)> + Send>>,
 }
@@ -239,34 +204,10 @@ impl<K: Ord + Clone> FullScanRequest<K> {
     pub fn from_chain_tip(chain_tip: CheckPoint) -> Self {
         Self {
             chain_tip,
-            tx_cache: TxCache::new(),
             spks_by_keychain: BTreeMap::new(),
         }
     }
 
-    /// Add to the [`TxCache`] held by the request.
-    ///
-    /// This consumes the [`SyncRequest`] and returns the updated one.
-    #[must_use]
-    pub fn cache_txs<T>(mut self, full_txs: impl IntoIterator<Item = (Txid, T)>) -> Self
-    where
-        T: Into<Arc<Transaction>>,
-    {
-        self.tx_cache = full_txs
-            .into_iter()
-            .map(|(txid, tx)| (txid, tx.into()))
-            .collect();
-        self
-    }
-
-    /// Add all transactions from [`TxGraph`] into the [`TxCache`].
-    ///
-    /// This consumes the [`SyncRequest`] and returns the updated one.
-    #[must_use]
-    pub fn cache_graph_txs<A>(self, graph: &TxGraph<A>) -> Self {
-        self.cache_txs(graph.full_txs().map(|tx_node| (tx_node.txid, tx_node.tx)))
-    }
-
     /// Construct a new [`FullScanRequest`] from a given `chain_tip` and `index`.
     ///
     /// Unbounded script pubkey iterators for each keychain (`K`) are extracted using