refactor(chain): SyncRequestBuilderExt::check_for_missing_txs

Rename `SyncRequestBuilderExt::check_unconfirmed_statuses` to
`SyncRequestBuilderExt::check_for_missing_txs` and update docs.

Author: evanlinjin

crates/chain/src/indexer/keychain_txout.rs

@@ -882,12 +882,15 @@ pub trait SyncRequestBuilderExt<K> {
     /// Add [`Script`](bitcoin::Script)s that are revealed by the `indexer` but currently unused.
     fn unused_spks_from_indexer(self, indexer: &KeychainTxOutIndex<K>) -> Self;
 
-    /// Add unconfirmed txids and their associated spks.
-    ///
-    /// We expect that the chain source should include these txids in their spk histories. If not,
-    /// the transaction has been evicted for some reason and we will inform the receiving
-    /// structures in the response.
-    fn check_unconfirmed_statuses<A, C>(
+    /// Add txids of unconfirmed transactions and their associated spks to the request to check
+    /// whether they are missing from the mempool.
+    ///
+    /// We expect that the chain source should include these txids in their spk history response. If
+    /// not, it means the transaction has been evicted from the mempool. The chain
+    /// source crate should include the missing transaction's txid in
+    /// [`TxUpdate::missing`](bdk_core::TxUpdate::missing) of
+    /// [`SyncResponse`](bdk_core::spk_client::SyncResponse).
+    fn check_for_missing_txs<A, C>(
         self,
         indexer: &KeychainTxOutIndex<K>,
         canonical_iter: CanonicalIter<A, C>,
@@ -909,7 +912,7 @@ impl<K: Clone + Ord + core::fmt::Debug> SyncRequestBuilderExt<K> for SyncRequest
         self.spks_with_indexes(indexer.unused_spks())
     }
 
-    fn check_unconfirmed_statuses<A, C>(
+    fn check_for_missing_txs<A, C>(
         self,
         indexer: &KeychainTxOutIndex<K>,
         canonical_iter: CanonicalIter<A, C>,

crates/electrum/tests/test_electrum.rs

@@ -135,7 +135,7 @@ pub fn detect_receive_tx_cancel() -> anyhow::Result<()> {
     let sync_request = SyncRequest::builder()
         .chain_tip(chain.tip())
         .revealed_spks_from_indexer(&graph.index, ..)
-        .check_unconfirmed_statuses(
+        .check_for_missing_txs(
             &graph.index,
             graph.graph().canonical_iter(&chain, chain.tip().block_id()),
         );
@@ -163,7 +163,7 @@ pub fn detect_receive_tx_cancel() -> anyhow::Result<()> {
     let sync_request = SyncRequest::builder()
         .chain_tip(chain.tip())
         .revealed_spks_from_indexer(&graph.index, ..)
-        .check_unconfirmed_statuses(
+        .check_for_missing_txs(
             &graph.index,
             graph.graph().canonical_iter(&chain, chain.tip().block_id()),
         );

crates/esplora/tests/async_ext.rs

@@ -94,7 +94,7 @@ pub async fn detect_receive_tx_cancel() -> anyhow::Result<()> {
     let sync_request = SyncRequest::builder()
         .chain_tip(chain.tip())
         .revealed_spks_from_indexer(&graph.index, ..)
-        .check_unconfirmed_statuses(
+        .check_for_missing_txs(
             &graph.index,
             graph.graph().canonical_iter(&chain, chain.tip().block_id()),
         );
@@ -122,7 +122,7 @@ pub async fn detect_receive_tx_cancel() -> anyhow::Result<()> {
     let sync_request = SyncRequest::builder()
         .chain_tip(chain.tip())
         .revealed_spks_from_indexer(&graph.index, ..)
-        .check_unconfirmed_statuses(
+        .check_for_missing_txs(
             &graph.index,
             graph.graph().canonical_iter(&chain, chain.tip().block_id()),
         );

crates/esplora/tests/blocking_ext.rs

@@ -94,7 +94,7 @@ pub fn detect_receive_tx_cancel() -> anyhow::Result<()> {
     let sync_request = SyncRequest::builder()
         .chain_tip(chain.tip())
         .revealed_spks_from_indexer(&graph.index, ..)
-        .check_unconfirmed_statuses(
+        .check_for_missing_txs(
             &graph.index,
             graph.graph().canonical_iter(&chain, chain.tip().block_id()),
         );
@@ -122,7 +122,7 @@ pub fn detect_receive_tx_cancel() -> anyhow::Result<()> {
     let sync_request = SyncRequest::builder()
         .chain_tip(chain.tip())
         .revealed_spks_from_indexer(&graph.index, ..)
-        .check_unconfirmed_statuses(
+        .check_for_missing_txs(
             &graph.index,
             graph.graph().canonical_iter(&chain, chain.tip().block_id()),
         );