zcash_client_backend: Add `target_height` to `SentTransaction`

zcash_client_backend/CHANGELOG.md

@@ -86,6 +86,8 @@ funds to those addresses. See [ZIP 320](https://zips.z.cash/zip-0320) for detail
   - `DecryptedTransaction::new` takes an additional `mined_height` argument.
   - `SentTransaction` now stores its `outputs` and `utxos_spent` fields as
     references to slices, with a corresponding change to `SentTransaction::new`.
+  - `SentTransaction` takes an additional `target_height` argument, which is used
+    to record the target height used in transaction generation.
 - `zcash_client_backend::data_api::fees`
   - When the "transparent-inputs" feature is enabled, `ChangeValue` can also
     represent an ephemeral transparent output in a proposal. Accordingly, the

zcash_client_backend/src/data_api.rs

@@ -1395,6 +1395,7 @@ impl<'a, AccountId> DecryptedTransaction<'a, AccountId> {
 pub struct SentTransaction<'a, AccountId> {
     tx: &'a Transaction,
     created: time::OffsetDateTime,
+    target_height: BlockHeight,
     account: AccountId,
     outputs: &'a [SentTransactionOutput<AccountId>],
     fee_amount: NonNegativeAmount,
@@ -1407,6 +1408,7 @@ impl<'a, AccountId> SentTransaction<'a, AccountId> {
     pub fn new(
         tx: &'a Transaction,
         created: time::OffsetDateTime,
+        target_height: BlockHeight,
         account: AccountId,
         outputs: &'a [SentTransactionOutput<AccountId>],
         fee_amount: NonNegativeAmount,
@@ -1415,6 +1417,7 @@ impl<'a, AccountId> SentTransaction<'a, AccountId> {
         Self {
             tx,
             created,
+            target_height,
             account,
             outputs,
             fee_amount,
@@ -1448,6 +1451,11 @@ impl<'a, AccountId> SentTransaction<'a, AccountId> {
     pub fn utxos_spent(&self) -> &[OutPoint] {
         self.utxos_spent
     }
+
+    /// Returns the block height that this transaction was created to target.
+    pub fn target_height(&self) -> BlockHeight {
+        self.target_height
+    }
 }
 
 /// An output of a transaction generated by the wallet.

zcash_client_backend/src/data_api/wallet.rs

@@ -668,6 +668,7 @@ where
         transactions.push(SentTransaction::new(
             tx,
             created,
+            proposal.min_target_height(),
             account_id,
             &step_result.outputs,
             step_result.fee_amount,

zcash_client_sqlite/src/wallet.rs

@@ -1857,7 +1857,7 @@ pub(crate) fn store_transaction_to_be_sent<P: consensus::Parameters>(
         sent_tx.tx(),
         Some(sent_tx.fee_amount()),
         Some(sent_tx.created()),
-        chain_tip_height(wdb.conn.0)?.map(|h| h + 1),
+        Some(sent_tx.target_height()),
     )?;
 
     let mut detectable_via_scanning = false;

zcash_client_sqlite/src/wallet/init/migrations/tx_retrieval_queue.rs

@@ -1,4 +1,4 @@
-//! A migration to add the `tx_retrieval_queue` table to the database.
+//! Adds tables for tracking transactions to be downloaded for transparent output and/or memo retrieval.
 
 use rusqlite::{named_params, Transaction};
 use schemer_rusqlite::RusqliteMigration;
@@ -24,7 +24,7 @@ impl schemer::Migration for Migration {
     }
 
     fn description(&self) -> &'static str {
-        "Adds a table for tracking transactions to be downloaded for transparent output and/or memo retrieval."
+        "Adds tables for tracking transactions to be downloaded for transparent output and/or memo retrieval."
     }
 }