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Co-authored-by: str4d <thestr4d@gmail.com>

qa/rpc-tests/wallet_orchard.py

@@ -57,12 +57,12 @@ class WalletOrchardTest(BitcoinTestFramework):
         myopid = self.nodes[0].z_sendmany(get_coinbase_address(self.nodes[0]), recipients, 1, 0)
         wait_and_assert_operationid_status(self.nodes[0], myopid)
 
-        # Mine the tx & activate Orchard
+        # Mine the tx & activate NU5
         self.sync_all()
         self.nodes[0].generate(10)
         self.sync_all()
 
-        # Check the value on saplingAddr2
+        # Check the value sent to saplingAddr2 was received in node 2's account
         assert_equal(
                 {'pools': {'sapling': {'valueZat': Decimal('1000000000')}}, 'minimum_confirmations': 1}, 
                 self.nodes[2].z_getbalanceforaccount(acct2))

src/rust/include/rust/orchard/wallet.h

@@ -40,8 +40,9 @@ void orchard_wallet_free(OrchardWalletPtr* wallet);
 bool orchard_wallet_reset(OrchardWalletPtr* wallet);
 
 /**
- * Adds a checkpoint to the wallet's note commitment tree to enable
- * a future rewind.
+ * Checkpoint the note commitment tree. This returns `false` and leaves the note
+ * commitment tree unmodified if the block height specified is not the successor
+ * to the last block height checkpointed.
  */
 bool orchard_wallet_checkpoint(
         OrchardWalletPtr* wallet,
@@ -55,7 +56,9 @@ bool orchard_wallet_checkpoint(
 bool orchard_wallet_is_checkpointed(const OrchardWalletPtr* wallet);
 
 /**
- * Rewinds to the most recently added checkpoint.
+ * Rewinds to the most recent checkpoint, and marks as unspent any notes
+ * previously identified as having been spent by transactions in the
+ * latest block.
  */
 bool orchard_wallet_rewind(
         OrchardWalletPtr* wallet,

src/wallet/orchard.h

@@ -78,8 +78,8 @@ public:
 
     /**
      * Checkpoint the note commitment tree. This returns `false` and leaves the note
-     * commitment tree unmodified if the block height does not match the last block
-     * height scanned for transactions. This must be called exactly once per block.
+     * commitment tree unmodified if the block height specified is not the successor
+     * to the last block height checkpointed.
      */
     bool CheckpointNoteCommitmentTree(int nBlockHeight) {
         assert(nBlockHeight >= 0);
@@ -94,7 +94,7 @@ public:
     }
 
     /**
-     * Rewind to the most recent checkpoint, and mark as unspent any notes
+     * Rewinds to the most recent checkpoint, and marks as unspent any notes
      * previously identified as having been spent by transactions in the
      * latest block.
      */