Merge bitcoin/bitcoin#25934: wallet, rpc: add label to listsinceblock

4e362c2 doc: add release note for 25934 (brunoerg)
fe488b4 test: add coverage for `label` in `listsinceblock` (brunoerg)
722e9a4 wallet, rpc: add `label` to `listsinceblock` (brunoerg)
852891f refactor, wallet: use optional for `label` in `ListTransactions` (brunoerg)

Pull request description:

  This PR adds `label` parameter to `listsinceblock` to be able to fetch all incoming transactions having the specified label since a specific block.

  It's possible to use it in `listtransactions`, however, it's only possible to set the number of transactions to return, not a specific block to fetch from. `getreceivedbylabel` only returns the total amount received, not the txs info. `listreceivedbylabel` doesn't list all the informations about the transactions and it's not possible to fetch since a block.

ACKs for top commit:
  achow101:
    ACK 4e362c2
  w0xlt:
    ACK bitcoin/bitcoin@4e362c2
  aureleoules:
    ACK 4e362c2

Tree-SHA512: fbde5db8cebf7a27804154fa61997b5155ad512e978cebb78c17acab9efcb624ea5f39d649899d12e5e675f80d4d0064cae8132b864de0d93a8d1e6fbcb9a737

Author: achow101

doc/release-notes-25934.md

@@ -0,0 +1,8 @@
+Low-level changes
+=================
+
+RPC
+---
+
+- RPC `listsinceblock` now accepts an optional `label` argument
+  to fetch incoming transactions having the specified label. (#25934)

src/wallet/rpc/transactions.cpp

@@ -316,7 +316,7 @@ static void MaybePushAddress(UniValue & entry, const CTxDestination &dest)
  */
 template <class Vec>
 static void ListTransactions(const CWallet& wallet, const CWalletTx& wtx, int nMinDepth, bool fLong,
-                             Vec& ret, const isminefilter& filter_ismine, const std::string* filter_label,
+                             Vec& ret, const isminefilter& filter_ismine, const std::optional<std::string>& filter_label,
                              bool include_change = false)
     EXCLUSIVE_LOCKS_REQUIRED(wallet.cs_wallet)
 {
@@ -329,7 +329,7 @@ static void ListTransactions(const CWallet& wallet, const CWalletTx& wtx, int nM
     bool involvesWatchonly = CachedTxIsFromMe(wallet, wtx, ISMINE_WATCH_ONLY);
 
     // Sent
-    if (!filter_label)
+    if (!filter_label.has_value())
     {
         for (const COutputEntry& s : listSent)
         {
@@ -362,7 +362,7 @@ static void ListTransactions(const CWallet& wallet, const CWalletTx& wtx, int nM
             if (address_book_entry) {
                 label = address_book_entry->GetLabel();
             }
-            if (filter_label && label != *filter_label) {
+            if (filter_label.has_value() && label != filter_label.value()) {
                 continue;
             }
             UniValue entry(UniValue::VOBJ);
@@ -485,10 +485,10 @@ RPCHelpMan listtransactions()
     // the user could have gotten from another RPC command prior to now
     pwallet->BlockUntilSyncedToCurrentChain();
 
-    const std::string* filter_label = nullptr;
+    std::optional<std::string> filter_label;
     if (!request.params[0].isNull() && request.params[0].get_str() != "*") {
-        filter_label = &request.params[0].get_str();
-        if (filter_label->empty()) {
+        filter_label = request.params[0].get_str();
+        if (filter_label.value().empty()) {
             throw JSONRPCError(RPC_INVALID_PARAMETER, "Label argument must be a valid label name or \"*\".");
         }
     }
@@ -552,6 +552,7 @@ RPCHelpMan listsinceblock()
                     {"include_removed", RPCArg::Type::BOOL, RPCArg::Default{true}, "Show transactions that were removed due to a reorg in the \"removed\" array\n"
                                                                        "(not guaranteed to work on pruned nodes)"},
                     {"include_change", RPCArg::Type::BOOL, RPCArg::Default{false}, "Also add entries for change outputs.\n"},
+                    {"label", RPCArg::Type::STR, RPCArg::Optional::OMITTED_NAMED_ARG, "Return only incoming transactions paying to addresses with the specified label.\n"},
                 },
                 RPCResult{
                     RPCResult::Type::OBJ, "", "",
@@ -634,6 +635,11 @@ RPCHelpMan listsinceblock()
     bool include_removed = (request.params[3].isNull() || request.params[3].get_bool());
     bool include_change = (!request.params[4].isNull() && request.params[4].get_bool());
 
+    std::optional<std::string> filter_label;
+    if (!request.params[5].isNull()) {
+        filter_label = request.params[5].get_str();
+    }
+
     int depth = height ? wallet.GetLastBlockHeight() + 1 - *height : -1;
 
     UniValue transactions(UniValue::VARR);
@@ -642,7 +648,7 @@ RPCHelpMan listsinceblock()
         const CWalletTx& tx = pairWtx.second;
 
         if (depth == -1 || abs(wallet.GetTxDepthInMainChain(tx)) < depth) {
-            ListTransactions(wallet, tx, 0, true, transactions, filter, /*filter_label=*/nullptr, /*include_change=*/include_change);
+            ListTransactions(wallet, tx, 0, true, transactions, filter, filter_label, include_change);
         }
     }
 
@@ -659,7 +665,7 @@ RPCHelpMan listsinceblock()
             if (it != wallet.mapWallet.end()) {
                 // We want all transactions regardless of confirmation count to appear here,
                 // even negative confirmation ones, hence the big negative.
-                ListTransactions(wallet, it->second, -100000000, true, removed, filter, /*filter_label=*/nullptr, /*include_change=*/include_change);
+                ListTransactions(wallet, it->second, -100000000, true, removed, filter, filter_label, include_change);
             }
         }
         blockId = block.hashPrevBlock;
@@ -777,7 +783,7 @@ RPCHelpMan gettransaction()
     WalletTxToJSON(*pwallet, wtx, entry);
 
     UniValue details(UniValue::VARR);
-    ListTransactions(*pwallet, wtx, 0, false, details, filter, /*filter_label=*/nullptr);
+    ListTransactions(*pwallet, wtx, 0, false, details, filter, /*filter_label=*/std::nullopt);
     entry.pushKV("details", details);
 
     std::string strHex = EncodeHexTx(*wtx.tx, pwallet->chain().rpcSerializationFlags());

test/functional/wallet_listsinceblock.py

@@ -49,6 +49,7 @@ def run_test(self):
             self.test_desc()
         self.test_send_to_self()
         self.test_op_return()
+        self.test_label()
 
     def test_no_blockhash(self):
         self.log.info("Test no blockhash")
@@ -465,6 +466,20 @@ def test_op_return(self):
 
         assert 'address' not in op_ret_tx
 
+    def test_label(self):
+        self.log.info('Test passing "label" argument fetches incoming transactions having the specified label')
+        new_addr = self.nodes[1].getnewaddress(label="new_addr", address_type="bech32")
+
+        self.nodes[2].sendtoaddress(address=new_addr, amount="0.001")
+        self.generate(self.nodes[2], 1)
+
+        for label in ["new_addr", ""]:
+            new_addr_transactions = self.nodes[1].listsinceblock(label=label)["transactions"]
+            assert_equal(len(new_addr_transactions), 1)
+            assert_equal(new_addr_transactions[0]["label"], label)
+            if label == "new_addr":
+                assert_equal(new_addr_transactions[0]["address"], new_addr)
+
 
 if __name__ == '__main__':
     ListSinceBlockTest().main()