Merge bitcoin/bitcoin#26761: wallet: fully migrate address book entries for watchonly/solvable wallets

730e14a test: wallet: check that labels are migrated to watchonly wallet (Sebastian Falbesoner)
d5f4ae7 wallet: fully migrate address book entries for watchonly/solvable wallets (Sebastian Falbesoner)

Pull request description:

  Currently `migratewallet` migrates the address book (i.e. labels and purposes) for watchonly and solvable wallets only in RAM, but doesn't persist them on disk. Fix this by adding another loop for both of the special wallet types after which writes the corresponding NAME and PURPOSE entries to the database in a single batch. Also adds a corresponding test that checks if labels were migrated correctly for a watchonly wallet.

ACKs for top commit:
  achow101:
    ACK 730e14a
  furszy:
    code ACK 730e14a, left a non-blocking nit.
  aureleoules:
    ACK 730e14a

Tree-SHA512: 159487e11e858924ef762e0190ccaea185bdff239e3d2280c8d63c4ac2649ec71714dc4d53dec644f03488f91c3b4bbbbf3434dad23bc0fcecb6657f353ea766

Author: achow101

src/wallet/wallet.cpp

@@ -4001,6 +4001,23 @@ bool CWallet::ApplyMigrationData(MigrationData& data, bilingual_str& error)
             }
         }
     }
+
+    // Persist added address book entries (labels, purpose) for watchonly and solvable wallets
+    auto persist_address_book = [](const CWallet& wallet) {
+        LOCK(wallet.cs_wallet);
+        WalletBatch batch{wallet.GetDatabase()};
+        for (const auto& [destination, addr_book_data] : wallet.m_address_book) {
+            auto address{EncodeDestination(destination)};
+            auto purpose{addr_book_data.purpose};
+            auto label{addr_book_data.GetLabel()};
+            // don't bother writing default values (unknown purpose, empty label)
+            if (purpose != "unknown") batch.WritePurpose(address, purpose);
+            if (!label.empty()) batch.WriteName(address, label);
+        }
+    };
+    if (data.watchonly_wallet) persist_address_book(*data.watchonly_wallet);
+    if (data.solvable_wallet) persist_address_book(*data.solvable_wallet);
+
     // Remove the things to delete
     if (dests_to_delete.size() > 0) {
         for (const auto& dest : dests_to_delete) {

test/functional/wallet_migration.py

@@ -258,7 +258,7 @@ def test_other_watchonly(self):
         self.log.info("Test migration of a wallet with watchonly imports")
         imports0 = self.create_legacy_wallet("imports0")
 
-        # Exteranl address label
+        # External address label
         imports0.setlabel(default.getnewaddress(), "external")
 
         # Normal non-watchonly tx
@@ -311,6 +311,13 @@ def test_other_watchonly(self):
         assert_raises_rpc_error(-5, "Invalid or non-wallet transaction id", watchonly.gettransaction, received_txid)
         assert_equal(len(watchonly.listtransactions(include_watchonly=True)), 3)
 
+        # Check that labels were migrated and persisted to watchonly wallet
+        self.nodes[0].unloadwallet("imports0_watchonly")
+        self.nodes[0].loadwallet("imports0_watchonly")
+        labels = watchonly.listlabels()
+        assert "external" in labels
+        assert "imported" in labels
+
     def test_no_privkeys(self):
         default = self.nodes[0].get_wallet_rpc(self.default_wallet_name)