wallet: Reload watchonly and solvables wallets after migration

When migrating, create the watchonly and solvables wallets without a
context. Then unload and reload them after migration completes, as we do
for the actual wallet.

There is also additional handling for a failed reload.

src/wallet/wallet.cpp

@@ -4083,6 +4083,10 @@ bool DoMigration(CWallet& wallet, WalletContext& context, bilingual_str& error,
         DatabaseOptions options;
         options.require_existing = false;
         options.require_create = true;
+        options.require_format = DatabaseFormat::SQLITE;
+
+        WalletContext empty_context;
+        empty_context.args = context.args;
 
         // Make the wallets
         options.create_flags = WALLET_FLAG_DISABLE_PRIVATE_KEYS | WALLET_FLAG_BLANK_WALLET | WALLET_FLAG_DESCRIPTORS;
@@ -4098,8 +4102,14 @@ bool DoMigration(CWallet& wallet, WalletContext& context, bilingual_str& error,
             DatabaseStatus status;
             std::vector<bilingual_str> warnings;
             std::string wallet_name = wallet.GetName() + "_watchonly";
-            data->watchonly_wallet = CreateWallet(context, wallet_name, std::nullopt, options, status, error, warnings);
+            std::unique_ptr<WalletDatabase> database = MakeWalletDatabase(wallet_name, options, status, error);
-            if (status != DatabaseStatus::SUCCESS) {
+            if (!database) {
+                error = strprintf(_("Wallet file creation failed: %s"), error);
+                return false;
+            }
+
+            data->watchonly_wallet = CWallet::Create(empty_context, wallet_name, std::move(database), options.create_flags, error, warnings);
+            if (!data->watchonly_wallet) {
                 error = _("Error: Failed to create new watchonly wallet");
                 return false;
             }
@@ -4129,8 +4139,14 @@ bool DoMigration(CWallet& wallet, WalletContext& context, bilingual_str& error,
             DatabaseStatus status;
             std::vector<bilingual_str> warnings;
             std::string wallet_name = wallet.GetName() + "_solvables";
-            data->solvable_wallet = CreateWallet(context, wallet_name, std::nullopt, options, status, error, warnings);
+            std::unique_ptr<WalletDatabase> database = MakeWalletDatabase(wallet_name, options, status, error);
-            if (status != DatabaseStatus::SUCCESS) {
+            if (!database) {
+                error = strprintf(_("Wallet file creation failed: %s"), error);
+                return false;
+            }
+
+            data->solvable_wallet = CWallet::Create(empty_context, wallet_name, std::move(database), options.create_flags, error, warnings);
+            if (!data->solvable_wallet) {
                 error = _("Error: Failed to create new watchonly wallet");
                 return false;
             }
@@ -4233,47 +4249,69 @@ util::Result<MigrationResult> MigrateLegacyToDescriptor(const std::string& walle
         success = DoMigration(*local_wallet, context, error, res);
     }
 
+    // In case of reloading failure, we need to remember the wallet dirs to remove
+    // Set is used as it may be populated with the same wallet directory paths multiple times,
+    // both before and after reloading. This ensures the set is complete even if one of the wallets
+    // fails to reload.
+    std::set<fs::path> wallet_dirs;
     if (success) {
-        // Migration successful, unload the wallet locally, then reload it.
+        // Migration successful, unload all wallets locally, then reload them.
-        assert(local_wallet.use_count() == 1);
+        const auto& reload_wallet = [&](std::shared_ptr<CWallet>& to_reload) {
-        local_wallet.reset();
+            assert(to_reload.use_count() == 1);
-        res.wallet = LoadWallet(context, wallet_name, /*load_on_start=*/std::nullopt, options, status, error, warnings);
+            std::string name = to_reload->GetName();
+            wallet_dirs.insert(fs::PathFromString(to_reload->GetDatabase().Filename()).parent_path());
+            to_reload.reset();
+            to_reload = LoadWallet(context, name, /*load_on_start=*/std::nullopt, options, status, error, warnings);
+            return to_reload != nullptr;
+        };
+        // Reload the main wallet
+        success = reload_wallet(local_wallet);
+        res.wallet = local_wallet;
         res.wallet_name = wallet_name;
-    } else {
+        if (success && res.watchonly_wallet) {
+            // Reload watchonly
+            success = reload_wallet(res.watchonly_wallet);
+        }
+        if (success && res.solvables_wallet) {
+            // Reload solvables
+            success = reload_wallet(res.solvables_wallet);
+        }
+    }
+    if (!success) {
         // Migration failed, cleanup
         // Copy the backup to the actual wallet dir
         fs::path temp_backup_location = fsbridge::AbsPathJoin(GetWalletDir(), backup_filename);
         fs::copy_file(backup_path, temp_backup_location, fs::copy_options::none);
 
-        // Remember this wallet's walletdir to remove after unloading
-        std::vector<fs::path> wallet_dirs;
-        wallet_dirs.emplace_back(fs::PathFromString(local_wallet->GetDatabase().Filename()).parent_path());
-
-        // Unload the wallet locally
-        assert(local_wallet.use_count() == 1);
-        local_wallet.reset();
-
         // Make list of wallets to cleanup
         std::vector<std::shared_ptr<CWallet>> created_wallets;
+        if (local_wallet) created_wallets.push_back(std::move(local_wallet));
         if (res.watchonly_wallet) created_wallets.push_back(std::move(res.watchonly_wallet));
         if (res.solvables_wallet) created_wallets.push_back(std::move(res.solvables_wallet));
 
         // Get the directories to remove after unloading
         for (std::shared_ptr<CWallet>& w : created_wallets) {
-            wallet_dirs.emplace_back(fs::PathFromString(w->GetDatabase().Filename()).parent_path());
+            wallet_dirs.emplace(fs::PathFromString(w->GetDatabase().Filename()).parent_path());
         }
 
         // Unload the wallets
         for (std::shared_ptr<CWallet>& w : created_wallets) {
+            if (w->HaveChain()) {
+                // Unloading for wallets that were loaded for normal use
                 if (!RemoveWallet(context, w, /*load_on_start=*/false)) {
                     error += _("\nUnable to cleanup failed migration");
                     return util::Error{error};
                 }
                 UnloadWallet(std::move(w));
+            } else {
+                // Unloading for wallets in local context
+                assert(w.use_count() == 1);
+                w.reset();
+            }
         }
 
         // Delete the wallet directories
-        for (fs::path& dir : wallet_dirs) {
+        for (const fs::path& dir : wallet_dirs) {
             fs::remove_all(dir);
         }
 

test/functional/wallet_migration.py

@@ -848,7 +848,7 @@ class WalletMigrationTest(BitcoinTestFramework):
         wallet.addmultisigaddress(2, [wallet.getnewaddress(), get_generate_key().pubkey])
         wallet.importaddress(get_generate_key().p2pkh_addr)
 
-        assert_raises_rpc_error(-4, "Failed to create new watchonly wallet", wallet.migratewallet)
+        assert_raises_rpc_error(-4, "Failed to create database", wallet.migratewallet)
 
         assert "failed" in self.nodes[0].listwallets()
         assert "failed_watchonly" not in self.nodes[0].listwallets()