test: Perform backup filename checks in migrate_and_get_rpc

Some test cases were unnecessarily checking the backup filename, which
involved setting the mocktime before `migrate_and_get_rpc`. However,
this could cause a failure if the test was slow since
`migrate_and_get_rpc` also sets the mocktime. Since it also already
checks that the backup file is named correctly, there's no need for
those tests to also do their own mocktime and filename check.

Author: achow101

test/functional/wallet_migration.py

@@ -128,7 +128,8 @@ def migrate_and_get_rpc(self, wallet_name, **kwargs):
             if w["name"] == wallet_name:
                 assert_equal(w["warnings"], ["This wallet is a legacy wallet and will need to be migrated with migratewallet before it can be loaded"])
 
-        # Mock time so that we can check the backup filename.
+        # migratewallet uses current time in naming the backup file, set a mock time
+        # to check that this works correctly.
         mocked_time = int(time.time())
         self.master_node.setmocktime(mocked_time)
         # Migrate, checking that rescan does not occur
@@ -148,8 +149,10 @@ def migrate_and_get_rpc(self, wallet_name, **kwargs):
         else:
             backup_prefix = os.path.basename(os.path.realpath(self.old_node.wallets_path / wallet_name))
 
-        expected_backup_path = self.master_node.wallets_path / f"{backup_prefix}_{mocked_time}.legacy.bak"
+        backup_filename = f"{backup_prefix}_{mocked_time}.legacy.bak"
+        expected_backup_path = self.master_node.wallets_path / backup_filename
         assert_equal(str(expected_backup_path), migrate_info['backup_path'])
+        assert {"name": backup_filename} not in self.master_node.listwalletdir()["wallets"]
 
         return migrate_info, wallet
 
@@ -593,12 +596,7 @@ def test_wallet_with_relative_path(self):
         self.generate(self.master_node, 1)
         bals = wallet.getbalances()
 
-        # migratewallet uses current time in naming the backup file, set a mock time
-        # to check that this works correctly.
-        curr_time = int(time.time())
-        self.master_node.setmocktime(curr_time)
         migrate_res, wallet = self.migrate_and_get_rpc(relative_name)
-        self.master_node.setmocktime(0)
 
         # Check that the wallet was migrated, knows the right txid, and has the right balance.
         assert wallet.gettransaction(txid)
@@ -665,27 +663,17 @@ def test_default_wallet(self):
         self.log.info("Test migration of the wallet named as the empty string")
         wallet = self.create_legacy_wallet("")
 
-        # Set time to verify backup existence later
-        curr_time = int(time.time())
-        self.master_node.setmocktime(curr_time)
-
         res, wallet = self.migrate_and_get_rpc("")
-        self.master_node.setmocktime(0)
         info = wallet.getwalletinfo()
         assert_equal(info["descriptors"], True)
         assert_equal(info["format"], "sqlite")
 
         walletdir_list = wallet.listwalletdir()
         assert {"name": info["walletname"]} in [{"name": w["name"]} for w in walletdir_list["wallets"]]
 
-        # Check backup existence and its non-empty wallet filename
-        backup_filename = f"default_wallet_{curr_time}.legacy.bak"
-        backup_path = self.master_node.wallets_path / backup_filename
-        assert backup_path.exists()
-        assert_equal(str(backup_path), res['backup_path'])
-        assert {"name": backup_filename} not in walletdir_list["wallets"]
-
-        self.master_node.setmocktime(0)
+        # Make sure the backup uses a non-empty filename
+        # migrate_and_get_rpc already checks for backup file existence
+        assert os.path.basename(res["backup_path"]).startswith("default_wallet")
 
     def test_direct_file(self):
         self.log.info("Test migration of a wallet that is not in a wallet directory")