command: Add a function to be called after the main function

The main function is run inside a sqlite transaction context, but there
are a few rare cases where we want to call a function after the main
function and outside of a transaction (such as using the sqlite 'VACUUM'
operation). This gives us a way to do that.

Signed-off-by: Anna Schumaker <anna@nowheycreamery.com>

tests/test_commands.py

@@ -24,9 +24,15 @@ class TestCommand(unittest.TestCase):
         self.assertEqual(self.command.parser.description, "description")
         self.assertEqual(self.command.parser._defaults["function"],
                          self.command.do_command)
+        self.assertEqual(self.command.parser._defaults["done"],
+                         self.command.do_done)
         self.assertEqual(self.command.sql, self.sql)
 
     def test_do_command(self):
         """Test the do_command() function."""
         with self.assertRaises(NotImplementedError):
             self.command.do_command(argparse.Namespace())
+
+    def test_do_done(self):
+        """Test the do_done() function."""
+        self.command.do_done(argparse.Namespace())

tests/test_xfstestsdb.py

@@ -37,16 +37,18 @@ class TestXfstestsdb(unittest.TestCase):
     def test_run(self):
         """Test running the xfstestsdb."""
         parser = self.xfstestsdb.subparser.add_parser("test-run", help="help")
+        test_done = unittest.mock.Mock()
         test_passed = False
 
         def test_func(args: argparse.Namespace) -> None:
             nonlocal test_passed
             self.assertTrue(self.xfstestsdb.sql.sql.in_transaction)
             test_passed = True
-        parser.set_defaults(function=test_func)
+        parser.set_defaults(function=test_func, done=test_done)
 
         self.xfstestsdb.run(["test-run"])
         self.assertTrue(test_passed)
+        test_done.assert_called()
 
     @unittest.mock.patch("sys.stdout", new_callable=io.StringIO)
     def test_version(self, mock_stdout: io.StringIO):

xfstestsdb/__init__.py

@@ -24,7 +24,8 @@ class Command:
     def __init__(self) -> None:
         """Initialize the xfstestsdb command."""
         self.parser = argparse.ArgumentParser()
-        self.parser.set_defaults(function=lambda x: self.parser.print_usage())
+        self.parser.set_defaults(function=lambda x: self.parser.print_usage(),
+                                 done=lambda x: None)
         self.parser.add_argument("--version", action="store_true",
                                  help="show version number and exit")
         self.subparser = self.parser.add_subparsers(title="commands")
@@ -55,3 +56,4 @@ class Command:
         else:
             with self.sql:
                 parsed.function(parsed)
+            parsed.done(parsed)

xfstestsdb/commands.py

@@ -12,8 +12,12 @@ class Command:
         """Set up the Command."""
         self.parser = subparser.add_parser(name, help=help, **kwargs)
         self.parser.set_defaults(function=self.do_command)
+        self.parser.set_defaults(done=self.do_done)
         self.sql = sql
 
     def do_command(self, args: argparse.Namespace) -> None:
         """Do something."""
         raise NotImplementedError
+
+    def do_done(self, args: argparse.Namespace) -> None:
+        """Run after the main command, outside of a transaction."""