Function test_parser_error_output_to

tests/test_argparse_utils.py:665–699

Test that error() shadows to sys.stderr and uses it for styling.

(mocker: MockerFixture)

def test_parser_error_output_to(mocker: MockerFixture) -> None:
    """Test that error() shadows to sys.stderr and uses it for styling."""
    from cmd2 import rich_utils

    parser = Cmd2ArgumentParser(prog="test")

    # Mock exit to prevent actual exit
    mocker.patch.object(parser, "exit")

    # Mock print_usage to prevent actual printing
    mocker.patch.object(parser, "print_usage")

    # Mock _get_formatter to return a formatter with a mocked console
    mock_formatter = mocker.Mock(spec=rich_utils.Cmd2HelpFormatter)
    mock_console = mocker.MagicMock(spec=rich_utils.Cmd2RichArgparseConsole)
    mock_formatter.console = mock_console

    mocker.patch.object(parser, "_get_formatter", return_value=mock_formatter)

    # Mock capture context manager
    mock_capture = mocker.MagicMock()
    mock_console.capture.return_value.__enter__.return_value = mock_capture
    mock_capture.get.return_value = "Styled Error"

    parser.error("some message")

    # Verify that during error processing, current_output_file was shadowed to sys.stderr
    # Check that print_usage was called with sys.stderr
    parser.print_usage.assert_called_once_with(sys.stderr)  # type: ignore[unreachable]

    # Check that formatter's console was used to print the error
    mock_console.print.assert_called_once()
    args, kwargs = mock_console.print.call_args
    assert "Error: some message" in args[0]
    assert kwargs["style"] == argparse_utils.Cmd2Style.ERROR


def test_parser_implicit_output_to(mocker: MockerFixture) -> None: