Function test_dirty_cache

tests/test_styles_cache.py:193–271

Check that we only render content once or if it has been marked as dirty.

()

def test_dirty_cache() -> None:
    """Check that we only render content once or if it has been marked as dirty."""

    content = [
        Strip([Segment("foo")]),
        Strip([Segment("bar")]),
        Strip([Segment("baz")]),
    ]
    rendered_lines: list[int] = []

    def get_content_line(y: int) -> Strip:
        rendered_lines.append(y)
        return content[y]

    styles = Styles()
    styles.padding = 1
    styles.border = ("heavy", "white")
    cache = StylesCache()
    lines = cache.render(
        styles,
        Size(7, 7),
        Color.parse("blue"),
        Color.parse("green"),
        get_content_line,
        [],
        None,
        None,
        content_size=Size(3, 3),
    )
    assert rendered_lines == [0, 1, 2]
    del rendered_lines[:]

    text_content = _extract_content(lines)

    expected_text = [
        "┏━━━━━┓",
        "┃     ┃",
        "┃ foo ┃",
        "┃ bar ┃",
        "┃ baz ┃",
        "┃     ┃",
        "┗━━━━━┛",
    ]
    assert text_content == expected_text

    # Re-render styles, check that content was not requested
    lines = cache.render(
        styles,
        Size(7, 7),
        Color.parse("blue"),
        Color.parse("green"),
        get_content_line,
        [],
        None,
        None,
        content_size=Size(3, 3),
    )
    assert rendered_lines == []