Function _screenshot_page

tests/evals/render/render_eval.py:526–570

(
    html_path: Path,
    png_path: Path,
    *,
    timeout_ms: int,
    clip_height: int | None = None,
)

def _screenshot_page(
    html_path: Path,
    png_path: Path,
    *,
    timeout_ms: int,
    clip_height: int | None = None,
) -> None:
    # Hard ceiling so a stalled npx (e.g. cold install) can't hang the run.
    subprocess_timeout = max(timeout_ms / 1000 * 3, 60)
    cmd = [
        "npx",
        "playwright",
        "screenshot",
        "--browser",
        "chromium",
        "--timeout",
        str(timeout_ms),
    ]
    if clip_height is None:
        cmd += ["--full-page", "--viewport-size=1280,900"]
    else:
        # Dropping --full-page makes Playwright capture only the viewport,
        # giving us a top-clipped screenshot that stays under Chromium's
        # full-page capture limits.
        cmd += [f"--viewport-size=1280,{clip_height}"]
    cmd += [html_path.resolve().as_uri(), str(png_path)]
    try:
        result = subprocess.run(
            cmd,
            cwd=REPO_ROOT,
            capture_output=True,
            text=True,
            check=False,
            timeout=subprocess_timeout,
        )
    except subprocess.TimeoutExpired as exc:
        raise RuntimeError(
            f"playwright screenshot timed out after {subprocess_timeout:.0f}s"
        ) from exc
    if result.returncode != 0:
        detail = (result.stderr or result.stdout).strip()
        raise RuntimeError(
            "playwright screenshot failed; run `npx playwright install chromium` "
            f"if browsers are missing. Details: {detail}"
        )


def _screenshot_with_clip_fallback(