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How to use assert_to_be_golden method in Playwright Python

Best Python code snippet using playwright-python

test_interception.py

Source:test_interception.py

...572        server.PREFIX,573    )574    img = await page.query_selector("img")575    assert img576    assert_to_be_golden(await img.screenshot(), "mock-binary-response.png")577async def test_request_fulfill_should_allow_mocking_svg_with_charset(578    page, server, assert_to_be_golden579):580    await page.route(581        "**/*",582        lambda route: route.fulfill(583            content_type="image/svg+xml ; charset=utf-8",584            body='<svg width="50" height="50" version="1.1" xmlns="http://www.w3.org/2000/svg"><rect x="10" y="10" width="30" height="30" stroke="black" fill="transparent" stroke-width="5"/></svg>',585        ),586    )587    await page.evaluate(588        """PREFIX => {589      const img = document.createElement('img');590      img.src = PREFIX + '/does-not-exist.svg';591      document.body.appendChild(img);592      return new Promise((f, r) => { img.onload = f; img.onerror = r; });593    }""",594        server.PREFIX,595    )596    img = await page.query_selector("img")597    assert_to_be_golden(await img.screenshot(), "mock-svg.png")598async def test_request_fulfill_should_work_with_file_path(599    page: Page, server, assert_to_be_golden, assetdir600):601    await page.route(602        "**/*",603        lambda route: route.fulfill(604            content_type="shouldBeIgnored", path=assetdir / "pptr.png"605        ),606    )607    await page.evaluate(608        """PREFIX => {609      const img = document.createElement('img');610      img.src = PREFIX + '/does-not-exist.png';611      document.body.appendChild(img);612      return new Promise(fulfill => img.onload = fulfill);613    }""",614        server.PREFIX,615    )616    img = await page.query_selector("img")617    assert img618    assert_to_be_golden(await img.screenshot(), "mock-binary-response.png")619async def test_request_fulfill_should_stringify_intercepted_request_response_headers(620    page, server621):622    await page.route(623        "**/*",624        lambda route: route.fulfill(625            status=200, headers={"foo": True}, body="Yo, page!"626        ),627    )628    response = await page.goto(server.EMPTY_PAGE)629    assert response.status == 200630    headers = response.headers631    assert headers["foo"] == "True"632    assert await page.evaluate("() => document.body.textContent") == "Yo, page!"...

test_locators.py

Source:test_locators.py

...287    )288    page.goto(server.PREFIX + "/grid.html")289    page.evaluate("window.scrollBy(50, 100)")290    element = page.locator(".box:nth-of-type(3)")291    assert_to_be_golden(element.screenshot(), "screenshot-element-bounding-box.png")292def test_locators_should_return_bounding_box(page: Page, server: Server) -> None:293    page.set_viewport_size(294        {295            "width": 500,296            "height": 500,297        }298    )299    page.goto(server.PREFIX + "/grid.html")300    element = page.locator(".box:nth-of-type(13)")301    box = element.bounding_box()302    assert box == {303        "x": 100,304        "y": 50,305        "width": 50,...

test_emulation_focus.py

Source:test_emulation_focus.py

...98    screenshots = await asyncio.gather(99        page.screenshot(),100        page2.screenshot(),101    )102    assert_to_be_golden(screenshots[0], "screenshot-sanity.png")103    assert_to_be_golden(screenshots[1], "grid-cell-0.png")104async def test_should_change_focused_iframe(page, server, utils):105    await page.goto(server.EMPTY_PAGE)106    [frame1, frame2] = await asyncio.gather(107        utils.attach_frame(page, "frame1", server.PREFIX + "/input/textarea.html"),108        utils.attach_frame(page, "frame2", server.PREFIX + "/input/textarea.html"),109    )110    logger = """() => {111        self._events = [];112        const element = document.querySelector('input');113        element.onfocus = element.onblur = (e) => self._events.push(e.type);114    }"""115    await asyncio.gather(116        frame1.evaluate(logger),117        frame2.evaluate(logger),...

conftest.py

Source:conftest.py

...117        default=False,118        help="Run tests in headful mode.",119    )120@pytest.fixture(scope="session")121def assert_to_be_golden(browser_name: str):122    def compare(received_raw: bytes, golden_name: str):123        golden_file = (_dirname / f"golden-{browser_name}" / golden_name).read_bytes()124        received_image = Image.open(io.BytesIO(received_raw))125        golden_image = Image.open(io.BytesIO(golden_file))126        if golden_image.size != received_image.size:127            pytest.fail("Image size differs to golden image")128            return129        diff_pixels = pixelmatch(130            from_PIL_to_raw_data(received_image),131            from_PIL_to_raw_data(golden_image),132            golden_image.size[0],133            golden_image.size[1],134            threshold=0.2,135        )...

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