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How to use register_selector_engine method in Playwright Python

Best Python code snippet using playwright-python

test_dispatch_event.py

Source:test_dispatch_event.py

...93    )94    await watchdog95    assert await page.evaluate("() => window.clicked")96async def test_should_be_atomic(selectors, page, utils):97    await utils.register_selector_engine(98        selectors,99        "dispatch_event",100        """{101            create(root, target) { },102            query(root, selector) {103                const result = root.querySelector(selector);104                if (result)105                Promise.resolve().then(() => result.onclick = "");106                return result;107            },108            queryAll(root, selector) {109                const result = Array.from(root.query_selector_all(selector));110                for (const e of result)111                Promise.resolve().then(() => result.onclick = "");...

test_queryselector.py

Source:test_queryselector.py

...33    await context.close()34async def test_selectors_register_should_work_with_path(35    selectors, page: Page, utils, assetdir36):37    await utils.register_selector_engine(38        selectors, "foo", path=assetdir / "sectionselectorengine.js"39    )40    await page.set_content("<section></section>")41    assert await page.eval_on_selector("foo=whatever", "e => e.nodeName") == "SECTION"42async def test_selectors_register_should_work_in_main_and_isolated_world(43    selectors, page: Page, utils44):45    dummy_selector_script = """{46      create(root, target) { },47      query(root, selector) {48        return window.__answer;49      },50      queryAll(root, selector) {51        return window['__answer'] ? [window['__answer'], document.body, document.documentElement] : [];52      }53    }"""54    await utils.register_selector_engine(selectors, "main", dummy_selector_script)55    await utils.register_selector_engine(56        selectors, "isolated", dummy_selector_script, content_script=True57    )58    await page.set_content("<div><span><section></section></span></div>")59    await page.evaluate('() => window.__answer = document.querySelector("span")')60    # Works in main if asked.61    assert await page.eval_on_selector("main=ignored", "e => e.nodeName") == "SPAN"62    assert (63        await page.eval_on_selector("css=div >> main=ignored", "e => e.nodeName")64        == "SPAN"65    )66    assert await page.eval_on_selector_all(67        "main=ignored", "es => window.__answer !== undefined"68    )69    assert (70        await page.eval_on_selector_all(71            "main=ignored", "es => es.filter(e => e).length"72        )73        == 374    )75    # Works in isolated by default.76    assert await page.query_selector("isolated=ignored") is None77    assert await page.query_selector("css=div >> isolated=ignored") is None78    # $$eval always works in main, to avoid adopting nodes one by one.79    assert await page.eval_on_selector_all(80        "isolated=ignored", "es => window.__answer !== undefined"81    )82    assert (83        await page.eval_on_selector_all(84            "isolated=ignored", "es => es.filter(e => e).length"85        )86        == 387    )88    # At least one engine in main forces all to be in main.89    assert (90        await page.eval_on_selector(91            "main=ignored >> isolated=ignored", "e => e.nodeName"92        )93        == "SPAN"94    )95    assert (96        await page.eval_on_selector(97            "isolated=ignored >> main=ignored", "e => e.nodeName"98        )99        == "SPAN"100    )101    # Can be chained to css.102    assert (103        await page.eval_on_selector("main=ignored >> css=section", "e => e.nodeName")104        == "SECTION"105    )106async def test_selectors_register_should_handle_errors(selectors, page: Page, utils):107    with pytest.raises(Error) as exc:108        await page.query_selector("neverregister=ignored")109    assert (110        'Unknown engine "neverregister" while parsing selector neverregister=ignored'111        in exc.value.message112    )113    dummy_selector_engine_script = """{114      create(root, target) {115        return target.nodeName;116      },117      query(root, selector) {118        return root.querySelector('dummy');119      },120      queryAll(root, selector) {121        return Array.from(root.query_selector_all('dummy'));122      }123    }"""124    with pytest.raises(Error) as exc:125        await selectors.register("$", dummy_selector_engine_script)126    assert (127        exc.value.message128        == "Selector engine name may only contain [a-zA-Z0-9_] characters"129    )130    # Selector names are case-sensitive.131    await utils.register_selector_engine(132        selectors, "dummy", dummy_selector_engine_script133    )134    await utils.register_selector_engine(135        selectors, "duMMy", dummy_selector_engine_script136    )137    with pytest.raises(Error) as exc:138        await selectors.register("dummy", dummy_selector_engine_script)139    assert exc.value.message == '"dummy" selector engine has been already registered'140    with pytest.raises(Error) as exc:141        await selectors.register("css", dummy_selector_engine_script)...

utils.py

Source:utils.py

...55        assert cast(ViewportSize, page.viewport_size)["width"] == width56        assert cast(ViewportSize, page.viewport_size)["height"] == height57        assert page.evaluate("window.innerWidth") == width58        assert page.evaluate("window.innerHeight") == height59    def register_selector_engine(self, selectors: Selectors, *args, **kwargs) -> None:60        try:61            selectors.register(*args, **kwargs)62        except Error as exc:63            if "has been already registered" not in exc.message:64                raise exc...

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