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noPlaywrightEval

src/content/docs/linter/rules/no-playwright-eval.mdx

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import { Tabs, TabItem } from '@astrojs/starlight/components';

<Tabs> <TabItem label="JavaScript (and super languages)" icon="seti:javascript"> :::caution This rule is part of the [nursery](/linter/#nursery) group. This means that it is experimental and the behavior can change at any time. ::: ## Summary - Rule available since: `v2.4.2` - Diagnostic Category: [`lint/nursery/noPlaywrightEval`](/reference/diagnostics#diagnostic-category) - This rule doesn't have a fix. - The default severity of this rule is [**information**](/reference/diagnostics#information). - This rule belongs to the following domains: - [`playwright`](/linter/domains#playwright) - Sources: - Same as [`playwright/no-eval`](https://github.com/playwright-community/eslint-plugin-playwright/blob/main/docs/rules/no-eval.md)

How to configure

json
{
	"linter": {
		"rules": {
			"nursery": {
				"noPlaywrightEval": "error"
			}
		}
	}
}

Description

Disallow usage of page.$eval() and page.$$eval().

These methods are discouraged in favor of locator.evaluate() and locator.evaluateAll(). Locator-based evaluation is more reliable and follows Playwright's recommended patterns.

Examples

Invalid

js
await page.$eval('.foo', el => el.textContent);
<pre class="language-text"><code class="language-text">code-block.js:1:7 <a href="https://biomejs.dev/linter/rules/no-playwright-eval">lint/nursery/noPlaywrightEval</a> ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ <strong><span style="color: lightgreen;">ℹ</span></strong> <span style="color: lightgreen;">Unexpected use of </span><span style="color: lightgreen;"><strong>page.$eval()</strong></span><span style="color: lightgreen;">.</span> <strong><span style="color: Tomato;">&gt;</span></strong> <strong>1 │ </strong>await page.$eval('.foo', el =&gt; el.textContent); <strong> │ </strong> <strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong> <strong>2 │ </strong> <strong><span style="color: lightgreen;">ℹ</span></strong> <span style="color: lightgreen;">Locator-based evaluation is more reliable and follows Playwright's recommended patterns.</span> <strong><span style="color: lightgreen;">ℹ</span></strong> <span style="color: lightgreen;">Use </span><span style="color: lightgreen;"><strong>locator.evaluate()</strong></span><span style="color: lightgreen;"> instead.</span> <strong><span style="color: lightgreen;">ℹ</span></strong> <span style="color: lightgreen;">This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit </span><span style="color: lightgreen;"><a href="https://biomejs.dev/linter/#nursery">https://biomejs.dev/linter/#nursery</a></span><span style="color: lightgreen;"> for more information.</span> </code></pre>
js
const texts = await page.$$eval('.foo', els => els.map(el => el.textContent));
<pre class="language-text"><code class="language-text">code-block.js:1:21 <a href="https://biomejs.dev/linter/rules/no-playwright-eval">lint/nursery/noPlaywrightEval</a> ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ <strong><span style="color: lightgreen;">ℹ</span></strong> <span style="color: lightgreen;">Unexpected use of </span><span style="color: lightgreen;"><strong>page.$$eval()</strong></span><span style="color: lightgreen;">.</span> <strong><span style="color: Tomato;">&gt;</span></strong> <strong>1 │ </strong>const texts = await page.$$eval('.foo', els =&gt; els.map(el =&gt; el.textContent)); <strong> │ </strong> <strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong><strong><span style="color: Tomato;">^</span></strong> <strong>2 │ </strong> <strong><span style="color: lightgreen;">ℹ</span></strong> <span style="color: lightgreen;">Locator-based evaluation is more reliable and follows Playwright's recommended patterns.</span> <strong><span style="color: lightgreen;">ℹ</span></strong> <span style="color: lightgreen;">Use </span><span style="color: lightgreen;"><strong>locator.evaluateAll()</strong></span><span style="color: lightgreen;"> instead.</span> <strong><span style="color: lightgreen;">ℹ</span></strong> <span style="color: lightgreen;">This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit </span><span style="color: lightgreen;"><a href="https://biomejs.dev/linter/#nursery">https://biomejs.dev/linter/#nursery</a></span><span style="color: lightgreen;"> for more information.</span> </code></pre>

Valid

js
const text = await page.locator('.foo').evaluate(el => el.textContent);
js
const texts = await page.locator('.foo').evaluateAll(els => els.map(el => el.textContent));
</TabItem> </Tabs>