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Element selectors

Selectors query elements on the web page for interactions, like page.click, and to obtain ElementHandle through page.$. Built-in selectors auto-pierce shadow DOM.

Syntax

Selectors are defined by selector engine name and selector body, engine=body.

Body format is assumed to ignore leading and trailing white spaces, so that extra whitespace can be added for readability.

Short-forms

For convenience, common selectors have short-forms:

  • Selector starting with // or .. is assumed to be xpath=selector
    • Example: page.click('//html') is converted to page.click('xpath=//html').
  • Selector starting and ending with a quote (either " or ') is assumed to be text=selector
    • Example: page.click('"foo"') is converted to page.click('text="foo"').
  • Otherwise, selector is assumed to be css=selector
    • Example: page.click('div') is converted to page.click('css=div').

Chaining selectors

Selectors defined as engine=body or in short-form can be combined with the >> token, e.g. selector1 >> selector2 >> selectors3. When selectors are chained, next one is queried relative to the previous one's result.

For example,

css=article >> css=.bar > .baz >> css=span[attr=value]

is equivalent to

document
  .querySelector('article')
  .querySelector('.bar > .baz')
  .querySelector('span[attr=value]')

If a selector needs to include >> in the body, it should be escaped inside a string to not be confused with chaining separator, e.g. text="some >> text".

Intermediate matches

By default, chained selectors resolve to an element queried by the last selector. A selector can be prefixed with * to capture elements that are queried by an intermediate selector.

For example, css=article >> text=Hello captures the element with the text Hello, and *css=article >> text=Hello (note the *) captures the article element that contains some element with the text Hello.

Best practices

The choice of selectors determines the resiliency of automation scripts. To reduce the maintenance burden, we recommend prioritizing user-facing attributes and explicit contracts.

Prioritize user-facing attributes

Attributes like text content, input placeholder, accessibility roles and labels are user-facing attributes that change rarely. These attributes are not impacted by DOM structure changes.

The following examples use the built-in text and css selector engines.

// queries "Login" text selector
await page.click('text="Login"');
await page.click('"Login"'); // short-form

// queries "Search GitHub" placeholder attribute
await page.fill('css=[placeholder="Search GitHub"]');
await page.fill('[placeholder="Search GitHub"]'); // short-form

// queries "Close" accessibility label
await page.click('css=[aria-label="Close"]');
await page.click('[aria-label="Close"]'); // short-form

// combine role and text queries
await page.click('css=nav >> text=Login');

Define explicit contract

When user-facing attributes change frequently, it is recommended to use explicit test ids, like data-test-id. These data-* attributes are supported by the css and id selectors.

<button data-test-id="directions">Itinéraire</button>
// queries data-test-id attribute with css
await page.click('css=[data-test-id=directions]');
await page.click('[data-test-id=directions]'); // short-form

// queries data-test-id with id
await page.click('data-test-id=directions');

Avoid selectors tied to implementation

xpath and css can be tied to the DOM structure or implementation. These selectors can break when the DOM structure changes.

// avoid long css or xpath chains
await page.click('#tsf > div:nth-child(2) > div.A8SBwf > div.RNNXgb > div > div.a4bIc > input');
await page.click('//*[@id="tsf"]/div[2]/div[1]/div[1]/div/div[2]/input');

Examples

// queries 'div' css selector
const handle = await page.$('css=div');

// queries '//html/body/div' xpath selector
const handle = await page.$('xpath=//html/body/div');

// queries '"foo"' text selector
const handle = await page.$('text="foo"');

// queries 'span' css selector inside the result of '//html/body/div' xpath selector
const handle = await page.$('xpath=//html/body/div >> css=span');

// converted to 'css=div'
const handle = await page.$('div');

// converted to 'xpath=//html/body/div'
const handle = await page.$('//html/body/div');

// converted to 'text="foo"'
const handle = await page.$('"foo"');

// queries 'span' css selector inside the div handle
const handle = await divHandle.$('css=span');

Selector engines

css and css:light

css is a default engine - any malformed selector not starting with // nor starting and ending with a quote is assumed to be a css selector. For example, Playwright converts page.$('span > button') to page.$('css=span > button').

Playwright augments standard CSS selectors in two ways, see below for more details:

  • css engine pierces open shadow DOM by default.
  • Playwright adds a few custom pseudo-classes like :visible.

Shadow piercing

css:light engine is equivalent to Document.querySelector and behaves according to the CSS spec. However, it does not pierce shadow roots, which may be inconvenient when working with Shadow DOM and Web Components. For that reason, css engine pierces shadow roots. More specifically, any Descendant combinator or Child combinator pierces an arbitrary number of open shadow roots, including the implicit descendant combinator at the start of the selector.

css engine first searches for elements in the light dom in the iteration order, and then recursively inside open shadow roots in the iteration order. It does not search inside closed shadow roots or iframes.

<article>
  <div>In the light dom</div>
  <div slot='myslot'>In the light dom, but goes into the shadow slot</div>
  <open mode shadow root>
    <div class='in-the-shadow'>
      <span class='content'>
        In the shadow dom
        <open mode shadow root>
          <li id='target'>Deep in the shadow</li>
        </open mode shadow root>
      </span>
    </div>
    <slot name='myslot'></slot>
  </open mode shadow root>
</article>

Note that <open mode shadow root> is not an html element, but rather a shadow root created with element.attachShadow({mode: 'open'}).

  • Both "css=article div" and "css:light=article div" match the first <div>In the light dom</div>.
  • Both "css=article > div" and "css:light=article > div" match two div elements that are direct children of the article.
  • "css=article .in-the-shadow" matches the <div class='in-the-shadow'>, piercing the shadow root, while "css:light=article .in-the-shadow" does not match anything.
  • "css:light=article div > span" does not match anything, because both light-dom div elements do not contain a span.
  • "css=article div > span" matches the <span class='content'>, piercing the shadow root.
  • "css=article > .in-the-shadow" does not match anything, because <div class='in-the-shadow'> is not a direct child of article
  • "css:light=article > .in-the-shadow" does not match anything.
  • "css=article li#target" matches the <li id='target'>Deep in the shadow</li>, piercing two shadow roots.

CSS extension: visible

The :visible pseudo-class matches elements that are visible as defined in the actionability guide. For example, input matches all the inputs on the page, while input:visible matches only visible inputs. This is useful to distinguish elements that are very similar but differ in visibility.

// Clicks the first button.
await page.click('button');
// Clicks the first visible button. If there are some invisible buttons, this click will just ignore them.
await page.click('button:visible');

Use :visible with caution, because it has two major drawbacks:

  • When elements change their visibility dynamically, :visible will give upredictable results based on the timing.
  • :visible forces a layout and may lead to querying being slow, especially when used with page.waitForSelector(selector[, options]) method.

CSS extension: text

The :text pseudo-class matches elements that have a text node child with specific text. It is similar to the text engine. There are a few variations that support different arguments:

  • :text("substring") - Matches when element's text contains "substring" somewhere. Matching is case-insensitive. Matching also normalizes whitespace, for example it turns multiple spaces into one, trusn line breaks into spaces and ignores leading and trailing whitespace.
  • :text-is("string") - Matches when element's text equals the "string". Matching is case-insensitive and normalizes whitespace.
  • button:text("Sign in") - Text selector may be combined with regular CSS.
  • :text-matches("[+-]?\\d+") - Matches text against a regular expression. Note that special characters like back-slash \, quotes ", square brackets [] and more should be escaped. Learn more about regular expressions.
  • :text-matches("value", "i") - Matches text against a regular expression with specified flags.
// Click a button with text "Sign in".
await page.click('button:text("Sign in")');

CSS extension: light

css engine pierces shadow by default. It is possible to disable this behavior by wrapping a selector in :light pseudo-class: :light(section > button.class) matches in light DOM only.

await page.click(':light(.article > .header)');

xpath

XPath engine is equivalent to Document.evaluate. Example: xpath=//html/body.

Malformed selector starting with // or .. is assumed to be an xpath selector. For example, Playwright converts page.$('//html/body') to page.$('xpath=//html/body').

Note that xpath does not pierce shadow roots.

text and text:light

Text engine finds an element that contains a text node with the passed text. For example, page.click('text=Login') clicks on a login button, and page.waitForSelector('"lazy loaded text") waits for the "lazy loaded text" to appear in the page.

  • By default, the match is case-insensitive, ignores leading/trailing whitespace and searches for a substring. This means text= Login matches <button>Button loGIN (click me)</button>.
  • Text body can be escaped with single or double quotes for precise matching, insisting on exact match, including specified whitespace and case. This means text="Login " will only match <button>Login </button> with exactly one space after "Login". Quoted text follows the usual escaping rules, e.g. use \" to escape double quote in a double-quoted string: text="foo\"bar".
  • Text body can also be a JavaScript-like regex wrapped in / symbols. This means text=/^\\s*Login$/i will match <button> loGIN</button> with any number of spaces before "Login" and no spaces after.
  • Input elements of the type button and submit are rendered with their value as text, and text engine finds them. For example, text=Login matches <input type=button value="Login">.

Malformed selector starting and ending with a quote (either " or ') is assumed to be a text selector. For example, Playwright converts page.click('"Login"') to page.click('text="Login"').

text engine open pierces shadow roots similarly to css, while text:light does not. Text engine first searches for elements in the light dom in the iteration order, and then recursively inside open shadow roots in the iteration order. It does not search inside closed shadow roots or iframes.

id, data-testid, data-test-id, data-test and their :light counterparts

Attribute engines are selecting based on the corresponding attribute value. For example: data-test-id=foo is equivalent to css=[data-test-id="foo"], and id:light=foo is equivalent to css:light=[id="foo"].