Selector engines

Playwright supports multiple selector engines used to query elements in the web page.

Selector can be used to obtain ElementHandle (see page.$() for example) or shortcut element operations to avoid intermediate handle (see page.click() for example).

Selector syntax

Selector is a string that consists of one or more clauses separated by >> token, e.g. clause1 >> clause2 >> clause3. When multiple clauses are present, next one is queried relative to the previous one's result.

Each clause contains a selector engine name and selector body, e.g. engine=body. Here engine is one of the supported engines (e.g. css or a custom one). Selector body follows the format of the particular engine, e.g. for css engine it should be a css selector. Body format is assumed to ignore leading and trailing whitespaces, so that extra whitespace can be added for readability. If selector engine needs to include >> in the body, it should be escaped inside a string to not be confused with clause separator, e.g. text="some >> text".

For example,

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

is equivalent to

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

For convenience, selectors in the wrong format are heuristically converted to the right format:

Selector starting with // is assumed to be xpath=selector. Example: page.click('//html') is converted to page.click('xpath=//html').
Selector starting with " 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').

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');

Built-in selector engines

css

CSS engine is equivalent to Document.querySelector. Example: css=.article > span:nth-child(2) li.

Note

Malformed selector not starting with // nor with # is automatically transformed to css selector. For example, Playwright converts page.$('span > button') to page.$('css=span > button'). Selectors starting with # are converted to text. Selectors starting with // are converted to xpath.

xpath

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

Note

Malformed selector starting with // is automatically transformed to xpath selector. For example, Playwright converts page.$('//html/body') to page.$('xpath=//html/body').

text

Text engine finds an element that contains a text node with passed text. Example: text=Login.

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 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".
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.

Note

Malformed selector starting with " is automatically transformed to text selector. For example, Playwright converts page.click('"Login"') to page.click('text="Login"').

id, data-testid, data-test-id, data-test

Id engines are selecting based on the corresponding atrribute value. For example: data-test-id=foo is equivalent to querySelector('*[data-test-id=foo]').

Custom selector engines

Playwright supports custom selector engines, registered with selectors.register(name, script[, options]).

Selector engine should have the following properties:

create Function to create a relative selector from root (root is either a Document, ShadowRoot or Element) to a target element.
query Function to query first element matching selector relative to the root.
queryAll Function to query all elements matching selector relative to the root.

By default the engine is run directly in the frame's JavaScript context and, for example, can call an application-defined function. To isolate the engine from any JavaScript in the frame, but leave access to the DOM, resgister the engine with {contentScript: true} option. Content script engine is safer because it is protected from any tampering with the global objects, for example altering Node.prototype methods. All built-in selector engines run as content scripts. Note that running as a content script is not guaranteed when the engine is used together with other custom engines.

An example of registering selector engine that queries elements based on a tag name:

// Must be a function that evaluates to a selector engine instance.
const createTagNameEngine = () => ({
  // Creates a selector that matches given target when queried at the root.
  // Can return undefined if unable to create one.
  create(root, target) {
    return root.querySelector(target.tagName) === target ? target.tagName : undefined;
  },

  // Returns the first element matching given selector in the root's subtree.
  query(root, selector) {
    return root.querySelector(selector);
  },

  // Returns all elements matching given selector in the root's subtree.
  queryAll(root, selector) {
    return Array.from(root.querySelectorAll(selector));
  }
});

// Register the engine. Selectors will be prefixed with "tag=".
await selectors.register('tag', createTagNameEngine);

// Now we can use 'tag=' selectors.
const button = await page.$('tag=button');

// We can combine it with other selector engines.
await page.click('tag=div >> text="Click me"');

// We can use it in any methods supporting selectors.
const buttonCount = await page.$$eval('tag=button', buttons => buttons.length);

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