Skip to content

Latest commit

 

History

History
825 lines (666 loc) · 25.7 KB

selectors.md

File metadata and controls

825 lines (666 loc) · 25.7 KB
id title
selectors
Element selectors

Selectors are strings that point to the elements in the page. They are used to perform actions on those elements by means of methods such as [method: Page.click], [method: Page.fill] and alike. All those methods accept [param: selector] as their first argument.

Quick guide

  • Text selector
    await page.click('text=Log in');
    page.click("text=Log in");
    await page.click("text=Log in")
    page.click("text=Log in")
    Learn more about text selector.
  • CSS selector
    await page.click('button');
    await page.click('#nav-bar .contact-us-item');
    page.click("button");
    page.click("#nav-bar .contact-us-item");
    await page.click("button")
    await page.click("#nav-bar .contact-us-item")
    page.click("button")
    page.click("#nav-bar .contact-us-item")
    Learn more about css selector.
  • Select by attribute, with css selector
    await page.click('[data-test=login-button]');
    await page.click('[aria-label="Sign in"]');
    page.click("[data-test=login-button]");
    page.click("[aria-label='Sign in']");
    await page.click("[data-test=login-button]")
    await page.click("[aria-label='Sign in']")
    page.click("[data-test=login-button]")
    page.click("[aria-label='Sign in']")
    Learn more about css selector.
  • Combine css and text selectors
    await page.click('article:has-text("Playwright")');
    await page.click('#nav-bar :text("Contact us")');
    page.click("article:has-text(\"Playwright\")");
    page.click("#nav-bar :text(\"Contact us\")");
    await page.click("article:has-text('Playwright')")
    await page.click("#nav-bar :text('Contact us')")
    page.click("article:has-text('Playwright')")
    page.click("#nav-bar :text('Contact us')")
    Learn more about :has-text() and :text() pseudo classes.
  • Element that contains another, with css selector
    await page.click('.item-description:has(.item-promo-banner)');
    page.click(".item-description:has(.item-promo-banner)");
    await page.click(".item-description:has(.item-promo-banner)")
    page.click(".item-description:has(.item-promo-banner)")
    Learn more about :has() pseudo class.
  • Selecting based on layout, with css selector
    await page.click('input:right-of(:text("Username"))');
    page.click("input:right-of(:text(\"Username\"))");
    await page.click("input:right-of(:text('Username'))")
    page.click("input:right-of(:text('Username'))")
    Learn more about layout selectors.
  • Only visible elements, with css selector
    await page.click('.login-button:visible');
    page.click(".login-button:visible");
    await page.click(".login-button:visible")
    page.click(".login-button:visible")
    Learn more about :visible pseudo-class.
  • Pick n-th match
    await page.click(':nth-match(:text("Buy"), 3)');
    page.click(":nth-match(:text('Buy'), 3)");
    await page.click(":nth-match(:text('Buy'), 3)"
    page.click(":nth-match(:text('Buy'), 3)"
    Learn more about :nth-match() pseudo-class.
  • XPath selector
    await page.click('xpath=//button');
    page.click("xpath=//button");
    await page.click("xpath=//button")
    page.click("xpath=//button")
    Learn more about XPath selector.

Text selector

Text selector locates elements that contain passed text.

await page.click('text=Log in');
page.click("text=Log in");
await page.click("text=Log in")
page.click("text=Log in")

Text selector has a few variations:

  • text=Log in - default matching is case-insensitive and searches for a substring. For example, text=Log matches <button>Log in</button>.

    await page.click('text=Log in');
    page.click("text=Log in");
    await page.click("text=Log in")
    page.click("text=Log in")
  • text="Log in" - text body can be escaped with single or double quotes to search for a text node with exact content. For example, text="Log" does not match <button>Log in</button> because <button> contains a single text node "Log in" that is not equal to "Log". However, text="Log" matches <button>Log<span>in</span></button>, because <button> contains a text node "Log".

    Quoted body follows the usual escaping rules, e.g. use \" to escape double quote in a double-quoted string: text="foo\"bar".

    await page.click('text="Log in"');
    page.click("text='Log in'");
    await page.click("text='Log in'")
    page.click("text='Log in'")
  • "Log in" - selector starting and ending with a quote (either " or ') is assumed to be a text selector. For example, "Log in" is converted to text="Log in" internally.

    await page.click('"Log in"');
    page.click("'Log in'");
    await page.click("'Log in'")
    page.click("'Log in'")
  • /Log\s*in/i - body can be a JavaScript-like regex wrapped in / symbols. For example, text=/Log\s*in/i matches <button>Login</button> and <button>log IN</button>.

    await page.click('text=/Log\\s*in/i');
    page.click("text=/Log\\s*in/i");
    await page.click("text=/Log\s*in/i")
    page.click("text=/Log\s*in/i")
  • article:has-text("Playwright") - the :has-text() pseudo-class can be used inside a css selector. It matches any element containing specified text somewhere inside, possibly in a child or a descendant element. For example, article:has-text("Playwright") matches <article><div>Playwright</div></article>.

    Note that :has-text() should be used together with other css specifiers, otherwise it will match all the elements containing specified text, including the <body>.

    // Wrong, will match many elements including <body>
    await page.click(':has-text("Playwright")');
    // Correct, only matches the <article> element
    await page.click('article:has-text("Playwright")');
    // Wrong, will match many elements including <body>
    page.click(":has-text(\"Playwright\")");
    // Correct, only matches the <article> element
    page.click("article:has-text(\"Playwright\")");
    # Wrong, will match many elements including <body>
    await page.click(':has-text("Playwright")')
    # Correct, only matches the <article> element
    await page.click('article:has-text("Playwright")')
    # Wrong, will match many elements including <body>
    page.click(':has-text("Playwright")')
    # Correct, only matches the <article> element
    page.click('article:has-text("All products")')
  • #nav-bar :text("Home") - the :text() pseudo-class can be used inside a css selector. It matches the smallest element containing specified text. This example is equivalent to text=Home, but inside the #nav-bar element.

    await page.click('#nav-bar :text("Home")');
    page.click("#nav-bar :text('Home')");
    await page.click("#nav-bar :text('Home')")
    page.click("#nav-bar :text('Home')")
  • #nav-bar :text-is("Home") - the :text-is() pseudo-class can be used inside a css selector, for strict text node match. This example is equivalent to text="Home" (note quotes), but inside the #nav-bar element.

  • #nav-bar :text-matches("reg?ex", "i") - the :text-matches() pseudo-class can be used inside a css selector, for regex-based match. This example is equivalent to text=/reg?ex/i, but inside the #nav-bar element.

:::note Matching always normalizes whitespace, for example it turns multiple spaces into one, turns line breaks into spaces and ignores leading and trailing whitespace. :::

:::note Input elements of the type button and submit are matched by their value instead of text content. For example, text=Log in matches <input type=button value="Log in">. :::

CSS selector

Playwright augments standard CSS selectors in two ways:

  • css engine pierces open shadow DOM by default.
  • Playwright adds custom pseudo-classes like :visible, :text and more.
await page.click('button');
page.click("button");
await page.click("button")
page.click("button")

Selecting visible elements

The :visible pseudo-class in CSS selectors matches the elements that are visible. 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.

:::note It's usually better to follow the best practices and find a more reliable way to uniquely identify the element. :::

Consider a page with two buttons, first invisible and second visible.

<button style='display: none'>Invisible</button>
<button>Visible</button>
  • This will find the first button, because it is the first one in DOM order. Then it will wait for the button to become visible before clicking, or timeout while waiting:

    await page.click('button');
    page.click("button");
    await page.click("button")
    page.click("button")
  • This will find a second button, because it is visible, and then click it.

    await page.click('button:visible');
    page.click("button:visible");
    await page.click("button:visible")
    page.click("button:visible")

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

  • When elements change their visibility dynamically, :visible will give unpredictable 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.

Selecting elements that contain other elements

The :has() pseudo-class is an experimental CSS pseudo-class. It returns an element if any of the selectors passed as parameters relative to the :scope of the given element match at least one element.

Following snippet returns text content of an <article> element that has a <div class=promo> inside.

await page.textContent('article:has(div.promo)');
page.textContent("article:has(div.promo)");
await page.textContent("article:has(div.promo)")
page.textContent("article:has(div.promo)")

Selecting elements matching one of the conditions

The :is() pseudo-class is an experimental CSS pseudo-class. It is a function that takes a selector list as its argument, and selects any element that can be selected by one of the selectors in that list. This is useful for writing large selectors in a more compact form.

// Clicks a <button> that has either a "Log in" or "Sign in" text.
await page.click(':is(button:has-text("Log in"), button:has-text("Sign in"))');
// Clicks a <button> that has either a "Log in" or "Sign in" text.
page.click(":is(button:has-text(\"Log in\"), button:has-text(\"Sign in\"))");
# Clicks a <button> that has either a "Log in" or "Sign in" text.
await page.click(':is(button:has-text("Log in"), button:has-text("Sign in"))')
# Clicks a <button> that has either a "Log in" or "Sign in" text.
page.click(':is(button:has-text("Log in"), button:has-text("Sign in"))')

Selecting elements in Shadow DOM

Our css and text engines pierce the Shadow DOM by default:

  • First they search for the elements in the light DOM in the iteration order, and
  • Then they search recursively inside open shadow roots in the iteration order.

In particular, in css engine, 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. It does not search inside closed shadow roots or iframes.

If you'd like to opt-out of this behavior, you can use :light CSS extension or text:light selector engine. They do not pierce shadow roots.

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

More advanced Shadow DOM use cases:

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

Selecting elements based on layout

Playwright can select elements based on the page layout. These can be combined with regular CSS for better results, for example input:right-of(:text("Password")) matches an input field that is to the right of text "Password".

:::note Layout selectors depend on the page layout and may produce unexpected results. For example, a different element could be matched when layout changes by one pixel. :::

Layout selectors use bounding client rect to compute distance and relative position of the elements.

  • :right-of(inner > selector) - Matches elements that are to the right of any element matching the inner selector.
  • :left-of(inner > selector) - Matches elements that are to the left of any element matching the inner selector.
  • :above(inner > selector) - Matches elements that are above any of the elements matching the inner selector.
  • :below(inner > selector) - Matches elements that are below any of the elements matching the inner selector.
  • :near(inner > selector) - Matches elements that are near (within 50 CSS pixels) any of the elements matching the inner selector.
// Fill an input to the right of "Username".
await page.fill('input:right-of(:text("Username"))', 'value');

// Click a button near the promo card.
await page.click('button:near(.promo-card)');
// Fill an input to the right of "Username".
page.fill("input:right-of(:text(\"Username\"))", "value");

// Click a button near the promo card.
page.click("button:near(.promo-card)");
# Fill an input to the right of "Username".
await page.fill('input:right-of(:text("Username"))', 'value')

# Click a button near the promo card.
await page.click('button:near(.promo-card)')
# Fill an input to the right of "Username".
page.fill('input:right-of(:text("Username"))', 'value')

# Click a button near the promo card.
page.click('button:near(.promo-card)')

XPath selectors

XPath selectors are equivalent to calling Document.evaluate. Example: xpath=//html/body.

Selector starting with // or .. is assumed to be an xpath selector. For example, Playwright converts '//html/body' to 'xpath=//html/body'.

:::note xpath does not pierce shadow roots :::

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

Playwright supports a shorthand for selecting elements using certain attributes. Currently, only the following attributes are supported:

  • id
  • data-testid
  • data-test-id
  • data-test
// Fill an input with the id "username"
await page.fill('id=username', 'value');

// Click an element with data-test-id "submit"
await page.click('data-test-id=submit');
// Fill an input with the id "username"
page.fill("id=username", "value");

// Click an element with data-test-id "submit"
page.click("data-test-id=submit");
# Fill an input with the id "username"
await page.fill('id=username', 'value')

# Click an element with data-test-id "submit"
await page.click('data-test-id=submit')
# Fill an input with the id "username"
page.fill('id=username', 'value')

# Click an element with data-test-id "submit"
page.click('data-test-id=submit')

:::note Attribute selectors pierce shadow DOM. To opt-out from this behavior, use :light suffix after attribute, for example `page.click('data-test-id:light=submit') :::

Pick n-th match from the query result

Sometimes page contains a number of similar elements, and it is hard to select a particular one. For example:

<section> <button>Buy</button> </section>
<article><div> <button>Buy</button> </div></article>
<div><div> <button>Buy</button> </div></div>

In this case, :nth-match(:text("Buy"), 3) will select the third button from the snippet above. Note that index is one-based.

// Click the third "Buy" button
await page.click(':nth-match(:text("Buy"), 3)');
// Click the third "Buy" button
page.click(":nth-match(:text('Buy'), 3)");
# Click the third "Buy" button
await page.click(":nth-match(:text('Buy'), 3)"
# Click the third "Buy" button
page.click(":nth-match(:text('Buy'), 3)"

:nth-match() is also useful to wait until a specified number of elements appear, using [method: Page.waitForSelector].

// Wait until all three buttons are visible
await page.waitForSelector(':nth-match(:text("Buy"), 3)');
// Wait until all three buttons are visible
page.waitForSelector(":nth-match(:text('Buy'), 3)");
# Wait until all three buttons are visible
await page.wait_for_selector(":nth-match(:text('Buy'), 3)")
# Wait until all three buttons are visible
page.wait_for_selector(":nth-match(:text('Buy'), 3)")

:::note Unlike :nth-child(), elements do not have to be siblings, they could be anywhere on the page. In the snippet above, all three buttons match :text("Buy") selector, and :nth-match() selects the third button. :::

:::note It is usually possible to distinguish elements by some attribute or text content. In this case, prefer using text or css selectors over the :nth-match(). :::

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"]', 'query');
await page.fill('[placeholder="Search GitHub"]', 'query'); // 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');
// queries "Login" text selector
page.click("text=\"Login\"");
page.click("\"Login\""); // short-form

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

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

// combine role and text queries
page.click("css=nav >> text=Login");
# 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"]', 'query')
await page.fill('[placeholder="Search GitHub"]', 'query') # 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')
# queries "Login" text selector
page.click('text="Login"')
page.click('"Login"') # short-form

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

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

# combine role and text queries
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');
// queries data-test-id attribute with css
page.click("css=[data-test-id=directions]");
page.click("[data-test-id=directions]"); // short-form

// queries data-test-id with id
page.click("data-test-id=directions");
# 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')
# queries data-test-id attribute with css
page.click('css=[data-test-id=directions]')
page.click('[data-test-id=directions]') # short-form

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