| <!DOCTYPE html> |
| <html> |
| <head> |
| <meta charset="utf-8"> |
| <title>CSS Selectors Invalidation: :first-child :last-child</title> |
| <link rel="help" href="https://drafts.csswg.org/selectors-4/#the-first-child-pseudo"> |
| <meta name="assert" content="This tests that the :first-child and :last-child selectors are effective"> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <style> |
| div { |
| color: black; |
| } |
| span:first-child { |
| color: blue; |
| } |
| span:last-child { |
| color: red; |
| } |
| </style> |
| </head> |
| <body> |
| <div id="target"><span>first-initially</span><span>last-initially</span></div> |
| <script> |
| |
| 'use strict'; |
| const black = 'rgb(0, 0, 0)'; |
| const blue = 'rgb(0, 0, 255)'; |
| const red = 'rgb(255, 0, 0)'; |
| |
| test(() => { |
| const target = document.querySelector('#target'); |
| const first = target.firstChild; |
| assert_equals(getComputedStyle(first).color, blue); |
| target.insertAdjacentHTML('afterbegin', '\n<span>foo</span><span>bar</span>'); |
| assert_equals(getComputedStyle(target.firstElementChild).color, blue); |
| assert_equals(getComputedStyle(first).color, black); |
| while (target.firstElementChild !== first) |
| target.removeChild(target.firstElementChild); |
| assert_equals(getComputedStyle(first).color, blue); |
| }, 'Adding multiple nodes at once should invalidate :first-child correctly.'); |
| |
| test(() => { |
| const target = document.querySelector('#target'); |
| const last = target.lastChild; |
| assert_equals(getComputedStyle(last).color, red); |
| target.insertAdjacentHTML('beforeend', '\n<span>foo</span><span>bar</span>'); |
| assert_equals(getComputedStyle(target.lastChild).color, red); |
| assert_equals(getComputedStyle(last).color, black); |
| while (target.lastChild !== last) |
| target.removeChild(target.lastChild); |
| assert_equals(getComputedStyle(last).color, red); |
| }, 'Adding multiple nodes at once should invalidate :last-child correctly.'); |
| |
| </script> |
| </body> |
| </html> |