| <!DOCTYPE html> |
| <title>Tests CSS transition of anchor() across three tree scopes</title> |
| <link rel="help" href="https://drafts4.csswg.org/css-anchor-position-1/"> |
| <link rel="help" href="https://github.com/w3c/csswg-drafts/issues/8180"></script> |
| <link rel="author" href="mailto:xiaochengh@chromium.org"> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| |
| <style> |
| body { |
| margin: 0; |
| } |
| |
| #anchor1 { |
| width: 100px; |
| height: 100px; |
| background: orange; |
| anchor-name: --a; |
| } |
| |
| #host.after::part(target) { |
| left: anchor(--a left); |
| } |
| </style> |
| |
| <div id="anchor1"></div> |
| <div id="host"></div> |
| |
| <script> |
| setup(() => { |
| let shadow = host.attachShadow({mode: 'open'}); |
| shadow.innerHTML = ` |
| <style> |
| div { |
| width: 100px; |
| height: 100px; |
| background: orange; |
| } |
| #anchor2 { |
| margin-left: 200px; |
| anchor-name: --a; |
| } |
| #anchor3 { |
| margin-left: 400px; |
| } |
| #target { |
| position: fixed; |
| background: lime; |
| top: 300px; |
| transition: left 10s -5s linear; |
| } |
| #target.after { |
| left: anchor(--a left); |
| } |
| </style> |
| <div id="anchor2"></div> |
| <div id="anchor3"> |
| <div id="target" part="target"></div> |
| </div> |
| `; |
| |
| let anchor3 = shadow.getElementById('anchor3'); |
| let innerShadow = anchor3.attachShadow({mode: 'open'}); |
| innerShadow.innerHTML = ` |
| <style> |
| :host { anchor-name: --a; } |
| ::slotted(*) { left: anchor(--a left); } |
| </style> |
| <slot></slot> |
| `; |
| }); |
| |
| test(() => { |
| let target = host.shadowRoot.getElementById('target'); |
| |
| // Forces layout |
| target.offsetLeft; |
| |
| // Triggers a transition from using #anchor3 to using #anchor2, |
| // starting immediately at 50% progress |
| target.classList.add('after'); |
| assert_equals(target.offsetLeft, 300); |
| |
| // Triggers another transition to using #anchor1 while the previous |
| // transition is still in progress. |
| host.classList.add('after'); |
| assert_equals(target.offsetLeft, 150); |
| }, 'Transition with anchor names defined in three different tree scopes'); |
| </script> |
