[css-anchor-position] Fix anchors-visible on stacked children

wangxianzhu · chromium-wpt-export-bot · commit c3bc1b085f8c · 2024-04-24T08:14:50.000-07:00
Bug: 332678663 Change-Id: I7cc03c30977f07aaddf0f87462a4e9770f94deff Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5421237 Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org> Reviewed-by: Philip Rogers <pdr@chromium.org> Cr-Commit-Position: refs/heads/main@{#1282084}
diff --git a/css/css-anchor-position/position-visibility-anchors-visible-stacked-child.tentative.html b/css/css-anchor-position/position-visibility-anchors-visible-stacked-child.tentative.html
@@ -0,0 +1,60 @@
+<!DOCTYPE html>
+<meta charset="utf-8">
+<meta name="assert" content="Position-visibility: anchors-visible should hide an element and stacked children with an out-of-view anchor." />
+<title>CSS Anchor Positioning Test: position-visibility: anchors-visible</title>
+<link rel="help" href="https://github.com/w3c/csswg-drafts/issues/7758">
+<link rel="match" href="position-visibility-anchors-visible-ref.html">
+<style>
+  #scroll-container {
+    overflow: hidden scroll;
+    width: 300px;
+    height: 100px;
+  }
+
+  #anchor {
+    anchor-name: --a1;
+    width: 100px;
+    height: 100px;
+    background: orange;
+  }
+
+  #spacer {
+    height: 100px;
+  }
+
+  #target {
+    position-anchor: --a1;
+    position-visibility: anchors-visible;
+    inset-area: bottom right;
+    width: 100px;
+    height: 100px;
+    background: red;
+    position: absolute;
+    top: 0;
+    left: 0;
+  }
+  #stacking-child {
+    /* stacking context */
+    z-index: 1;
+    width: 100px;
+    height: 100px;
+    background: maroon;
+    position: absolute;
+    top: 25px;
+    left: 25px;
+  }
+</style>
+
+<div id="scroll-container">
+  <div id="anchor">anchor</div>
+  <div id="spacer"></div>
+  <div id="target">target
+    <div id="stacking-child"></div>
+  </div>
+</div>
+
+<script>
+  const scroller = document.getElementById('scroll-container');
+  scroller.scrollTop = 100;
+  // #target should not be visible because #anchor is scrolled out of view.
+</script>
