1 files changed, 94 insertions, 0 deletions
diff --git a/testing/web-platform/tests/css/css-view-transitions/pseudo-get-computed-style.html b/testing/web-platform/tests/css/css-view-transitions/pseudo-get-computed-style.html
new file mode 100644
index 0000000000..45d2559b3e
--- /dev/null
+++ b/testing/web-platform/tests/css/css-view-transitions/pseudo-get-computed-style.html
@@ -0,0 +1,94 @@
+<!DOCTYPE html>
+<html>
+<title>Shared transitions: check pseudo element's display property</title>
+<link rel="help" href="https://github.com/WICG/view-transitions">
+<link rel="author" href="mailto:vmpstr@chromium.org">
+
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+
+<style>
+div {
+  width: 100px;
+  height: 100px;
+  background: blue;
+  contain: paint;
+  view-transition-name: target;
+}
+::view-transition-image-pair(target) {
+  position: fixed;
+}
+</style>
+
+<div id=target></div>
+
+<script>
+promise_test(() => {
+  assert_implements(document.startViewTransition, "Missing document.startViewTransition");
+  return new Promise(async (resolve, reject) => {
+    let transition = document.startViewTransition(() => {
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition").position, "fixed", ":view-transition");
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(target)").position, "absolute", "container(target)");
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-image-pair(target)").position, "absolute", "wrapper(target)");
+
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-old(target)").position, "absolute", "outgoing(target)");
+
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(root)").position, "absolute", "container(root)");
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-image-pair(root)").position, "absolute", "wrapper(root)");
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-old(root)").position, "absolute", "outgoing(root)");
+
+      requestAnimationFrame(() => {
+        assert_equals(getComputedStyle(document.documentElement, ":view-transition").position, "fixed", "raf :view-transition");
+        assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(target)").position, "absolute", "raf container(target)");
+        assert_equals(getComputedStyle(document.documentElement, ":view-transition-image-pair(target)").position, "fixed", "raf wrapper(target)");
+
+        assert_equals(getComputedStyle(document.documentElement, ":view-transition-old(target)").position, "absolute", "raf outgoing(target)");
+
+        assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(root)").position, "absolute", "raf container(root)");
+        assert_equals(getComputedStyle(document.documentElement, ":view-transition-image-pair(root)").position, "absolute", "raf wrapper(root)");
+        assert_equals(getComputedStyle(document.documentElement, ":view-transition-old(root)").position, "absolute", "raf outgoing(root)");
+      });
+    });
+    await transition.finished;
+    resolve();
+  });
+}, "position property of pseudo elements");
+
+promise_test(() => {
+  assert_implements(document.startViewTransition, "Missing document.startViewTransition");
+  return new Promise(async (resolve, reject) => {
+    let transition = document.startViewTransition(() => {
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition").position, "fixed");
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(target)").position, "absolute");
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-image-pair(target)").position, "absolute");
+
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-old(target)").position, "absolute");
+
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(root)").position, "absolute");
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-image-pair(root)").position, "absolute");
+      assert_equals(getComputedStyle(document.documentElement, ":view-transition-old(root)").position, "absolute");
+    });
+
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition").position, "fixed");
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(target)").position, "absolute");
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-image-pair(target)").position, "fixed");
+
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-old(target)").position, "absolute");
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-new(target)").position, "absolute");
+
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(root)").position, "absolute");
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-image-pair(root)").position, "absolute");
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-old(root)").position, "absolute");
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-new(root)").position, "absolute");
+
+    assert_equals(getComputedStyle(document.documentElement, ":view-transition-group(target)").position, "absolute");
+
+    await transition.finished;
+
+    // With custom ua sheets not applying to non-existing pseudo, the value should be the default (not absolute)
+    assert_not_equals(getComputedStyle(document.documentElement, ":view-transition-group(target)").position, "absolute");
+
+    resolve();
+  });
+}, "position property of pseudo elements with prepare api");
+</script>