1 files changed, 52 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/semantics/embedded-content/the-iframe-element/iframe-loading-eager.html b/testing/web-platform/tests/html/semantics/embedded-content/the-iframe-element/iframe-loading-eager.html
new file mode 100644
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+++ b/testing/web-platform/tests/html/semantics/embedded-content/the-iframe-element/iframe-loading-eager.html
@@ -0,0 +1,52 @@
+<!DOCTYPE html>
+<head>
+  <title>Iframes with loading='eager' load immediately regardless of their
+         position with respect to the viewport.</title>
+  <link rel="author" title="Scott Little" href="mailto:sclittle@chromium.org">
+  <link rel="help" href="https://github.com/scott-little/lazyload">
+  <script src="/resources/testharness.js"></script>
+  <script src="/resources/testharnessreport.js"></script>
+</head>
+
+<script>
+  const t = async_test("Test that iframes with loading='eager' load " +
+                       "immediately regardless of their position with " +
+                       "respect to the viewport.");
+
+  let has_in_viewport_loaded = false;
+  const in_viewport_iframe_onload = t.step_func(() => {
+    assert_false(has_in_viewport_loaded,
+                 "The in_viewport element should load only once.");
+    has_in_viewport_loaded = true;
+  });
+
+  let has_below_viewport_loaded = false;
+  const below_viewport_iframe_onload = t.step_func(() => {
+    assert_false(has_below_viewport_loaded,
+                 "The below_viewport element should load only once.");
+    has_below_viewport_loaded = true;
+  });
+
+  window.addEventListener("load", t.step_func_done(() => {
+    assert_true(has_in_viewport_loaded,
+                "The in_viewport element should have loaded before " +
+                "window.load().");
+    assert_true(has_below_viewport_loaded,
+                "The below_viewport element should have loaded before " +
+                "window.load().");
+  }));
+</script>
+
+<body>
+  <iframe id="in_viewport" src="resources/subframe.html?in-viewport"
+          loading="eager" width="200px" height="100px"
+          onload="in_viewport_iframe_onload();"></iframe>
+  <div style="height:1000vh;"></div>
+
+  <!-- The below_viewport element loads very slowly in order to ensure that the
+       window load event is blocked on it. -->
+  <iframe id="below_viewport"
+          src="resources/subframe.html?below-viewport&pipe=trickle(d1)"
+          loading="eager" width="200px" height="100px"
+          onload="below_viewport_iframe_onload();"></iframe>
+</body>