1 files changed, 64 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/semantics/embedded-content/the-img-element/picture-loading-lazy.html b/testing/web-platform/tests/html/semantics/embedded-content/the-img-element/picture-loading-lazy.html
new file mode 100644
index 0000000000..08c01616bd
--- /dev/null
+++ b/testing/web-platform/tests/html/semantics/embedded-content/the-img-element/picture-loading-lazy.html
@@ -0,0 +1,64 @@
+<!DOCTYPE html>
+<head>
+  <title>Images with loading='lazy' in picture elements load when near the viewport</title>
+  <link rel="author" title="Raj T" href="mailto:rajendrant@chromium.org">
+  <link rel="help" href="https://github.com/scott-little/lazyload">
+  <script src="/resources/testharness.js"></script>
+  <script src="/resources/testharnessreport.js"></script>
+  <script src="../resources/common.js"></script>
+</head>
+
+<script>
+const in_viewport_img = new ElementLoadPromise("in_viewport_img");
+const lazy_attribute_img = new ElementLoadPromise("lazy_attribute_img");
+const eager_attribute_img = new ElementLoadPromise("eager_attribute_img");
+
+const document_load_promise = new Promise(resolve => {
+  window.addEventListener("load", resolve);
+});
+
+async_test(function(t) {
+  document_load_promise.then(t.step_func_done(function() {
+    assert_false(lazy_attribute_img.element().complete);
+    lazy_attribute_img.element().scrollIntoView();
+  }));
+}, "Test that the loading=lazy <picture> element below viewport was deferred, on document load.");
+
+async_test(function(t) {
+  in_viewport_img.promise.then(t.step_func_done());
+}, "Test that in viewport <picture> element was loaded");
+
+async_test(function(t) {
+  eager_attribute_img.promise.then(t.step_func_done());
+}, "Test that eager <picture> element was loaded");
+
+async_test(function(t) {
+  lazy_attribute_img.promise.then(t.step_func_done());
+}, "Test that deferred <picture> element was loaded-in as well, after scrolled down");
+
+</script>
+
+<body>
+<picture>
+  <source sizes='50vw' srcset='resources/image.png?in_viewport_img'>
+  <img id='in_viewport_img' src='img-not-loaded.png' loading="lazy" onload="in_viewport_img.resolve();">
+</picture>
+<div style="height:10000px;"></div>
+<picture>
+  <source sizes='50vw' srcset='resources/image.png?lazy_attribute_img'>
+  <img id='lazy_attribute_img' src='img-not-loaded.png' loading="lazy" onload="lazy_attribute_img.resolve();">
+</picture>
+<picture>
+  <source sizes='50vw' srcset='resources/image.png?eager_attribute_img'>
+  <img id='eager_attribute_img' src='img-not-loaded.png' loading="eager" onload="eager_attribute_img.resolve();">
+</picture>
+
+<!--
+  This async script loads very slowly in order to ensure that, if the
+  below_viewport image has started loading, it has a chance to finish
+  loading before window.load() happens, so that the test will dependably fail
+  in that case instead of potentially passing depending on how long different
+  resource fetches take.
+-->
+<script async src="/common/slow.py"></script>
+</body>