1 files changed, 45 insertions, 0 deletions
diff --git a/testing/web-platform/tests/dom/collections/HTMLCollection-delete.html b/testing/web-platform/tests/dom/collections/HTMLCollection-delete.html
new file mode 100644
index 0000000000..99420d4319
--- /dev/null
+++ b/testing/web-platform/tests/dom/collections/HTMLCollection-delete.html
@@ -0,0 +1,45 @@
+<!doctype html>
+<meta charset=utf-8>
+<title>Deleting properties from HTMLCollection</title>
+<script src=/resources/testharness.js></script>
+<script src=/resources/testharnessreport.js></script>
+<div id=log></div>
+<i id=foo></i>
+<script>
+let c, expected;
+setup(() => {
+  // These might be cached anyway, so explicitly use a single object.
+  c = document.getElementsByTagName("i");
+  expected = document.getElementById("foo");
+});
+
+test(() => {
+  assert_equals(c[0], expected, "before");
+  delete c[0];
+  assert_equals(c[0], expected, "after");
+}, "Loose id");
+
+test(() => {
+  assert_equals(c[0], expected, "before");
+  assert_throws_js(TypeError, function() {
+    "use strict";
+    delete c[0];
+  });
+  assert_equals(c[0], expected, "after");
+}, "Strict id");
+
+test(() => {
+  assert_equals(c.foo, expected, "before");
+  delete c.foo;
+  assert_equals(c.foo, expected, "after");
+}, "Loose name");
+
+test(() => {
+  assert_equals(c.foo, expected, "before");
+  assert_throws_js(TypeError, function() {
+    "use strict";
+    delete c.foo;
+  });
+  assert_equals(c.foo, expected, "after");
+}, "Strict name");
+</script>