[WebIDL] Test subclassing of legacy factory functions

web-platform-tests · Mar 10, 2021 · e21d42c · e21d42c
1 parent e4f56f6
commit e21d42c
Showing 1 changed file with 13 additions and 0 deletions.
diff --git a/WebIDL/ecmascript-binding/legacy-factor-function-subclass.window.js b/WebIDL/ecmascript-binding/legacy-factor-function-subclass.window.js
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+"use strict";
+
+test(() => {
+  class CustomImage extends Image {}
+  var instance = new CustomImage();
+
+  assert_equals(
+    Object.getPrototypeOf(instance), CustomImage.prototype,
+    "Object.getPrototypeOf(instance) === CustomImage.prototype");
+
+  assert_true(instance instanceof CustomImage, "instance instanceof CustomImage");
+  assert_true(instance instanceof HTMLImageElement, "instance instanceof HTMLImageElement");
+}, "[LegacyFactoryFunction] can be subclassed and correctly handles NewTarget");