Fix form.elements to use form owner instead of only descendants

ccwebdesign · web-flow · commit af7e1d9120ce · 2020-07-11T14:03:03.000-04:00
Closes #2628.
diff --git a/lib/jsdom/living/nodes/HTMLFormElement-impl.js b/lib/jsdom/living/nodes/HTMLFormElement-impl.js
@@ -5,7 +5,7 @@ const { serializeURL } = require("whatwg-url");
 const HTMLElementImpl = require("./HTMLElement-impl").implementation;
 const { domSymbolTree } = require("../helpers/internal-constants");
 const { fireAnEvent } = require("../helpers/events");
-const { isListed, isSubmittable, isSubmitButton } = require("../helpers/form-controls");
+const { formOwner, isListed, isSubmittable, isSubmitButton } = require("../helpers/form-controls");
 const HTMLCollection = require("../generated/HTMLCollection");
 const notImplemented = require("../../browser/not-implemented");
 const { parseURLToResultingURLRecord } = require("../helpers/document-base-url");
@@ -47,14 +47,24 @@ class HTMLFormElementImpl extends HTMLElementImpl {
     super._descendantRemoved.apply(this, arguments);
   }
 
+  _getElementNodes() {
+    return domSymbolTree.treeToArray(this.getRootNode({}), {
+      filter: node => {
+        if (!isListed(node) || (node._localName === "input" && node.type === "image")) {
+          return false;
+        }
+
+        return formOwner(node) === this;
+      }
+    });
+  }
+
   // https://html.spec.whatwg.org/multipage/forms.html#dom-form-elements
   get elements() {
     // TODO: Return a HTMLFormControlsCollection
     return HTMLCollection.createImpl(this._globalObject, [], {
-      element: this,
-      query: () => domSymbolTree.treeToArray(this, {
-        filter: node => isListed(node) && (node._localName !== "input" || node.type !== "image")
-      })
+      element: this.getRootNode({}),
+      query: () => this._getElementNodes()
     });
   }
 
diff --git a/test/web-platform-tests/to-run.yaml b/test/web-platform-tests/to-run.yaml
@@ -707,7 +707,6 @@ DIR: html/semantics/forms/the-form-element
 form-action-submission-with-base-url.html: [timeout, Unknown]
 form-action-submission.html: [timeout, Unknown]
 form-autocomplete.html: [fail, Unknown]
-form-elements-filter.html: [fail, Unknown]
 form-elements-interfaces-01.html: [fail, Unknown]
 form-elements-nameditem-01.html: [fail, Unknown]
 form-indexed-element.html: [fail, Unknown]
diff --git a/test/web-platform-tests/to-upstream/html/semantics/forms/the-form-element/form-elements-form-owner.html b/test/web-platform-tests/to-upstream/html/semantics/forms/the-form-element/form-elements-form-owner.html
@@ -0,0 +1,32 @@
+<!DOCTYPE html>
+<meta charset="utf-8" />
+<title>Form.elements should update on form.id change</title>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<div id=log></div>
+
+<form name="test">
+  <input name="internal" form="testForm" type="hidden" />
+</form>
+<input name="external" form="testForm" type="hidden" />
+
+<script>
+"use strict";
+
+test(() => {
+  const form = document.querySelector("form");
+
+  assert_equals(form.elements.length, 0);
+}, "`form.elements` should not contain elements inside form with different form owner");
+
+test(() => {
+  const form = document.querySelector("form");
+
+  assert_equals(form.elements.length, 0, "pre-condition");
+
+  form.id = "testForm";
+
+  assert_equals(form.elements.length, 2);
+}, "`form.elements` should update on form.id change");
+
+</script>
