Bug 1425685 - Implement HTMLSlotElement.assignedElements(); r=smaug

Differential Revision: https://phabricator.services.mozilla.com/D15653

--HG--
extra : moz-landing-system : lando

dom/html/HTMLSlotElement.cpp

@@ -141,6 +141,17 @@ void HTMLSlotElement::AssignedNodes(const AssignedNodesOptions& aOptions,
   aNodes = mAssignedNodes;
 }
 
+void HTMLSlotElement::AssignedElements(const AssignedNodesOptions& aOptions,
+                                       nsTArray<RefPtr<Element>>& aElements) {
+  AutoTArray<RefPtr<nsINode>, 128> assignedNodes;
+  AssignedNodes(aOptions, assignedNodes);
+  for (const RefPtr<nsINode>& assignedNode : assignedNodes) {
+    if (assignedNode->IsElement()) {
+      aElements.AppendElement(assignedNode->AsElement());
+    }
+  }
+}
+
 const nsTArray<RefPtr<nsINode>>& HTMLSlotElement::AssignedNodes() const {
   return mAssignedNodes;
 }

dom/html/HTMLSlotElement.h

@@ -50,6 +50,9 @@ class HTMLSlotElement final : public nsGenericHTMLElement {
   void AssignedNodes(const AssignedNodesOptions& aOptions,
                      nsTArray<RefPtr<nsINode>>& aNodes);
 
+  void AssignedElements(const AssignedNodesOptions& aOptions,
+                        nsTArray<RefPtr<Element>>& aNodes);
+
   // Helper methods
   const nsTArray<RefPtr<nsINode>>& AssignedNodes() const;
   void InsertAssignedNode(uint32_t aIndex, nsINode* aNode);

dom/webidl/HTMLSlotElement.webidl

@@ -15,6 +15,7 @@
 interface HTMLSlotElement : HTMLElement {
   [CEReactions, SetterThrows] attribute DOMString name;
   sequence<Node> assignedNodes(optional AssignedNodesOptions options);
+  sequence<Element> assignedElements(optional AssignedNodesOptions options);
 };
 
 dictionary AssignedNodesOptions {

testing/web-platform/meta/html/dom/interfaces.https.html.ini

@@ -631,15 +631,6 @@
   [HTMLDialogElement interface: operation close(DOMString)]
     expected: FAIL
 
-  [HTMLSlotElement interface: operation assignedElements(AssignedNodesOptions)]
-    expected: FAIL
-
-  [HTMLSlotElement interface: document.createElement("slot") must inherit property "assignedElements(AssignedNodesOptions)" with the proper type]
-    expected: FAIL
-
-  [HTMLSlotElement interface: calling assignedElements(AssignedNodesOptions) on document.createElement("slot") with too few arguments must throw TypeError]
-    expected: FAIL
-
   [HTMLCanvasElement interface: operation transferControlToOffscreen()]
     expected: FAIL
 

testing/web-platform/meta/shadow-dom/slots-fallback.html.ini

@@ -1,10 +0,0 @@
-[slots-fallback.html]
-  [Slots fallback: Basic, elements only.]
-    expected: FAIL
-
-  [Slots fallback: Slots in Slots, elements only.]
-    expected: FAIL
-
-  [Slots fallback: Complex case, elements only.]
-    expected: FAIL
-

testing/web-platform/meta/shadow-dom/slots.html.ini

@@ -1,10 +0,0 @@
-[slots.html]
-  [Slots: Basic, elements only.]
-    expected: FAIL
-
-  [Slots: Slots in closed, elements only.]
-    expected: FAIL
-
-  [Slots: Slots not in a shadow tree, elements only.]
-    expected: FAIL
-