Bug 1912520 - Morph aria-owns to controls relationship when container is combobox. r=Jamie

Differential Revision: https://phabricator.services.mozilla.com/D236931

accessible/base/nsAccUtils.cpp

@@ -637,3 +637,13 @@ int32_t nsAccUtils::FindARIAAttrValueIn(dom::Element* aElement,
   }
   return index;
 }
+
+bool nsAccUtils::IsEditableARIACombobox(const LocalAccessible* aAccessible) {
+  const nsRoleMapEntry* roleMap = aAccessible->ARIARoleMap();
+  if (!roleMap || roleMap->role != roles::EDITCOMBOBOX) {
+    return false;
+  }
+
+  return aAccessible->IsTextField() ||
+         aAccessible->Elm()->State().HasState(dom::ElementState::READWRITE);
+}

accessible/base/nsAccUtils.h

@@ -301,6 +301,8 @@ class nsAccUtils {
                                      const nsAtom* aName,
                                      AttrArray::AttrValuesArray* aValues,
                                      nsCaseTreatment aCaseSensitive);
+
+  static bool IsEditableARIACombobox(const LocalAccessible* aAccessible);
 };
 
 }  // namespace a11y

accessible/generic/DocAccessible.cpp

@@ -2470,6 +2470,13 @@ void DocAccessible::DoARIAOwnsRelocation(LocalAccessible* aOwner) {
   logging::TreeInfo("aria owns relocation", logging::eVerbose, aOwner);
 #endif
 
+  const nsRoleMapEntry* roleMap = aOwner->ARIARoleMap();
+  if (roleMap && roleMap->role == roles::EDITCOMBOBOX) {
+    // The READWRITE state of a combobox may sever aria-owns relations
+    // we fallback to "controls" relations.
+    QueueCacheUpdate(aOwner, CacheDomain::Relations);
+  }
+
   nsTArray<RefPtr<LocalAccessible>>* owned =
       mARIAOwnsHash.GetOrInsertNew(aOwner);
 

accessible/generic/LocalAccessible.cpp

@@ -2281,14 +2281,32 @@ Relation LocalAccessible::RelationByType(RelationType aType) const {
       return Relation();
     }
 
-    case RelationType::CONTROLLED_BY:
-      return Relation(new RelatedAccIterator(Document(), mContent,
-                                             nsGkAtoms::aria_controls));
+    case RelationType::CONTROLLED_BY: {
+      Relation rel(new RelatedAccIterator(Document(), mContent,
+                                          nsGkAtoms::aria_controls));
 
+      RelatedAccIterator owners(Document(), mContent, nsGkAtoms::aria_owns);
+      if (LocalAccessible* owner = owners.Next()) {
+        if (nsAccUtils::IsEditableARIACombobox(owner)) {
+          MOZ_ASSERT(!IsRelocated(),
+                     "Child is not relocated to editable combobox");
+          rel.AppendTarget(owner);
+        }
+      }
+
+      return rel;
+    }
     case RelationType::CONTROLLER_FOR: {
       Relation rel(new AssociatedElementsIterator(mDoc, mContent,
                                                   nsGkAtoms::aria_controls));
       rel.AppendIter(new HTMLOutputIterator(Document(), mContent));
+      if (nsAccUtils::IsEditableARIACombobox(this)) {
+        AssociatedElementsIterator iter(mDoc, mContent, nsGkAtoms::aria_owns);
+        while (Accessible* owned_child = iter.Next()) {
+          MOZ_ASSERT(!owned_child->AsLocal()->IsRelocated());
+          rel.AppendTarget(owned_child->AsLocal());
+        }
+      }
       return rel;
     }
 
@@ -4080,11 +4098,17 @@ already_AddRefed<AccAttributes> LocalAccessible::BundleFieldsForCache(
                 dom::HTMLLabelElement::FromNode(mContent)) {
           rel.AppendTarget(mDoc, labelEl->GetControl());
         }
-      } else if (data.mType == RelationType::DETAILS) {
+      } else if (data.mType == RelationType::DETAILS ||
+                 data.mType == RelationType::CONTROLLER_FOR) {
         // We need to use RelationByType for details because it might include
         // popovertarget. Nothing exposes an implicit reverse details
         // relation, so using RelationByType here is fine.
-        rel = RelationByType(RelationType::DETAILS);
+        //
+        // We need to use RelationByType for controls because it might include
+        // failed aria-owned relocations or it may be an output element.
+        // Nothing exposes an implicit reverse controls relation, so using
+        // RelationByType here is fine.
+        rel = RelationByType(data.mType);
       } else {
         // We use an AssociatedElementsIterator here instead of calling
         // RelationByType directly because we only want to cache explicit

accessible/tests/browser/e10s/browser_treeupdate_ariaowns.js

@@ -622,8 +622,8 @@ addAccessibleTask(
   async function (browser, accDoc) {
     const p = findAccessibleChildByID(accDoc, "p");
     const textbox = findAccessibleChildByID(accDoc, "textbox");
-    testStates(textbox, 0, EXT_STATE_EDITABLE, 0, 0);
 
+    testStates(textbox, 0, EXT_STATE_EDITABLE, 0, 0);
     isnot(getAccessibleDOMNodeID(p.lastChild), "btn", "'p' owns relocated btn");
     is(textbox.value, "Hello");
 
@@ -700,3 +700,39 @@ addAccessibleTask(
     );
   }
 );
+
+addAccessibleTask(
+  `
+  <div id="box" role="combobox"
+         aria-owns="listbox"
+         aria-expanded="true"
+         aria-haspopup="listbox"
+         aria-autocomplete="list"
+         contenteditable="true"></div>
+  <ul role="listbox" id="listbox">
+    <li role="option">apple</li>
+    <li role="option">peach</li>
+  </ul>
+`,
+  async (browser, accDoc) => {
+    const combobox = findAccessibleChildByID(accDoc, "box");
+    const listbox = findAccessibleChildByID(accDoc, "listbox");
+
+    testStates(combobox, 0, EXT_STATE_EDITABLE, 0, 0);
+    is(combobox.childCount, 0, "combobox has no children");
+    await testCachedRelation(combobox, RELATION_CONTROLLER_FOR, [listbox]);
+    await testCachedRelation(listbox, RELATION_CONTROLLED_BY, [combobox]);
+
+    let expectedEvents = Promise.all([
+      waitForStateChange(combobox, EXT_STATE_EDITABLE, false, true),
+      waitForEvent(EVENT_REORDER, accDoc),
+    ]);
+    await invokeContentTask(browser, [], () => {
+      content.document.getElementById("box").contentEditable = false;
+    });
+    await expectedEvents;
+    await testCachedRelation(combobox, RELATION_CONTROLLER_FOR, []);
+    await testCachedRelation(listbox, RELATION_CONTROLLED_BY, []);
+    is(combobox.childCount, 1, "combobox has listbox");
+  }
+);