Relation list properties for Accessibility Object Model phase 1

third_party/WebKit/Source/modules/accessibility/AXObject.cpp

Index: third_party/WebKit/Source/modules/accessibility/AXObject.cpp
diff --git a/third_party/WebKit/Source/modules/accessibility/AXObject.cpp b/third_party/WebKit/Source/modules/accessibility/AXObject.cpp
index f7145d1222ce32544ce1452749a5150af2eccd15..9b57268a1c7413016d765461dcacf817af08ca56 100644
--- a/third_party/WebKit/Source/modules/accessibility/AXObject.cpp
+++ b/third_party/WebKit/Source/modules/accessibility/AXObject.cpp
@@ -392,6 +392,25 @@ Element* AXObject::GetAOMPropertyOrARIAAttribute(
   return target ? target->element() : nullptr;
 }
 
+bool AXObject::HasAOMProperty(AOMRelationListProperty property,
+                              HeapVector<Member<Element>>& result) const {
+  Element* element = this->GetElement();
+  if (!element)
+    return false;
+
+  return AccessibleNode::GetProperty(element, property, result);
+}
+
+bool AXObject::HasAOMPropertyOrARIAAttribute(
+    AOMRelationListProperty property,
+    HeapVector<Member<Element>>& result) const {
+  Element* element = this->GetElement();
+  if (!element)
+    return false;
+
+  return AccessibleNode::GetPropertyOrARIAAttribute(element, property, result);
+}
+
 bool AXObject::HasAOMPropertyOrARIAAttribute(AOMBooleanProperty property,
                                              bool& result) const {
   Element* element = this->GetElement();
@@ -975,6 +994,43 @@ String AXObject::AriaTextAlternative(bool recursive,
   }
 
   // Step 2B from: http://www.w3.org/TR/accname-aam-1.1
+  // AOM version
+  // If you change this logic, update AXNodeObject::nameFromLabelElement, too.
+  if (!in_aria_labelled_by_traversal && !already_visited) {
+    name_from = kAXNameFromRelatedElement;
+    if (name_sources) {
+      name_sources->push_back(
+          NameSource(*found_text_alternative, aria_labeledbyAttr));

[aboxhall, 2017/07/06 05:37:14]

Hm, I think we should have a different source for AOM properties (and should
there be an AOM version for aria_label as well?)

[dmazzoni, 2017/07/06 06:34:25]

For aria-label and almost every other place in the code where we were
previously getting an ARIA attribute, we're now calling
GetAOMPropertyOrARIAAttribute,
which allows us to not duplicate all of that code.

I'd be totally open to being more explicit about the AOM in developer tools,
but I think it's beyond the scope of this change since we haven't been doing
it for other properties yet.

Considering AOM in general is still experimental and subject to change, we
may also want to consider holding off on adding "extra" dev tools support,
and defer that until we're closer to wanting to ship this.

[aboxhall, 2017/07/06 06:55:15]

Makes sense!

+      name_sources->back().type = name_from;
+    }
+
+    HeapVector<Member<Element>> elements;
+    if (HasAOMProperty(AOMRelationListProperty::kLabeledBy, elements)) {
+      // Operate on a copy of |visited| so that if |nameSources| is not null,
+      // the set of visited objects is preserved unmodified for future
+      // calculations.
+      AXObjectSet visited_copy = visited;
+      text_alternative =
+          TextFromElements(true, visited_copy, elements, related_objects);
+      if (!text_alternative.IsNull()) {
+        if (name_sources) {
+          NameSource& source = name_sources->back();
+          source.type = name_from;
+          source.related_objects = *related_objects;
+          source.text = text_alternative;
+          *found_text_alternative = true;
+        } else {
+          *found_text_alternative = true;
+          return text_alternative;
+        }
+      } else if (name_sources) {
+        name_sources->back().invalid = true;
+      }
+    }
+  }
+
+  // Step 2B from: http://www.w3.org/TR/accname-aam-1.1
+  // ARIA version
   // If you change this logic, update AXNodeObject::nameFromLabelElement, too.
   if (!in_aria_labelled_by_traversal && !already_visited) {
     const QualifiedName& attr =