1 files changed, 1003 insertions, 0 deletions
diff --git a/accessible/mac/mozAccessible.mm b/accessible/mac/mozAccessible.mm
new file mode 100644
index 0000000000..2d8e140343
--- /dev/null
+++ b/accessible/mac/mozAccessible.mm
@@ -0,0 +1,1003 @@
+/* clang-format off */
+/* -*- Mode: Objective-C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* clang-format on */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#import "mozAccessible.h"
+#include "MOXAccessibleBase.h"
+
+#import "MacUtils.h"
+#import "mozView.h"
+#import "MOXSearchInfo.h"
+#import "MOXTextMarkerDelegate.h"
+#import "MOXWebAreaAccessible.h"
+#import "mozTextAccessible.h"
+#import "mozRootAccessible.h"
+
+#include "LocalAccessible-inl.h"
+#include "nsAccUtils.h"
+#include "DocAccessibleParent.h"
+#include "Relation.h"
+#include "mozilla/a11y/Role.h"
+#include "RootAccessible.h"
+#include "mozilla/a11y/PDocAccessible.h"
+#include "mozilla/dom/BrowserParent.h"
+#include "OuterDocAccessible.h"
+#include "nsChildView.h"
+#include "xpcAccessibleMacInterface.h"
+
+#include "nsRect.h"
+#include "nsCocoaUtils.h"
+#include "nsCoord.h"
+#include "nsObjCExceptions.h"
+#include "nsWhitespaceTokenizer.h"
+#include <prdtoa.h>
+
+using namespace mozilla;
+using namespace mozilla::a11y;
+
+#pragma mark -
+
+@interface mozAccessible ()
+- (BOOL)providesLabelNotTitle;
+
+- (void)maybePostLiveRegionChanged;
+- (void)maybePostA11yUtilNotification;
+@end
+
+@implementation mozAccessible
+
+- (id)initWithAccessible:(Accessible*)aAcc {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+  MOZ_ASSERT(aAcc, "Cannot init mozAccessible with null");
+  if ((self = [super init])) {
+    mGeckoAccessible = aAcc;
+    mRole = aAcc->Role();
+  }
+
+  return self;
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(nil);
+}
+
+- (void)dealloc {
+  NS_OBJC_BEGIN_TRY_IGNORE_BLOCK;
+
+  [super dealloc];
+
+  NS_OBJC_END_TRY_IGNORE_BLOCK;
+}
+
+#pragma mark - mozAccessible widget
+
+- (BOOL)hasRepresentedView {
+  return NO;
+}
+
+- (id)representedView {
+  return nil;
+}
+
+- (BOOL)isRoot {
+  return NO;
+}
+
+#pragma mark -
+
+- (BOOL)moxIgnoreWithParent:(mozAccessible*)parent {
+  if (LocalAccessible* acc = mGeckoAccessible->AsLocal()) {
+    if (acc->IsContent() && acc->GetContent()->IsXULElement()) {
+      if (acc->VisibilityState() & states::INVISIBLE) {
+        return YES;
+      }
+    }
+  }
+
+  return [parent moxIgnoreChild:self];
+}
+
+- (BOOL)moxIgnoreChild:(mozAccessible*)child {
+  return nsAccUtils::MustPrune(mGeckoAccessible);
+}
+
+- (id)childAt:(uint32_t)i {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+
+  Accessible* child = mGeckoAccessible->ChildAt(i);
+  return child ? GetNativeFromGeckoAccessible(child) : nil;
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(nil);
+}
+
+- (uint64_t)state {
+  return mGeckoAccessible->State();
+}
+
+- (uint64_t)stateWithMask:(uint64_t)mask {
+  return [self state] & mask;
+}
+
+- (void)stateChanged:(uint64_t)state isEnabled:(BOOL)enabled {
+  if (state == states::BUSY) {
+    [self moxPostNotification:@"AXElementBusyChanged"];
+  }
+}
+
+- (BOOL)providesLabelNotTitle {
+  // These accessible types are the exception to the rule of label vs. title:
+  // They may be named explicitly, but they still provide a label not a title.
+  return mRole == roles::GROUPING || mRole == roles::RADIO_GROUP ||
+         mRole == roles::FIGURE || mRole == roles::GRAPHIC ||
+         mRole == roles::DOCUMENT || mRole == roles::OUTLINE ||
+         mRole == roles::ARTICLE || mRole == roles::ENTRY ||
+         mRole == roles::SPINBUTTON;
+}
+
+- (mozilla::a11y::Accessible*)geckoAccessible {
+  return mGeckoAccessible;
+}
+
+#pragma mark - MOXAccessible protocol
+
+- (BOOL)moxBlockSelector:(SEL)selector {
+  if (selector == @selector(moxPerformPress)) {
+    uint8_t actionCount = mGeckoAccessible->ActionCount();
+
+    // If we have no action, we don't support press, so return YES.
+    return actionCount == 0;
+  }
+
+  if (selector == @selector(moxSetFocused:)) {
+    return [self stateWithMask:states::FOCUSABLE] == 0;
+  }
+
+  if (selector == @selector(moxARIALive) ||
+      selector == @selector(moxARIAAtomic) ||
+      selector == @selector(moxARIARelevant)) {
+    return ![self moxIsLiveRegion];
+  }
+
+  if (selector == @selector(moxARIAPosInSet) || selector == @selector
+                                                    (moxARIASetSize)) {
+    GroupPos groupPos = mGeckoAccessible->GroupPosition();
+    return groupPos.setSize == 0;
+  }
+
+  if (selector == @selector(moxExpanded)) {
+    return [self stateWithMask:states::EXPANDABLE] == 0;
+  }
+
+  return [super moxBlockSelector:selector];
+}
+
+- (id)moxFocusedUIElement {
+  MOZ_ASSERT(mGeckoAccessible);
+  // This only gets queried on the web area or the root group
+  // so just use the doc's focused child instead of trying to get
+  // the focused child of mGeckoAccessible.
+  Accessible* doc = nsAccUtils::DocumentFor(mGeckoAccessible);
+  mozAccessible* focusedChild =
+      GetNativeFromGeckoAccessible(doc->FocusedChild());
+
+  if ([focusedChild isAccessibilityElement]) {
+    return focusedChild;
+  }
+
+  // return ourself if we can't get a native focused child.
+  return self;
+}
+
+- (id<MOXTextMarkerSupport>)moxTextMarkerDelegate {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  return [MOXTextMarkerDelegate
+      getOrCreateForDoc:nsAccUtils::DocumentFor(mGeckoAccessible)];
+}
+
+- (BOOL)moxIsLiveRegion {
+  return mIsLiveRegion;
+}
+
+- (id)moxHitTest:(NSPoint)point {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  // Convert the given screen-global point in the cocoa coordinate system (with
+  // origin in the bottom-left corner of the screen) into point in the Gecko
+  // coordinate system (with origin in a top-left screen point).
+  NSScreen* mainView = [[NSScreen screens] objectAtIndex:0];
+  NSPoint tmpPoint =
+      NSMakePoint(point.x, [mainView frame].size.height - point.y);
+  LayoutDeviceIntPoint geckoPoint = nsCocoaUtils::CocoaPointsToDevPixels(
+      tmpPoint, nsCocoaUtils::GetBackingScaleFactor(mainView));
+
+  Accessible* child = mGeckoAccessible->ChildAtPoint(
+      geckoPoint.x, geckoPoint.y, Accessible::EWhichChildAtPoint::DeepestChild);
+
+  if (child) {
+    mozAccessible* nativeChild = GetNativeFromGeckoAccessible(child);
+    return [nativeChild isAccessibilityElement]
+               ? nativeChild
+               : [nativeChild moxUnignoredParent];
+  }
+
+  // if we didn't find anything, return ourself or child view.
+  return self;
+}
+
+- (id<mozAccessible>)moxParent {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+  if ([self isExpired]) {
+    return nil;
+  }
+
+  Accessible* parent = mGeckoAccessible->Parent();
+
+  if (!parent) {
+    return nil;
+  }
+
+  id nativeParent = GetNativeFromGeckoAccessible(parent);
+  if ([nativeParent isKindOfClass:[MOXWebAreaAccessible class]]) {
+    // Before returning a WebArea as parent, check to see if
+    // there is a generated root group that is an intermediate container.
+    if (id<mozAccessible> rootGroup = [nativeParent rootGroup]) {
+      nativeParent = rootGroup;
+    }
+  }
+
+  if (!nativeParent && mGeckoAccessible->IsLocal()) {
+    // Return native of root accessible if we have no direct parent.
+    // XXX: need to return a sensible fallback in proxy case as well
+    nativeParent = GetNativeFromGeckoAccessible(
+        mGeckoAccessible->AsLocal()->RootAccessible());
+  }
+
+  return GetObjectOrRepresentedView(nativeParent);
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(nil);
+}
+
+// gets all our native children lazily, including those that are ignored.
+- (NSArray*)moxChildren {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  NSMutableArray* children = [[[NSMutableArray alloc]
+      initWithCapacity:mGeckoAccessible->ChildCount()] autorelease];
+
+  for (uint32_t childIdx = 0; childIdx < mGeckoAccessible->ChildCount();
+       childIdx++) {
+    Accessible* child = mGeckoAccessible->ChildAt(childIdx);
+    mozAccessible* nativeChild = GetNativeFromGeckoAccessible(child);
+    if (!nativeChild) {
+      continue;
+    }
+
+    [children addObject:nativeChild];
+  }
+
+  return children;
+}
+
+- (NSValue*)moxPosition {
+  CGRect frame = [[self moxFrame] rectValue];
+
+  return [NSValue valueWithPoint:NSMakePoint(frame.origin.x, frame.origin.y)];
+}
+
+- (NSValue*)moxSize {
+  CGRect frame = [[self moxFrame] rectValue];
+
+  return
+      [NSValue valueWithSize:NSMakeSize(frame.size.width, frame.size.height)];
+}
+
+- (NSString*)moxRole {
+#define ROLE(geckoRole, stringRole, ariaRole, atkRole, macRole, macSubrole, \
+             msaaRole, ia2Role, androidClass, nameRule)                     \
+  case roles::geckoRole:                                                    \
+    return macRole;
+
+  switch (mRole) {
+#include "RoleMap.h"
+    default:
+      MOZ_ASSERT_UNREACHABLE("Unknown role.");
+      return NSAccessibilityUnknownRole;
+  }
+
+#undef ROLE
+}
+
+- (nsStaticAtom*)ARIARole {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  if (mGeckoAccessible->HasARIARole()) {
+    const nsRoleMapEntry* roleMap = mGeckoAccessible->ARIARoleMap();
+    return roleMap->roleAtom;
+  }
+
+  return nsGkAtoms::_empty;
+}
+
+- (NSString*)moxSubrole {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  // Deal with landmarks first
+  // macOS groups the specific landmark types of DPub ARIA into two broad
+  // categories with corresponding subroles: Navigation and region/container.
+  if (mRole == roles::LANDMARK) {
+    nsAtom* landmark = mGeckoAccessible->LandmarkRole();
+    // HTML Elements treated as landmarks, and ARIA landmarks.
+    if (landmark) {
+      if (landmark == nsGkAtoms::banner) return @"AXLandmarkBanner";
+      if (landmark == nsGkAtoms::complementary)
+        return @"AXLandmarkComplementary";
+      if (landmark == nsGkAtoms::contentinfo) return @"AXLandmarkContentInfo";
+      if (landmark == nsGkAtoms::main) return @"AXLandmarkMain";
+      if (landmark == nsGkAtoms::navigation) return @"AXLandmarkNavigation";
+      if (landmark == nsGkAtoms::search) return @"AXLandmarkSearch";
+    }
+
+    // None of the above, so assume DPub ARIA.
+    return @"AXLandmarkRegion";
+  }
+
+  // Now, deal with widget roles
+  nsStaticAtom* roleAtom = nullptr;
+
+  if (mRole == roles::DIALOG) {
+    roleAtom = [self ARIARole];
+
+    if (roleAtom == nsGkAtoms::alertdialog) {
+      return @"AXApplicationAlertDialog";
+    }
+    if (roleAtom == nsGkAtoms::dialog) {
+      return @"AXApplicationDialog";
+    }
+  }
+
+  if (mRole == roles::FORM) {
+    roleAtom = [self ARIARole];
+
+    if (roleAtom == nsGkAtoms::form) {
+      return @"AXLandmarkForm";
+    }
+  }
+
+#define ROLE(geckoRole, stringRole, ariaRole, atkRole, macRole, macSubrole, \
+             msaaRole, ia2Role, androidClass, nameRule)                     \
+  case roles::geckoRole:                                                    \
+    if (![macSubrole isEqualToString:NSAccessibilityUnknownSubrole]) {      \
+      return macSubrole;                                                    \
+    } else {                                                                \
+      break;                                                                \
+    }
+
+  switch (mRole) {
+#include "RoleMap.h"
+  }
+
+  // These are special. They map to roles::NOTHING
+  // and are instructed by the ARIA map to use the native host role.
+  roleAtom = [self ARIARole];
+
+  if (roleAtom == nsGkAtoms::log_) {
+    return @"AXApplicationLog";
+  }
+
+  if (roleAtom == nsGkAtoms::timer) {
+    return @"AXApplicationTimer";
+  }
+  // macOS added an AXSubrole value to distinguish generic AXGroup objects
+  // from those which are AXGroups as a result of an explicit ARIA role,
+  // such as the non-landmark, non-listitem text containers in DPub ARIA.
+  if (mRole == roles::FOOTNOTE || mRole == roles::SECTION) {
+    return @"AXApplicationGroup";
+  }
+
+  return NSAccessibilityUnknownSubrole;
+
+#undef ROLE
+}
+
+struct RoleDescrMap {
+  NSString* role;
+  const nsString description;
+};
+
+static const RoleDescrMap sRoleDescrMap[] = {
+    {@"AXApplicationAlert", u"alert"_ns},
+    {@"AXApplicationAlertDialog", u"alertDialog"_ns},
+    {@"AXApplicationDialog", u"dialog"_ns},
+    {@"AXApplicationLog", u"log"_ns},
+    {@"AXApplicationMarquee", u"marquee"_ns},
+    {@"AXApplicationStatus", u"status"_ns},
+    {@"AXApplicationTimer", u"timer"_ns},
+    {@"AXContentSeparator", u"separator"_ns},
+    {@"AXDefinition", u"definition"_ns},
+    {@"AXDetails", u"details"_ns},
+    {@"AXDocument", u"document"_ns},
+    {@"AXDocumentArticle", u"article"_ns},
+    {@"AXDocumentMath", u"math"_ns},
+    {@"AXDocumentNote", u"note"_ns},
+    {@"AXLandmarkApplication", u"application"_ns},
+    {@"AXLandmarkBanner", u"banner"_ns},
+    {@"AXLandmarkComplementary", u"complementary"_ns},
+    {@"AXLandmarkContentInfo", u"content"_ns},
+    {@"AXLandmarkMain", u"main"_ns},
+    {@"AXLandmarkNavigation", u"navigation"_ns},
+    {@"AXLandmarkRegion", u"region"_ns},
+    {@"AXLandmarkSearch", u"search"_ns},
+    {@"AXSearchField", u"searchTextField"_ns},
+    {@"AXSummary", u"summary"_ns},
+    {@"AXTabPanel", u"tabPanel"_ns},
+    {@"AXTerm", u"term"_ns},
+    {@"AXUserInterfaceTooltip", u"tooltip"_ns}};
+
+struct RoleDescrComparator {
+  const NSString* mRole;
+  explicit RoleDescrComparator(const NSString* aRole) : mRole(aRole) {}
+  int operator()(const RoleDescrMap& aEntry) const {
+    return [mRole compare:aEntry.role];
+  }
+};
+
+- (NSString*)moxRoleDescription {
+  if (NSString* ariaRoleDescription =
+          utils::GetAccAttr(self, nsGkAtoms::aria_roledescription)) {
+    if ([ariaRoleDescription length]) {
+      return ariaRoleDescription;
+    }
+  }
+
+  if (mRole == roles::FIGURE) return utils::LocalizedString(u"figure"_ns);
+
+  if (mRole == roles::HEADING) return utils::LocalizedString(u"heading"_ns);
+
+  if (mRole == roles::MARK) {
+    return utils::LocalizedString(u"highlight"_ns);
+  }
+
+  NSString* subrole = [self moxSubrole];
+
+  if (subrole) {
+    size_t idx = 0;
+    if (BinarySearchIf(sRoleDescrMap, 0, ArrayLength(sRoleDescrMap),
+                       RoleDescrComparator(subrole), &idx)) {
+      return utils::LocalizedString(sRoleDescrMap[idx].description);
+    }
+  }
+
+  return NSAccessibilityRoleDescription([self moxRole], subrole);
+}
+
+- (NSString*)moxLabel {
+  if ([self isExpired]) {
+    return nil;
+  }
+
+  nsAutoString name;
+
+  /* If our accessible is:
+   * 1. Named by invisible text, or
+   * 2. Has more than one labeling relation, or
+   * 3. Is a special role defined in providesLabelNotTitle
+   *   ... return its name as a label (AXDescription).
+   */
+  ENameValueFlag flag = mGeckoAccessible->Name(name);
+  if (flag == eNameFromSubtree) {
+    return nil;
+  }
+
+  if (![self providesLabelNotTitle]) {
+    NSArray* relations = [self getRelationsByType:RelationType::LABELLED_BY];
+    if ([relations count] == 1) {
+      return nil;
+    }
+  }
+
+  return nsCocoaUtils::ToNSString(name);
+}
+
+- (NSString*)moxTitle {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+
+  // In some special cases we provide the name in the label (AXDescription).
+  if ([self providesLabelNotTitle]) {
+    return nil;
+  }
+
+  nsAutoString title;
+  mGeckoAccessible->Name(title);
+  if (nsCoreUtils::IsWhitespaceString(title)) {
+    return @"";
+  }
+
+  return nsCocoaUtils::ToNSString(title);
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(nil);
+}
+
+- (id)moxValue {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+
+  nsAutoString value;
+  mGeckoAccessible->Value(value);
+
+  return nsCocoaUtils::ToNSString(value);
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(nil);
+}
+
+- (NSString*)moxHelp {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+
+  // What needs to go here is actually the accDescription of an item.
+  // The MSAA acc_help method has nothing to do with this one.
+  nsAutoString helpText;
+  mGeckoAccessible->Description(helpText);
+
+  return nsCocoaUtils::ToNSString(helpText);
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(nil);
+}
+
+- (NSWindow*)moxWindow {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+
+  // Get a pointer to the native window (NSWindow) we reside in.
+  NSWindow* nativeWindow = nil;
+  DocAccessible* docAcc = nullptr;
+  if (LocalAccessible* acc = mGeckoAccessible->AsLocal()) {
+    docAcc = acc->Document();
+  } else {
+    RemoteAccessible* proxy = mGeckoAccessible->AsRemote();
+    LocalAccessible* outerDoc = proxy->OuterDocOfRemoteBrowser();
+    if (outerDoc) docAcc = outerDoc->Document();
+  }
+
+  if (docAcc) nativeWindow = static_cast<NSWindow*>(docAcc->GetNativeWindow());
+
+  MOZ_ASSERT(nativeWindow || gfxPlatform::IsHeadless(),
+             "Couldn't get native window");
+  return nativeWindow;
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(nil);
+}
+
+- (NSNumber*)moxEnabled {
+  if ([self stateWithMask:states::UNAVAILABLE]) {
+    return @NO;
+  }
+
+  if (![self isRoot]) {
+    mozAccessible* parent = (mozAccessible*)[self moxUnignoredParent];
+    if (![parent isRoot]) {
+      return @(![parent disableChild:self]);
+    }
+  }
+
+  return @YES;
+}
+
+- (NSNumber*)moxFocused {
+  return @([self stateWithMask:states::FOCUSED] != 0);
+}
+
+- (NSNumber*)moxSelected {
+  return @NO;
+}
+
+- (NSNumber*)moxExpanded {
+  return @([self stateWithMask:states::EXPANDED] != 0);
+}
+
+- (NSValue*)moxFrame {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  LayoutDeviceIntRect rect = mGeckoAccessible->Bounds();
+  NSScreen* mainView = [[NSScreen screens] objectAtIndex:0];
+  CGFloat scaleFactor = nsCocoaUtils::GetBackingScaleFactor(mainView);
+
+  return [NSValue
+      valueWithRect:NSMakeRect(
+                        static_cast<CGFloat>(rect.x) / scaleFactor,
+                        [mainView frame].size.height -
+                            static_cast<CGFloat>(rect.y + rect.height) /
+                                scaleFactor,
+                        static_cast<CGFloat>(rect.width) / scaleFactor,
+                        static_cast<CGFloat>(rect.height) / scaleFactor)];
+}
+
+- (NSString*)moxARIACurrent {
+  if (![self stateWithMask:states::CURRENT]) {
+    return nil;
+  }
+
+  return utils::GetAccAttr(self, nsGkAtoms::aria_current);
+}
+
+- (NSNumber*)moxARIAAtomic {
+  return @(utils::GetAccAttr(self, nsGkAtoms::aria_atomic) != nil);
+}
+
+- (NSString*)moxARIALive {
+  return utils::GetAccAttr(self, nsGkAtoms::aria_live);
+}
+
+- (NSNumber*)moxARIAPosInSet {
+  GroupPos groupPos = mGeckoAccessible->GroupPosition();
+  return @(groupPos.posInSet);
+}
+
+- (NSNumber*)moxARIASetSize {
+  GroupPos groupPos = mGeckoAccessible->GroupPosition();
+  return @(groupPos.setSize);
+}
+
+- (NSString*)moxARIARelevant {
+  if (NSString* relevant =
+          utils::GetAccAttr(self, nsGkAtoms::containerRelevant)) {
+    return relevant;
+  }
+
+  // Default aria-relevant value
+  return @"additions text";
+}
+
+- (id)moxTitleUIElement {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  NSArray* relations = [self getRelationsByType:RelationType::LABELLED_BY];
+  if ([relations count] == 1) {
+    return [relations firstObject];
+  }
+
+  return nil;
+}
+
+- (NSString*)moxDOMIdentifier {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  nsAutoString id;
+  mGeckoAccessible->DOMNodeID(id);
+
+  return nsCocoaUtils::ToNSString(id);
+}
+
+- (NSNumber*)moxRequired {
+  return @([self stateWithMask:states::REQUIRED] != 0);
+}
+
+- (NSNumber*)moxElementBusy {
+  return @([self stateWithMask:states::BUSY] != 0);
+}
+
+- (NSArray*)moxLinkedUIElements {
+  return [self getRelationsByType:RelationType::FLOWS_TO];
+}
+
+- (NSArray*)moxARIAControls {
+  return [self getRelationsByType:RelationType::CONTROLLER_FOR];
+}
+
+- (mozAccessible*)topWebArea {
+  Accessible* doc = nsAccUtils::DocumentFor(mGeckoAccessible);
+  while (doc) {
+    if (doc->IsLocal()) {
+      DocAccessible* docAcc = doc->AsLocal()->AsDoc();
+      if (docAcc->DocumentNode()->GetBrowsingContext()->IsTopContent()) {
+        return GetNativeFromGeckoAccessible(docAcc);
+      }
+
+      doc = docAcc->ParentDocument();
+    } else {
+      DocAccessibleParent* docProxy = doc->AsRemote()->AsDoc();
+      if (docProxy->IsTopLevel()) {
+        return GetNativeFromGeckoAccessible(docProxy);
+      }
+      doc = docProxy->ParentDoc();
+    }
+  }
+
+  return nil;
+}
+
+- (void)handleRoleChanged:(mozilla::a11y::role)newRole {
+  mRole = newRole;
+  mARIARole = nullptr;
+
+  // For testing purposes
+  [self moxPostNotification:@"AXMozRoleChanged"];
+}
+
+- (id)moxEditableAncestor {
+  return [self moxFindAncestor:^BOOL(id moxAcc, BOOL* stop) {
+    return [moxAcc isKindOfClass:[mozTextAccessible class]];
+  }];
+}
+
+- (id)moxHighestEditableAncestor {
+  id highestAncestor = [self moxEditableAncestor];
+  while ([highestAncestor conformsToProtocol:@protocol(MOXAccessible)]) {
+    id ancestorParent = [highestAncestor moxUnignoredParent];
+    if (![ancestorParent conformsToProtocol:@protocol(MOXAccessible)]) {
+      break;
+    }
+
+    id higherAncestor = [ancestorParent moxEditableAncestor];
+
+    if (!higherAncestor) {
+      break;
+    }
+
+    highestAncestor = higherAncestor;
+  }
+
+  return highestAncestor;
+}
+
+- (id)moxFocusableAncestor {
+  // XXX: Checking focusable state up the chain can be expensive. For now,
+  // we can just return AXEditableAncestor since the main use case for this
+  // is rich text editing with links.
+  return [self moxEditableAncestor];
+}
+
+#ifndef RELEASE_OR_BETA
+- (NSString*)moxMozDebugDescription {
+  NS_OBJC_BEGIN_TRY_BLOCK_RETURN;
+
+  if (!mGeckoAccessible) {
+    return [NSString stringWithFormat:@"<%@: %p mGeckoAccessible=null>",
+                                      NSStringFromClass([self class]), self];
+  }
+
+  NSMutableString* domInfo = [NSMutableString string];
+  if (NSString* tagName = utils::GetAccAttr(self, nsGkAtoms::tag)) {
+    [domInfo appendFormat:@" %@", tagName];
+    NSString* domID = [self moxDOMIdentifier];
+    if ([domID length]) {
+      [domInfo appendFormat:@"#%@", domID];
+    }
+    if (NSString* className = utils::GetAccAttr(self, nsGkAtoms::_class)) {
+      [domInfo
+          appendFormat:@".%@",
+                       [className stringByReplacingOccurrencesOfString:@" "
+                                                            withString:@"."]];
+    }
+  }
+
+  return [NSString stringWithFormat:@"<%@: %p %@%@>",
+                                    NSStringFromClass([self class]), self,
+                                    [self moxRole], domInfo];
+
+  NS_OBJC_END_TRY_BLOCK_RETURN(nil);
+}
+#endif
+
+- (NSArray*)moxUIElementsForSearchPredicate:(NSDictionary*)searchPredicate {
+  // Create our search object and set it up with the searchPredicate
+  // params. The init function does additional parsing. We pass a
+  // reference to the web area to use as a start element if one is not
+  // specified.
+  MOXSearchInfo* search =
+      [[[MOXSearchInfo alloc] initWithParameters:searchPredicate
+                                         andRoot:self] autorelease];
+
+  return [search performSearch];
+}
+
+- (NSNumber*)moxUIElementCountForSearchPredicate:
+    (NSDictionary*)searchPredicate {
+  return [NSNumber
+      numberWithDouble:[[self moxUIElementsForSearchPredicate:searchPredicate]
+                           count]];
+}
+
+- (void)moxSetFocused:(NSNumber*)focused {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  if ([focused boolValue]) {
+    mGeckoAccessible->TakeFocus();
+  }
+}
+
+- (void)moxPerformScrollToVisible {
+  MOZ_ASSERT(mGeckoAccessible);
+  mGeckoAccessible->ScrollTo(nsIAccessibleScrollType::SCROLL_TYPE_ANYWHERE);
+}
+
+- (void)moxPerformShowMenu {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  // We don't need to convert this rect into mac coordinates because the
+  // mouse event synthesizer expects layout (gecko) coordinates.
+  LayoutDeviceIntRect bounds = mGeckoAccessible->Bounds();
+
+  LocalAccessible* rootAcc = mGeckoAccessible->IsLocal()
+                                 ? mGeckoAccessible->AsLocal()->RootAccessible()
+                                 : mGeckoAccessible->AsRemote()
+                                       ->OuterDocOfRemoteBrowser()
+                                       ->RootAccessible();
+  id objOrView =
+      GetObjectOrRepresentedView(GetNativeFromGeckoAccessible(rootAcc));
+
+  LayoutDeviceIntPoint p = LayoutDeviceIntPoint(
+      bounds.X() + (bounds.Width() / 2), bounds.Y() + (bounds.Height() / 2));
+  nsIWidget* widget = [objOrView widget];
+  widget->SynthesizeNativeMouseEvent(
+      p, nsIWidget::NativeMouseMessage::ButtonDown, MouseButton::eSecondary,
+      nsIWidget::Modifiers::NO_MODIFIERS, nullptr);
+}
+
+- (void)moxPerformPress {
+  MOZ_ASSERT(mGeckoAccessible);
+
+  mGeckoAccessible->DoAction(0);
+}
+
+#pragma mark -
+
+- (BOOL)disableChild:(mozAccessible*)child {
+  return NO;
+}
+
+- (void)maybePostLiveRegionChanged {
+  id<MOXAccessible> liveRegion =
+      [self moxFindAncestor:^BOOL(id<MOXAccessible> moxAcc, BOOL* stop) {
+        return [moxAcc moxIsLiveRegion];
+      }];
+
+  if (liveRegion) {
+    [liveRegion moxPostNotification:@"AXLiveRegionChanged"];
+  }
+}
+
+- (void)maybePostA11yUtilNotification {
+  MOZ_ASSERT(mGeckoAccessible);
+  // Sometimes we use a special live region to make announcements to the user.
+  // This region is a child of the root document, but doesn't contain any
+  // content. If we try to fire regular AXLiveRegion changed events through it,
+  // VoiceOver clips the notifications because it (rightfully) doesn't detect
+  // focus within the region. We get around this by firing an
+  // AXAnnouncementRequested notification here instead.
+  // Verify we're trying to send a notification for the a11yUtils alert (and not
+  // a random acc with the same ID) by checking:
+  //  - The gecko acc is local, our a11y-announcement lives in browser.xhtml
+  //  - The ID of the gecko acc is "a11y-announcement"
+  //  - The native acc is a direct descendent of the root
+  if (mGeckoAccessible->IsLocal() &&
+      [[self moxDOMIdentifier] isEqualToString:@"a11y-announcement"] &&
+      [[self moxParent] isKindOfClass:[mozRootAccessible class]]) {
+    // Our actual announcement should be stored as a child of the alert,
+    // so we verify a child exists, and then query that child below.
+    NSArray* children = [self moxChildren];
+    MOZ_ASSERT([children count] == 1 && children[0],
+               "A11yUtil event received, but no announcement found?");
+
+    mozAccessible* announcement = children[0];
+    NSString* key;
+    if ([announcement providesLabelNotTitle]) {
+      key = [announcement moxLabel];
+    } else {
+      key = [announcement moxTitle];
+    }
+
+    NSDictionary* info = @{
+      NSAccessibilityAnnouncementKey : key ? key : @(""),
+      NSAccessibilityPriorityKey : @(NSAccessibilityPriorityMedium)
+    };
+
+    id window = [self moxWindow];
+
+    // This sends events via nsIObserverService to be consumed by our
+    // mochitests. Normally we'd fire these events through moxPostNotification
+    // which takes care of this, but because the window we fetch above isn't
+    // derrived from MOXAccessibleBase, we do this (and post the notification)
+    // manually.
+    xpcAccessibleMacEvent::FireEvent(
+        window, NSAccessibilityAnnouncementRequestedNotification, info);
+    NSAccessibilityPostNotificationWithUserInfo(
+        window, NSAccessibilityAnnouncementRequestedNotification, info);
+  }
+}
+
+- (NSArray<mozAccessible*>*)getRelationsByType:(RelationType)relationType {
+  NSMutableArray<mozAccessible*>* relations =
+      [[[NSMutableArray alloc] init] autorelease];
+  Relation rel = mGeckoAccessible->RelationByType(relationType);
+  while (Accessible* relAcc = rel.Next()) {
+    if (mozAccessible* relNative = GetNativeFromGeckoAccessible(relAcc)) {
+      [relations addObject:relNative];
+    }
+  }
+
+  return relations;
+}
+
+- (void)handleAccessibleTextChangeEvent:(NSString*)change
+                               inserted:(BOOL)isInserted
+                            inContainer:(Accessible*)container
+                                     at:(int32_t)start {
+}
+
+- (void)handleAccessibleEvent:(uint32_t)eventType {
+  switch (eventType) {
+    case nsIAccessibleEvent::EVENT_ALERT:
+      [self maybePostA11yUtilNotification];
+      break;
+    case nsIAccessibleEvent::EVENT_FOCUS:
+      [self moxPostNotification:
+                NSAccessibilityFocusedUIElementChangedNotification];
+      break;
+    case nsIAccessibleEvent::EVENT_MENUPOPUP_START:
+      [self moxPostNotification:@"AXMenuOpened"];
+      break;
+    case nsIAccessibleEvent::EVENT_MENUPOPUP_END:
+      [self moxPostNotification:@"AXMenuClosed"];
+      break;
+    case nsIAccessibleEvent::EVENT_SELECTION:
+    case nsIAccessibleEvent::EVENT_SELECTION_ADD:
+    case nsIAccessibleEvent::EVENT_SELECTION_REMOVE:
+    case nsIAccessibleEvent::EVENT_SELECTION_WITHIN:
+      [self moxPostNotification:
+                NSAccessibilitySelectedChildrenChangedNotification];
+      break;
+    case nsIAccessibleEvent::EVENT_TEXT_CARET_MOVED: {
+      if (![self stateWithMask:states::SELECTABLE_TEXT]) {
+        break;
+      }
+      // We consider any caret move event to be a selected text change event.
+      // So dispatching an event for EVENT_TEXT_SELECTION_CHANGED would be
+      // reduntant.
+      MOXTextMarkerDelegate* delegate =
+          static_cast<MOXTextMarkerDelegate*>([self moxTextMarkerDelegate]);
+      NSMutableDictionary* userInfo =
+          [[[delegate selectionChangeInfo] mutableCopy] autorelease];
+      userInfo[@"AXTextChangeElement"] = self;
+
+      mozAccessible* webArea = [self topWebArea];
+      [webArea
+          moxPostNotification:NSAccessibilitySelectedTextChangedNotification
+                 withUserInfo:userInfo];
+      [self moxPostNotification:NSAccessibilitySelectedTextChangedNotification
+                   withUserInfo:userInfo];
+      break;
+    }
+    case nsIAccessibleEvent::EVENT_LIVE_REGION_ADDED:
+      mIsLiveRegion = true;
+      [self moxPostNotification:@"AXLiveRegionCreated"];
+      break;
+    case nsIAccessibleEvent::EVENT_LIVE_REGION_REMOVED:
+      mIsLiveRegion = false;
+      break;
+    case nsIAccessibleEvent::EVENT_REORDER:
+      [self maybePostLiveRegionChanged];
+      break;
+    case nsIAccessibleEvent::EVENT_NAME_CHANGE: {
+      if (![self providesLabelNotTitle]) {
+        [self moxPostNotification:NSAccessibilityTitleChangedNotification];
+      }
+      [self maybePostLiveRegionChanged];
+      break;
+    }
+  }
+}
+
+- (void)expire {
+  NS_OBJC_BEGIN_TRY_IGNORE_BLOCK;
+
+  mGeckoAccessible = nullptr;
+
+  [self moxPostNotification:NSAccessibilityUIElementDestroyedNotification];
+
+  NS_OBJC_END_TRY_IGNORE_BLOCK;
+}
+
+- (BOOL)isExpired {
+  return !mGeckoAccessible;
+}
+
+@end