Bug 1874040 - Simplify dir=auto implementation. r=smaug

Make sure to do no work on insertions if the dir=auto element has
already the right strong directionality, but record that the node might
be the one impacting the dir=auto resolution.

Also get some node flags back.

Differential Revision: https://phabricator.services.mozilla.com/D202071

dom/base/DirectionalityUtils.h

@@ -18,6 +18,7 @@ class nsTextNode;
 namespace mozilla::dom {
 class Element;
 class HTMLSlotElement;
+struct UnbindContext;
 }  // namespace mozilla::dom
 
 namespace mozilla {
@@ -133,10 +134,8 @@ void SetDirectionFromNewTextNode(nsTextNode* aTextNode);
 /**
  * When a text node is removed from a document, find any ancestors whose
  * directionality it determined and redetermine their directionality
- *
- * @param aTextNode the text node
  */
-void ResetDirectionSetByTextNode(nsTextNode* aTextNode);
+void ResetDirectionSetByTextNode(nsTextNode*, dom::UnbindContext&);
 
 /**
  * Set the directionality of an element according to the directionality of the

dom/base/Element.cpp

@@ -3436,14 +3436,6 @@ nsresult Element::PostHandleEventForLinks(EventChainPostVisitor& aVisitor) {
 
 void Element::GetLinkTarget(nsAString& aTarget) { aTarget.Truncate(); }
 
-static nsStaticAtom* const sPropertiesToTraverseAndUnlink[] = {
-    nsGkAtoms::dirAutoSetBy, nullptr};
-
-// static
-nsStaticAtom* const* Element::HTMLSVGPropertiesToTraverseAndUnlink() {
-  return sPropertiesToTraverseAndUnlink;
-}
-
 nsresult Element::CopyInnerTo(Element* aDst, ReparseAttributes aReparse) {
   nsresult rv = aDst->mAttrs.EnsureCapacityToClone(mAttrs);
   NS_ENSURE_SUCCESS(rv, rv);

dom/base/Element.h

@@ -1111,8 +1111,6 @@ class Element : public FragmentOrElement {
     return FindAttributeDependence(aAttribute, aMaps, N);
   }
 
-  static nsStaticAtom* const* HTMLSVGPropertiesToTraverseAndUnlink();
-
   MOZ_CAN_RUN_SCRIPT virtual void HandleInvokeInternal(nsAtom* aAction,
                                                        ErrorResult& aRv) {}
 

dom/base/FragmentOrElement.cpp

@@ -1327,14 +1327,6 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(FragmentOrElement)
       Element* elem = tmp->AsElement();
       elem->UnlinkIntersectionObservers();
     }
-
-    if (tmp->IsHTMLElement() || tmp->IsSVGElement()) {
-      nsStaticAtom* const* props =
-          Element::HTMLSVGPropertiesToTraverseAndUnlink();
-      for (uint32_t i = 0; props[i]; ++i) {
-        tmp->RemoveProperty(props[i]);
-      }
-    }
   }
 
   // Unlink child content (and unbind our subtree).
@@ -1805,15 +1797,6 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(FragmentOrElement)
         }
       }
     }
-    if (tmp->IsHTMLElement() || tmp->IsSVGElement()) {
-      nsStaticAtom* const* props =
-          Element::HTMLSVGPropertiesToTraverseAndUnlink();
-      for (uint32_t i = 0; props[i]; ++i) {
-        nsISupports* property =
-            static_cast<nsISupports*>(tmp->GetProperty(props[i]));
-        cb.NoteXPCOMChild(property);
-      }
-    }
   }
   if (tmp->IsElement()) {
     Element* element = tmp->AsElement();

dom/base/UnbindContext.h

@@ -19,11 +19,15 @@ struct MOZ_STACK_CLASS UnbindContext final {
   nsINode& Root() const { return mRoot; }
   // Whether we're the root of the subtree being unbound.
   bool IsUnbindRoot(const nsINode* aNode) const { return &mRoot == aNode; }
+  // The parent node of the subtree we're unbinding from.
+  nsINode* GetOriginalSubtreeParent() const { return mOriginalParent; }
 
-  explicit UnbindContext(nsINode& aRoot) : mRoot(aRoot) {}
+  explicit UnbindContext(nsINode& aRoot)
+      : mRoot(aRoot), mOriginalParent(aRoot.GetParentNode()) {}
 
  private:
   nsINode& mRoot;
+  nsINode* const mOriginalParent;
 };
 
 }  // namespace mozilla::dom

dom/base/nsINode.h

@@ -1895,13 +1895,9 @@ class nsINode : public mozilla::dom::EventTarget {
     // flags, because we can't use those to distinguish
     // <bdi dir="some-invalid-value"> and <bdi dir="auto">.
     NodeHasValidDirAttribute,
-    // Set if the node has dir=auto and has a property pointing to the text
-    // node that determines its direction
-    NodeHasDirAutoSet,
-    // Set if the node is a text node descendant of a node with dir=auto
-    // and has a TextNodeDirectionalityMap property listing the elements whose
-    // direction it determines.
-    NodeHasTextNodeDirectionalityMap,
+    // Set if this node, which must be a text node, might be responsible for
+    // setting the directionality of a dir="auto" ancestor.
+    NodeMaySetDirAuto,
     // Set if a node in the node's parent chain has dir=auto.
     NodeAncestorHasDirAuto,
     // Set if the node is handling a click.
@@ -2028,31 +2024,19 @@ class nsINode : public mozilla::dom::EventTarget {
   void SetHasValidDir() { SetBoolFlag(NodeHasValidDirAttribute); }
   void ClearHasValidDir() { ClearBoolFlag(NodeHasValidDirAttribute); }
   bool HasValidDir() const { return GetBoolFlag(NodeHasValidDirAttribute); }
-  void SetHasDirAutoSet() {
-    MOZ_ASSERT(NodeType() != TEXT_NODE, "SetHasDirAutoSet on text node");
-    SetBoolFlag(NodeHasDirAutoSet);
+  void SetMaySetDirAuto() {
+    // FIXME(bug 1881225): dir=auto should probably work on CDATA too.
+    MOZ_ASSERT(NodeType() == TEXT_NODE);
+    SetBoolFlag(NodeMaySetDirAuto);
   }
-  void ClearHasDirAutoSet() {
-    MOZ_ASSERT(NodeType() != TEXT_NODE, "ClearHasDirAutoSet on text node");
-    ClearBoolFlag(NodeHasDirAutoSet);
+  bool MaySetDirAuto() const {
+    MOZ_ASSERT(NodeType() == TEXT_NODE);
+    return GetBoolFlag(NodeMaySetDirAuto);
   }
-  bool HasDirAutoSet() const { return GetBoolFlag(NodeHasDirAutoSet); }
-  void SetHasTextNodeDirectionalityMap() {
-    MOZ_ASSERT(NodeType() == TEXT_NODE,
-               "SetHasTextNodeDirectionalityMap on non-text node");
-    SetBoolFlag(NodeHasTextNodeDirectionalityMap);
+  void ClearMaySetDirAuto() {
+    MOZ_ASSERT(NodeType() == TEXT_NODE);
+    ClearBoolFlag(NodeMaySetDirAuto);
   }
-  void ClearHasTextNodeDirectionalityMap() {
-    MOZ_ASSERT(NodeType() == TEXT_NODE,
-               "ClearHasTextNodeDirectionalityMap on non-text node");
-    ClearBoolFlag(NodeHasTextNodeDirectionalityMap);
-  }
-  bool HasTextNodeDirectionalityMap() const {
-    MOZ_ASSERT(NodeType() == TEXT_NODE,
-               "HasTextNodeDirectionalityMap on non-text node");
-    return GetBoolFlag(NodeHasTextNodeDirectionalityMap);
-  }
-
   void SetAncestorHasDirAuto() { SetBoolFlag(NodeAncestorHasDirAuto); }
   void ClearAncestorHasDirAuto() { ClearBoolFlag(NodeAncestorHasDirAuto); }
   bool AncestorHasDirAuto() const {

dom/base/nsTextNode.cpp

@@ -43,13 +43,13 @@ class nsAttributeTextNode final : public nsTextNode,
     NS_ASSERTION(mAttrName, "Must have attr name");
   }
 
-  virtual nsresult BindToTree(BindContext&, nsINode& aParent) override;
-  virtual void UnbindFromTree(UnbindContext&) override;
+  nsresult BindToTree(BindContext&, nsINode& aParent) override;
+  void UnbindFromTree(UnbindContext&) override;
 
   NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
   NS_DECL_NSIMUTATIONOBSERVER_NODEWILLBEDESTROYED
 
-  virtual already_AddRefed<CharacterData> CloneDataNode(
+  already_AddRefed<CharacterData> CloneDataNode(
       mozilla::dom::NodeInfo* aNodeInfo, bool aCloneText) const override {
     RefPtr<nsAttributeTextNode> it =
         new (aNodeInfo->NodeInfoManager()) nsAttributeTextNode(
@@ -124,8 +124,8 @@ nsresult nsTextNode::BindToTree(BindContext& aContext, nsINode& aParent) {
 }
 
 void nsTextNode::UnbindFromTree(UnbindContext& aContext) {
-  ResetDirectionSetByTextNode(this);
   CharacterData::UnbindFromTree(aContext);
+  ResetDirectionSetByTextNode(this, aContext);
 }
 
 #ifdef MOZ_DOM_LIST

testing/web-platform/meta/html/dom/elements/global-attributes/dir-assorted.window.js.ini

@@ -8,9 +8,6 @@
   [Non-HTML element text contents influence dir=auto]
     expected: FAIL
 
-  [text changes apply to dir=auto on further ancestor after removing dir=auto from closer ancestor]
-    expected: FAIL
-
   [directionality of bdi elements: dir=auto empty in rtl parent]
     expected: FAIL
 

testing/web-platform/meta/html/dom/elements/global-attributes/dir-auto-dynamic-changes.window.js.ini

@@ -1,16 +1,10 @@
 [dir-auto-dynamic-changes.window.html]
-  [dir=auto changes for content insertion and removal, in and out of document]
-    expected: FAIL
-
   [dir=auto changes for slot reassignment]
     expected: FAIL
 
   [text changes affecting both slot and ancestor with dir=auto]
     expected: FAIL
 
-  [dynamic changes to subtrees excluded as a result of the dir attribute]
-    expected: FAIL
-
   [dynamic changes inside of non-HTML elements]
     expected: FAIL
 

xpcom/ds/StaticAtoms.py

@@ -342,7 +342,6 @@ STATIC_ATOMS = [
     Atom("difference", "difference"),
     Atom("digit", "digit"),
     Atom("dir", "dir"),
-    Atom("dirAutoSetBy", "dirAutoSetBy"),
     Atom("directory", "directory"),
     Atom("dirname", "dirname"),
     Atom("disableOutputEscaping", "disable-output-escaping"),
@@ -1236,7 +1235,6 @@ STATIC_ATOMS = [
     Atom("textarea", "textarea"),
     Atom("textbox", "textbox"),
     Atom("textLink", "text-link"),
-    Atom("textNodeDirectionalityMap", "textNodeDirectionalityMap"),
     Atom("textOverlay", "text-overlay"),
     Atom("tfoot", "tfoot"),
     Atom("th", "th"),