Issue #3011 - Part 1: Add As{Text|Html}Editor() and AsEditorBase()

This adds helper functions to get specific types of content editors (if
possible) through the nsIEditor interface, as opposed to doing manual
casting and the ad hoc `GetHTMLEditor()` function.

Helper functions are spread out over multiple headers due to the
circular dependency issues that would be triggered otherwise.

dom/base/nsINode.cpp

@@ -16,6 +16,7 @@
 #include "mozilla/CORSMode.h"
 #include "mozilla/EventDispatcher.h"
 #include "mozilla/EventListenerManager.h"
+#include "mozilla/HTMLEditor.h"
 #include "mozilla/InternalMutationEvent.h"
 #include "mozilla/Likely.h"
 #include "mozilla/MemoryReporting.h"

editor/libeditor/EditorBase.cpp

@@ -142,6 +142,7 @@ EditorBase::EditorBase()
   , mDispatchInputEvent(true)
   , mIsInEditAction(false)
   , mHidingCaret(false)
+  , mIsHTMLEditorClass(false)
 {
 }
 

editor/libeditor/EditorBase.h

@@ -114,6 +114,7 @@ class DeleteNodeTransaction;
 class DeleteTextTransaction;
 class EditAggregateTransaction;
 class ErrorResult;
+class HTMLEditor;
 class InsertNodeTransaction;
 class InsertTextTransaction;
 class JoinNodeTransaction;
@@ -121,6 +122,7 @@ class PlaceholderTransaction;
 class RemoveStyleSheetTransaction;
 class SplitNodeTransaction;
 class TextComposition;
+class TextEditor;
 struct EditorDOMPoint;
 
 namespace dom {
@@ -1113,14 +1115,32 @@ protected:
   bool mIsInEditAction;
   // Whether caret is hidden forcibly.
   bool mHidingCaret;
+  // Whether we are an HTML editor class.
+  bool mIsHTMLEditorClass;
 
   friend bool NSCanUnload(nsISupports* serviceMgr);
   friend class AutoRules;
   friend class AutoSelectionRestorer;
   friend class AutoTransactionsConserveSelection;
   friend class RangeUpdater;
+  friend class nsIEditor;
 };
 
 } // namespace mozilla
 
+// nsIEditor helper functions.
+// Here because of code context.
+mozilla::EditorBase*
+nsIEditor::AsEditorBase()
+{
+  return static_cast<mozilla::EditorBase*>(this);
+}
+
+const mozilla::EditorBase*
+nsIEditor::AsEditorBase() const
+{
+  return static_cast<const mozilla::EditorBase*>(this);
+}
+
+
 #endif // #ifndef mozilla_EditorBase_h

editor/libeditor/HTMLEditRules.cpp

@@ -233,9 +233,16 @@ NS_IMPL_CYCLE_COLLECTION_INHERITED(HTMLEditRules, TextEditRules,
 NS_IMETHODIMP
 HTMLEditRules::Init(TextEditor* aTextEditor)
 {
+  if (NS_WARN_IF(!aTextEditor)) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
   InitFields();
 
-  mHTMLEditor = static_cast<HTMLEditor*>(aTextEditor);
+  mHTMLEditor = aTextEditor->AsHTMLEditor();
+  if (NS_WARN_IF(!mHTMLEditor)) {
+    return NS_ERROR_INVALID_ARG;
+  }
 
   // call through to base class Init
   nsresult rv = TextEditRules::Init(aTextEditor);

editor/libeditor/HTMLEditor.cpp

@@ -132,6 +132,7 @@ HTMLEditor::HTMLEditor()
   , mPositionedObjectBorderTop(0)
   , mGridSize(0)
 {
+  mIsHTMLEditorClass = true;
 }
 
 HTMLEditor::~HTMLEditor()
@@ -501,7 +502,7 @@ HTMLEditor::InitRules()
     // instantiate the rules for the html editor
     mRules = new HTMLEditRules();
   }
-  return mRules->Init(static_cast<TextEditor*>(this));
+  return mRules->Init(this);
 }
 
 NS_IMETHODIMP

editor/libeditor/HTMLEditor.h

@@ -1108,4 +1108,20 @@ private:
 
 } // namespace mozilla
 
+// nsIEditor helper functions.
+// Here because of code context.
+mozilla::HTMLEditor*
+nsIEditor::AsHTMLEditor()
+{
+  return static_cast<mozilla::EditorBase*>(this)->mIsHTMLEditorClass ?
+           static_cast<mozilla::HTMLEditor*>(this) : nullptr;
+}
+
+const mozilla::HTMLEditor*
+nsIEditor::AsHTMLEditor() const
+{
+  return static_cast<const mozilla::EditorBase*>(this)->mIsHTMLEditorClass ?
+           static_cast<const mozilla::HTMLEditor*>(this) : nullptr;
+}
+
 #endif // #ifndef mozilla_HTMLEditor_h

editor/libeditor/HTMLEditorEventListener.cpp

@@ -30,24 +30,18 @@ namespace mozilla {
 
 using namespace dom;
 
-#ifdef DEBUG
 nsresult
 HTMLEditorEventListener::Connect(EditorBase* aEditorBase)
 {
-  nsCOMPtr<nsIHTMLEditor> htmlEditor = do_QueryObject(aEditorBase);
-  nsCOMPtr<nsIHTMLInlineTableEditor> htmlInlineTableEditor =
-    do_QueryObject(aEditorBase);
-  NS_PRECONDITION(htmlEditor && htmlInlineTableEditor,
-                  "Set HTMLEditor or its sub class");
-  return EditorEventListener::Connect(aEditorBase);
-}
-#endif
-
-HTMLEditor*
-HTMLEditorEventListener::GetHTMLEditor()
-{
-  // mEditor must be HTMLEditor or its subclass.
-  return static_cast<HTMLEditor*>(mEditorBase);
+  if (NS_WARN_IF(!aEditorBase)) {
+    return NS_ERROR_INVALID_ARG;
+  }
+  // Guarantee that mEditorBase is always HTMLEditor.
+  HTMLEditor* htmlEditor = aEditorBase->AsHTMLEditor();
+  if (NS_WARN_IF(!htmlEditor)) {
+    return NS_ERROR_INVALID_ARG;
+  }
+  return EditorEventListener::Connect(htmlEditor);
 }
 
 nsresult
@@ -59,7 +53,8 @@ HTMLEditorEventListener::MouseUp(nsIDOMMouseEvent* aMouseEvent)
 
   // FYI: We need to notify HTML editor of mouseup even if it's consumed
   //      because HTML editor always needs to release grabbing resizer.
-  HTMLEditor* htmlEditor = GetHTMLEditor();
+  HTMLEditor* htmlEditor = mEditorBase->AsHTMLEditor();
+  MOZ_ASSERT(htmlEditor);
 
   nsCOMPtr<nsIDOMEventTarget> target;
   nsresult rv = aMouseEvent->AsEvent()->GetTarget(getter_AddRefs(target));
@@ -85,7 +80,9 @@ HTMLEditorEventListener::MouseDown(nsIDOMMouseEvent* aMouseEvent)
   WidgetMouseEvent* mousedownEvent =
     aMouseEvent->AsEvent()->WidgetEventPtr()->AsMouseEvent();
 
-  HTMLEditor* htmlEditor = GetHTMLEditor();
+  HTMLEditor* htmlEditor = mEditorBase->AsHTMLEditor();
+  MOZ_ASSERT(htmlEditor);
+
   // Contenteditable should disregard mousedowns outside it.
   // IsAcceptableInputEvent() checks it for a mouse event.
   if (!htmlEditor->IsAcceptableInputEvent(mousedownEvent)) {
@@ -221,13 +218,19 @@ HTMLEditorEventListener::MouseDown(nsIDOMMouseEvent* aMouseEvent)
 nsresult
 HTMLEditorEventListener::MouseClick(nsIDOMMouseEvent* aMouseEvent)
 {
+  if (NS_WARN_IF(DetachedFromEditor())) {
+    return NS_OK;
+  }
+
   nsCOMPtr<nsIDOMEventTarget> target;
   nsresult rv = aMouseEvent->AsEvent()->GetTarget(getter_AddRefs(target));
   NS_ENSURE_SUCCESS(rv, rv);
   NS_ENSURE_TRUE(target, NS_ERROR_NULL_POINTER);
   nsCOMPtr<nsIDOMElement> element = do_QueryInterface(target);
 
-  GetHTMLEditor()->DoInlineTableEditingAction(element);
+  HTMLEditor* htmlEditor = mEditorBase->AsHTMLEditor();
+  MOZ_ASSERT(htmlEditor);
+  htmlEditor->DoInlineTableEditingAction(element);
 
   return EditorEventListener::MouseClick(aMouseEvent);
 }

editor/libeditor/HTMLEditorEventListener.h

@@ -25,17 +25,13 @@ public:
   {
   }
 
-#ifdef DEBUG
-  // WARNING: You must be use HTMLEditor or its sub class for this class.
+  // Connect() fails if aEditorBase isn't an HTMLEditor instance.
   virtual nsresult Connect(EditorBase* aEditorBase) override;
-#endif
 
 protected:
   virtual nsresult MouseDown(nsIDOMMouseEvent* aMouseEvent) override;
   virtual nsresult MouseUp(nsIDOMMouseEvent* aMouseEvent) override;
   virtual nsresult MouseClick(nsIDOMMouseEvent* aMouseEvent) override;
-
-  inline HTMLEditor* GetHTMLEditor();
 };
 
 } // namespace mozilla

editor/libeditor/TextEditor.cpp

@@ -10,6 +10,7 @@
 #include "gfxFontUtils.h"
 #include "mozilla/Assertions.h"
 #include "mozilla/EditorUtils.h" // AutoEditBatch, AutoRules
+#include "mozilla/HTMLEditor.h"
 #include "mozilla/mozalloc.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/TextEditRules.h"

editor/libeditor/TextEditor.h

@@ -247,4 +247,18 @@ protected:
 
 } // namespace mozilla
 
+// nsIEditor helper functions.
+// Here because of code context.
+mozilla::TextEditor*
+nsIEditor::AsTextEditor()
+{
+  return static_cast<mozilla::TextEditor*>(this);
+}
+
+const mozilla::TextEditor*
+nsIEditor::AsTextEditor() const
+{
+  return static_cast<const mozilla::TextEditor*>(this);
+}
+
 #endif // #ifndef mozilla_TextEditor_h

editor/nsIEditor.idl

@@ -21,6 +21,14 @@ interface nsIEditActionListener;
 interface nsIInlineSpellChecker;
 interface nsITransferable;
 
+%{C++
+namespace mozilla {
+class EditorBase;
+class HTMLEditor;
+class TextEditor;
+} // namespace mozilla
+%}
+ 
 [scriptable, uuid(094be624-f0bf-400f-89e2-6a84baab9474)]
 interface nsIEditor  : nsISupports
 {
@@ -564,4 +572,34 @@ interface nsIEditor  : nsISupports
    * or nsIEditorObserver::CancelEditAction().  Otherwise, false.
    */
   [noscript] readonly attribute boolean isInEditAction;
+
+%{C++
+  /**
+   * AsEditorBase() returns a pointer to EditorBase class.
+   *
+   * In order to avoid circular dependency issues, this method is defined
+   * in mozilla/EditorBase.h.  Consumers need to #include that header.
+   */
+  inline mozilla::EditorBase* AsEditorBase();
+  inline const mozilla::EditorBase* AsEditorBase() const;
+
+  /**
+   * AsTextEditor() returns a pointer to TextEditor class.
+   *
+   * In order to avoid circular dependency issues, this method is defined
+   * in mozilla/TextEditor.h.  Consumers need to #include that header.
+   */
+  inline mozilla::TextEditor* AsTextEditor();
+  inline const mozilla::TextEditor* AsTextEditor() const;
+
+  /**
+   * AsHTMLEditor() returns a pointer to HTMLEditor class.
+   *
+   * In order to avoid circular dependency issues, this method is defined
+   * in mozilla/HTMLEditor.h.  Consumers need to #include that header.
+   */
+  inline mozilla::HTMLEditor* AsHTMLEditor();
+  inline const mozilla::HTMLEditor* AsHTMLEditor() const;
+%}
+
 };