[InputEvent] Support |deleteByDrag|, |insertFromDrop| and fire in sequential order

third_party/WebKit/Source/core/page/DragController.cpp

Index: third_party/WebKit/Source/core/page/DragController.cpp
diff --git a/third_party/WebKit/Source/core/page/DragController.cpp b/third_party/WebKit/Source/core/page/DragController.cpp
index 70e4290a77a1b481e6320b4fce4f54f1837486a4..296f88e4d52f5f188edead036c4e0001f19cdabc 100644
--- a/third_party/WebKit/Source/core/page/DragController.cpp
+++ b/third_party/WebKit/Source/core/page/DragController.cpp
@@ -92,6 +92,96 @@
 
 namespace blink {
 
+namespace {
+
+DataTransfer* createDraggingDataTransfer(DataTransferAccessPolicy policy, DragData* dragData)
+{
+    return DataTransfer::create(DataTransfer::DragAndDrop, policy, dragData->platformData());
+}
+
+DocumentFragment* documentFragmentFromDragData(DragData* dragData, LocalFrame* frame, Range* context, bool allowPlainText, bool& chosePlainText)
+{
+    DCHECK(dragData);
+    chosePlainText = false;
+
+    Document& document = context->ownerDocument();
+    if (dragData->containsCompatibleContent()) {
+        if (DocumentFragment* fragment = dragData->asFragment(frame))
+            return fragment;
+
+        if (dragData->containsURL(DragData::DoNotConvertFilenames)) {
+            String title;
+            String url = dragData->asURL(DragData::DoNotConvertFilenames, &title);
+            if (!url.isEmpty()) {
+                HTMLAnchorElement* anchor = HTMLAnchorElement::create(document);
+                anchor->setHref(AtomicString(url));
+                if (title.isEmpty()) {
+                    // Try the plain text first because the url might be normalized or escaped.
+                    if (dragData->containsPlainText())
+                        title = dragData->asPlainText();
+                    if (title.isEmpty())
+                        title = url;
+                }
+                Node* anchorText = document.createTextNode(title);
+                anchor->appendChild(anchorText);
+                DocumentFragment* fragment = document.createDocumentFragment();
+                fragment->appendChild(anchor);
+                return fragment;
+            }
+        }
+    }
+    if (allowPlainText && dragData->containsPlainText()) {
+        chosePlainText = true;
+        return createFragmentFromText(EphemeralRange(context), dragData->asPlainText());
+    }
+
+    return nullptr;
+}
+
+bool doDeleteByDragWithEvents(Element* dragTarget, bool smartDelete, const Position& referenceMovePosition)

[yosin_UTC9, 2016/09/28 04:19:03]

Please add comment about |bool| return value.

[chongz, 2016/09/29 02:36:22]

Done.

+{

[yosin_UTC9, 2016/09/28 04:19:03]

This function should be in Editor class and avoid to use |bool| parameter.

[chongz, 2016/09/29 02:36:22]

Done.

+    if (!dragTarget || !dragTarget->isConnected())
+        return true;
+
+    LocalFrame* dragFrame = dragTarget->document().frame();
+
+    // Dispatch 'beforeinput'.
+    const bool shouldDelete = dispatchBeforeInputEditorCommand(dragTarget, InputEvent::InputType::DeleteByDrag, nullptr) == DispatchEventResult::NotCanceled;

[yosin_UTC9, 2016/09/28 04:19:03]

I think we should dispatch event to drag source rather than drag target since
deletion is occurred at drag source rather than drag target.

[chongz, 2016/09/29 02:36:22]

Sorry for the confusion, I've renamed it to |dragSource|.

The naming story is I have 2 event targets |dragTarget| and |dropTarget|, where
|dragTarget| is essentially the event target of the "Drag" operation (i.g.
Source of Drag&Drop).

+
+    // 'beforeinput' event handler may destroy frame, return false to cancel remaining actions;
+    if (dragFrame != dragTarget->document().frame())
+        return false;
+
+    if (shouldDelete && dragTarget->isConnected())
+        dragFrame->editor().deleteSelectionWithSmartDelete(smartDelete, InputEvent::InputType::DeleteByDrag, referenceMovePosition);
+
+    return true;
+}
+
+bool doInsertFromDropWithEvents(Element* dropTarget, DragData* dragData, DocumentFragment* fragment, Range* dropCaretRange, bool smartInsert, bool chosePlainText)

[yosin_UTC9, 2016/09/28 04:19:03]

Please add comment about |bool| return value.

[chongz, 2016/09/29 02:36:22]

Done.

+{

[yosin_UTC9, 2016/09/28 04:19:03]

This function should be in Editor class and avoid to use |bool| parameter.

[chongz, 2016/09/29 02:36:22]

Done.

+    if (!dropTarget || !dropTarget->isConnected())
+        return true;
+
+    LocalFrame* dropFrame = dropTarget->document().frame();
+
+    // Dispatch 'beforeinput'.
+    DataTransfer* dataTransfer = createDraggingDataTransfer(DataTransferReadable, dragData);
+    dataTransfer->setSourceOperation(dragData->draggingSourceOperationMask());
+    const bool shouldInsert = dispatchBeforeInputDataTransfer(dropTarget, InputEvent::InputType::InsertFromDrop, dataTransfer, nullptr) == DispatchEventResult::NotCanceled;
+
+    // 'beforeinput' event handler may destroy frame, return false to cancel remaining actions;
+    if (dropFrame != dropTarget->document().frame())
+        return false;
+
+    if (shouldInsert && dropTarget->isConnected())
+        dropFrame->editor().replaceSelectionAfterDragging(fragment, smartInsert, chosePlainText);
+
+    return true;
+}
+
+} // anonymous namespace
+
 const int DragController::DragIconRightInset = 7;
 const int DragController::DragIconBottomInset = 3;
 
@@ -124,11 +214,6 @@ static PlatformMouseEvent createMouseEvent(DragData* dragData)
         PlatformMouseEvent::RealOrIndistinguishable, monotonicallyIncreasingTime());
 }
 
-static DataTransfer* createDraggingDataTransfer(DataTransferAccessPolicy policy, DragData* dragData)
-{
-    return DataTransfer::create(DataTransfer::DragAndDrop, policy, dragData->platformData());
-}
-
 DragController::DragController(Page* page)
     : m_page(page)
     , m_documentUnderMouse(nullptr)
@@ -145,45 +230,6 @@ DragController* DragController::create(Page* page)
     return new DragController(page);
 }
 
-static DocumentFragment* documentFragmentFromDragData(DragData* dragData, LocalFrame* frame, Range* context, bool allowPlainText, bool& chosePlainText)
-{
-    ASSERT(dragData);
-    chosePlainText = false;
-
-    Document& document = context->ownerDocument();
-    if (dragData->containsCompatibleContent()) {
-        if (DocumentFragment* fragment = dragData->asFragment(frame))
-            return fragment;
-
-        if (dragData->containsURL(DragData::DoNotConvertFilenames)) {
-            String title;
-            String url = dragData->asURL(DragData::DoNotConvertFilenames, &title);
-            if (!url.isEmpty()) {
-                HTMLAnchorElement* anchor = HTMLAnchorElement::create(document);
-                anchor->setHref(AtomicString(url));
-                if (title.isEmpty()) {
-                    // Try the plain text first because the url might be normalized or escaped.
-                    if (dragData->containsPlainText())
-                        title = dragData->asPlainText();
-                    if (title.isEmpty())
-                        title = url;
-                }
-                Node* anchorText = document.createTextNode(title);
-                anchor->appendChild(anchorText);
-                DocumentFragment* fragment = document.createDocumentFragment();
-                fragment->appendChild(anchor);
-                return fragment;
-            }
-        }
-    }
-    if (allowPlainText && dragData->containsPlainText()) {
-        chosePlainText = true;
-        return createFragmentFromText(EphemeralRange(context), dragData->asPlainText());
-    }
-
-    return nullptr;
-}
-
 bool DragController::dragIsMove(FrameSelection& selection, DragData* dragData)
 {
     return m_documentUnderMouse == m_dragInitiator && selection.isContentEditable() && selection.isRange() && !isCopyKeyDown(dragData);
@@ -513,13 +559,23 @@ bool DragController::concludeEditDrag(DragData* dragData)
         if (dragIsMove(innerFrame->selection(), dragData)) {
             // NSTextView behavior is to always smart delete on moving a selection,
             // but only to smart insert if the selection granularity is word granularity.
-            bool smartDelete = innerFrame->editor().smartInsertDeleteEnabled();
-            bool smartInsert = smartDelete && innerFrame->selection().granularity() == WordGranularity && dragData->canSmartReplace();
-            innerFrame->editor().moveSelectionAfterDragging(fragment, dragCaret.base(), smartInsert, smartDelete);
+            const bool smartDelete = innerFrame->editor().smartInsertDeleteEnabled();
+            const bool smartInsert = smartDelete && innerFrame->selection().granularity() == WordGranularity && dragData->canSmartReplace();
+
+            if (!doDeleteByDragWithEvents(innerFrame->editor().findEventTargetFromSelection(), smartDelete, dragCaret.base()))
+                return false;
+
+            innerFrame->selection().setSelection(VisibleSelection(range->startPosition(), range->endPosition()));
+            if (innerFrame->selection().isAvailable()) {
+                DCHECK(m_documentUnderMouse);
+                if (!doInsertFromDropWithEvents(element, dragData, fragment, range, smartInsert, chosePlainText))
+                    return false;
+            }
         } else {
             if (setSelectionToDragCaret(innerFrame, dragCaret, range, point)) {
-                ASSERT(m_documentUnderMouse);
-                m_documentUnderMouse->frame()->editor().replaceSelectionAfterDragging(fragment, dragData->canSmartReplace(), chosePlainText);
+                DCHECK(m_documentUnderMouse);
+                if (!doInsertFromDropWithEvents(element, dragData, fragment, range, dragData->canSmartReplace(), chosePlainText))
+                    return false;
             }
         }
     } else {
@@ -530,8 +586,9 @@ bool DragController::concludeEditDrag(DragData* dragData)
         if (setSelectionToDragCaret(innerFrame, dragCaret, range, point)) {
             const bool canSmartReplace = false;
             const bool chosePlainText = true;
-            ASSERT(m_documentUnderMouse);
-            m_documentUnderMouse->frame()->editor().replaceSelectionAfterDragging(createFragmentFromText(EphemeralRange(range), text), canSmartReplace, chosePlainText);
+            DCHECK(m_documentUnderMouse);
+            if (!doInsertFromDropWithEvents(element, dragData, createFragmentFromText(EphemeralRange(range), text), range, canSmartReplace, chosePlainText))
+                return false;
         }
     }