Changeset 294714 in webkit

Timestamp:

May 23, 2022, 7:06:58 PM (4 years ago)

Author:

Wenson Hsieh

Message:

Breaking out of a quoted reply block by inserting a new paragraph should reset writing direction
​https://bugs.webkit.org/show_bug.cgi?id=240778
rdar://14839536

Reviewed by Devin Rousso.

The process of breaking out of a blockquote via the "InsertNewlineInQuotedContent" editor command currently works by
splitting the blockquote into two sibling elements underneath the same parent container, and then inserting a br
element in between these sibling blockquote elements. The selection is then moved to the end of the newly created
br, which inherits the writing direction (dir) of the element containing the blockquote. In the case of Mail, if
the system language is right-to-left but the quoted content is left-to-right, this can lead to some unintuitive behavior
when breaking out of quoted LTR content, since the newly created line break will inherit the right-to-left direction of
its ancestor.

To fix this, in the case where we're breaking out of a blockquote and the start of the selection is left-to-right but
the element that contains the blockquote is right-to-left, we can wrap the br in another block-level container
element with dir=auto to avoid inheriting the writing direction from the blockquote's ancestor. This means that the
writing direction of the newly inserted paragraph will automatically be determined by what the user types.

Test: editing/execCommand/reset-direction-after-breaking-blockquote.html

• LayoutTests/editing/execCommand/reset-direction-after-breaking-blockquote-expected.txt: Added.
• LayoutTests/editing/execCommand/reset-direction-after-breaking-blockquote.html: Added.
• Source/WebCore/editing/BreakBlockquoteCommand.cpp:

(WebCore::BreakBlockquoteCommand::doApply):

Canonical link: ​https://commits.webkit.org/250901@main

Location:

trunk

Files:

• LayoutTests/editing/execCommand/reset-direction-after-breaking-blockquote-expected.txt (added)
• LayoutTests/editing/execCommand/reset-direction-after-breaking-blockquote.html (added)
• Source/WebCore/editing/BreakBlockquoteCommand.cpp (modified) (2 diffs)

trunk/Source/WebCore/editing/BreakBlockquoteCommand.cpp

@@ -27 +27 @@
 #include "BreakBlockquoteCommand.h"
 
+#include "CommonAtomStrings.h"
 #include "Editing.h"
 #include "ElementInlines.h"
 #include "HTMLBRElement.h"
+#include "HTMLDivElement.h"
 #include "HTMLNames.h"
+#include "NodeRenderStyle.h"
 #include "NodeTraversal.h"
 #include "RenderListItem.h"
@@ -68 +71 @@
     
     // Find the top-most blockquote from the start.
-    Node* topBlockquote = highestEnclosingNodeOfType(pos, isMailBlockquote);
+    RefPtr topBlockquote = highestEnclosingNodeOfType(pos, isMailBlockquote);
     if (!topBlockquote || !topBlockquote->parentNode() || !topBlockquote->isElementNode())
         return;
-    
-    auto breakNode = HTMLBRElement::create(document());
-
-    bool isLastVisPosInNode = isLastVisiblePositionInNode(visiblePos, topBlockquote);
+
+    auto breakNode = [&]() -> Ref<HTMLElement> {
+        auto lineBreak = HTMLBRElement::create(document());
+        RefPtr containerNode = pos.containerNode();
+        if (!containerNode || !containerNode->renderStyle())
+            return lineBreak;
+
+        auto* parentStyle = topBlockquote->parentNode()->renderStyle();
+        if (!parentStyle)
+            return lineBreak;
+
+        if (parentStyle->direction() == containerNode->renderStyle()->direction())
+            return lineBreak;
+
+        auto container = HTMLDivElement::create(document());
+        container->setDir(autoAtom());
+        container->appendChild(lineBreak);
+        return container;
+    }();
+
+    bool isLastVisPosInNode = isLastVisiblePositionInNode(visiblePos, topBlockquote.get());
 
     // If the position is at the beginning of the top quoted content, we don't need to break the quote.
     // Instead, insert the break before the blockquote, unless the position is as the end of the quoted content.
-    if (isFirstVisiblePositionInNode(visiblePos, topBlockquote) && !isLastVisPosInNode) {
+    if (isFirstVisiblePositionInNode(visiblePos, topBlockquote.get()) && !isLastVisPosInNode) {
         insertNodeBefore(breakNode.copyRef(), *topBlockquote);
         setEndingSelection(VisibleSelection(positionBeforeNode(breakNode.ptr()), Affinity::Downstream, endingSelection().isDirectional()));