Bug 1627175 - part 44: Add `HTMLEditUtils::IsInvisibleBRElement()` for avoiding a mistake r=m_kato

When I review patches, sometimes I saw wrong usage of `!IsVisibleBRElement()`.
It means that it's an invisible <br> element **or** non-<br> element node,
but developers may think it checks whether it's an invisible `<br>` element
or not without checking the specifying content is a <br> element.

For avoiding this, there should be `IsInvisibleBRElement()` too.

Depends on D114932

Differential Revision: https://phabricator.services.mozilla.com/D114933

editor/libeditor/HTMLEditSubActionHandler.cpp

@@ -2354,8 +2354,7 @@ EditorDOMPoint HTMLEditor::GetGoodCaretPointFor(
   // If we are going backward, put caret to next node unless aContent is an
   // invisible `<br>` element.
   // XXX Shouldn't we put caret to first leaf of the next node?
-  if (!aContent.IsHTMLElement(nsGkAtoms::br) ||
-      HTMLEditUtils::IsVisibleBRElement(aContent)) {
+  if (!HTMLEditUtils::IsInvisibleBRElement(aContent)) {
     EditorDOMPoint ret(EditorDOMPoint::After(aContent));
     NS_WARNING_ASSERTION(ret.IsSet(), "Failed to set after aContent");
     return ret;
@@ -8203,8 +8202,8 @@ nsresult HTMLEditor::AdjustCaretPositionAndEnsurePaddingBRElement(
           previousEditableContent->IsHTMLElement(nsGkAtoms::br)) {
         // If it's an invisible `<br>` element, we need to insert a padding
         // `<br>` element for making empty line have one-line height.
-        if (!HTMLEditUtils::IsVisibleBRElement(*previousEditableContent,
-                                               editingHost)) {
+        if (HTMLEditUtils::IsInvisibleBRElement(*previousEditableContent,
+                                                editingHost)) {
           CreateElementResult createPaddingBRResult =
               InsertPaddingBRElementForEmptyLastLineWithTransaction(point);
           if (createPaddingBRResult.Failed()) {

editor/libeditor/HTMLEditUtils.h

@@ -263,9 +263,9 @@ class HTMLEditUtils final {
                                     dom::Text& aText);
 
   /**
-   * IsVisibleBRElement() returns true if aContent is a visible HTML <br>
-   * element, i.e., not a padding <br> element for making last line in a
-   * block element visible.
+   * IsVisibleBRElement() and IsInvisibleBRElement() return true if aContent is
+   * a visible HTML <br> element, i.e., not a padding <br> element for making
+   * last line in a block element visible, or an invisible <br> element.
    *
    * If aEditingHost is omitted, this computes parent editable block for you.
    * But if you call this a lot, please specify proper editing host (or parent
@@ -273,6 +273,11 @@ class HTMLEditUtils final {
    */
   static bool IsVisibleBRElement(const nsIContent& aContent,
                                  const Element* aEditingHost = nullptr);
+  static bool IsInvisibleBRElement(const nsIContent& aContent,
+                                   const Element* aEditingHost = nullptr) {
+    return aContent.IsHTMLElement(nsGkAtoms::br) &&
+           !HTMLEditUtils::IsVisibleBRElement(aContent, aEditingHost);
+  }
 
   /**
    * IsEmptyNode() returns false if aNode has some visible content nodes,

editor/libeditor/HTMLEditorDataTransfer.cpp

@@ -340,10 +340,8 @@ HTMLEditor::HTMLWithContextInserter::GetInvisibleBRElementAtPoint(
   WSRunScanner wsRunScannerAtInsertionPoint(mHTMLEditor.GetActiveEditingHost(),
                                             aPointToInsert);
   if (wsRunScannerAtInsertionPoint.GetEndReasonContent() &&
-      wsRunScannerAtInsertionPoint.GetEndReasonContent()->IsHTMLElement(
-          nsGkAtoms::br) &&
-      !HTMLEditUtils::IsVisibleBRElement(
-          *wsRunScannerAtInsertionPoint.EndReasonBRElementPtr(),
+      HTMLEditUtils::IsInvisibleBRElement(
+          *wsRunScannerAtInsertionPoint.GetEndReasonContent(),
           wsRunScannerAtInsertionPoint.GetEditingHost())) {
     return wsRunScannerAtInsertionPoint.EndReasonBRElementPtr();
   }
@@ -406,7 +404,7 @@ HTMLEditor::HTMLWithContextInserter::GetNewCaretPointAfterInsertingHTML(
   if (wsRunScannerAtCaret
           .ScanPreviousVisibleNodeOrBlockBoundaryFrom(pointToPutCaret)
           .ReachedBRElement() &&
-      !HTMLEditUtils::IsVisibleBRElement(
+      HTMLEditUtils::IsInvisibleBRElement(
           *wsRunScannerAtCaret.GetStartReasonContent(), editingHost)) {
     WSRunScanner wsRunScannerAtStartReason(
         editingHost,

editor/libeditor/HTMLEditorDeleteHandler.cpp

@@ -1293,7 +1293,7 @@ nsresult HTMLEditor::AutoDeleteRangesHandler::ComputeRangesToDelete(
                 *scanFromCaretPointResult.BRElementPtr(), EditorType::HTML)) {
           return NS_SUCCESS_DOM_NO_OPERATION;
         }
-        if (!HTMLEditUtils::IsVisibleBRElement(
+        if (HTMLEditUtils::IsInvisibleBRElement(
                 *scanFromCaretPointResult.BRElementPtr(), editingHost)) {
           EditorDOMPoint newCaretPosition =
               aDirectionAndAmount == nsIEditor::eNext
@@ -1567,7 +1567,7 @@ EditActionResult HTMLEditor::AutoDeleteRangesHandler::Run(
                 *scanFromCaretPointResult.BRElementPtr(), EditorType::HTML)) {
           return EditActionCanceled();
         }
-        if (!HTMLEditUtils::IsVisibleBRElement(
+        if (HTMLEditUtils::IsInvisibleBRElement(
                 *scanFromCaretPointResult.BRElementPtr(), editingHost)) {
           // TODO: We should extend the range to delete again before/after
           //       the caret point and use `HandleDeleteNonCollapsedRanges()`
@@ -1620,7 +1620,7 @@ EditActionResult HTMLEditor::AutoDeleteRangesHandler::Run(
               return EditActionResult(NS_ERROR_FAILURE);
             }
             if (scanFromCaretPointResult.ReachedBRElement() &&
-                !HTMLEditUtils::IsVisibleBRElement(
+                HTMLEditUtils::IsInvisibleBRElement(
                     *scanFromCaretPointResult.BRElementPtr(), editingHost)) {
               return EditActionHandled(NS_ERROR_EDITOR_UNEXPECTED_DOM_TREE);
             }
@@ -2387,9 +2387,8 @@ EditActionResult HTMLEditor::AutoDeleteRangesHandler::HandleDeleteAtomicContent(
     const EditorDOMPoint& aCaretPoint,
     const WSRunScanner& aWSRunScannerAtCaret) {
   MOZ_ASSERT(aHTMLEditor.IsEditActionDataAvailable());
-  MOZ_ASSERT_IF(aAtomicContent.IsHTMLElement(nsGkAtoms::br),
-                HTMLEditUtils::IsVisibleBRElement(
-                    aAtomicContent, aWSRunScannerAtCaret.GetEditingHost()));
+  MOZ_ASSERT(!HTMLEditUtils::IsInvisibleBRElement(
+      aAtomicContent, aWSRunScannerAtCaret.GetEditingHost()));
   MOZ_ASSERT(&aAtomicContent != aWSRunScannerAtCaret.GetEditingHost());
 
   nsresult rv =
@@ -3373,8 +3372,7 @@ bool HTMLEditor::AutoDeleteRangesHandler::AutoBlockElementsJoiner::
             {EmptyCheckOption::TreatSingleBRElementAsVisible})) {
       continue;
     }
-    if (!content->IsHTMLElement(nsGkAtoms::br) ||
-        HTMLEditUtils::IsVisibleBRElement(*content)) {
+    if (!HTMLEditUtils::IsInvisibleBRElement(*content)) {
       return false;
     }
   }
@@ -4434,8 +4432,7 @@ nsresult HTMLEditor::AutoDeleteRangesHandler::AutoBlockElementsJoiner::
       NS_WARNING_ASSERTION(editingHost, "There was no editing host");
       nsIContent* nextContent =
           atStart.IsEndOfContainer() && range.StartRef().GetChild() &&
-                  range.StartRef().GetChild()->IsHTMLElement(nsGkAtoms::br) &&
-                  !HTMLEditUtils::IsVisibleBRElement(
+                  HTMLEditUtils::IsInvisibleBRElement(
                       *range.StartRef().GetChild(), editingHost)
               ? HTMLEditUtils::GetNextContent(
                     *atStart.ContainerAsContent(),