Introduce InlineTextBoxesOf() for ease of loop over InlineTextBox of LayoutText

third_party/WebKit/Source/core/editing/VisibleUnits.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights
  * reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 815 matching lines @@
        next = next->NextInPreOrder(container)) {
     if (next->IsLayoutBlock())
       return 0;
     if (next->IsBR())
       return 0;
     if (IsNonTextLeafChild(next))
       return 0;
     if (next->IsText()) {
       InlineTextBox* match = 0;
       int min_offset = INT_MAX;
-      for (InlineTextBox* box = ToLayoutText(next)->FirstTextBox(); box;
-           box = box->NextTextBox()) {
+      for (InlineTextBox* box : InlineTextBoxesOf(*ToLayoutText(next))) {
         int caret_min_offset = box->CaretMinOffset();
         if (caret_min_offset < min_offset) {
           match = box;
           min_offset = caret_min_offset;
         }
       }
       if (match)
         return match;
     }
   }
@@ skipping 74 matching lines @@
     }
     if (layout_object->IsBox()) {
       inline_box = ToLayoutBox(layout_object)->InlineBoxWrapper();
       if (!inline_box || (caret_offset > inline_box->CaretMinOffset() &&
                           caret_offset < inline_box->CaretMaxOffset()))
         return InlineBoxPosition(inline_box, caret_offset);
     }
   } else {
     LayoutText* text_layout_object = ToLayoutText(layout_object);
 
-    InlineTextBox* box;
-    InlineTextBox* candidate = 0;
+    InlineTextBox* candidate = nullptr;
 
-    for (box = text_layout_object->FirstTextBox(); box;
-         box = box->NextTextBox()) {
+    for (InlineTextBox* box : InlineTextBoxesOf(*text_layout_object)) {
       int caret_min_offset = box->CaretMinOffset();
       int caret_max_offset = box->CaretMaxOffset();
 
       if (caret_offset < caret_min_offset || caret_offset > caret_max_offset ||
           (caret_offset == caret_max_offset && box->IsLineBreak()))
         continue;
 
       if (caret_offset > caret_min_offset && caret_offset < caret_max_offset)
         return InlineBoxPosition(box, caret_offset);
 
       if (((caret_offset == caret_max_offset) ^
            (affinity == TextAffinity::kDownstream)) ||
           ((caret_offset == caret_min_offset) ^
            (affinity == TextAffinity::kUpstream)) ||
           (caret_offset == caret_max_offset && box->NextLeafChild() &&
-           box->NextLeafChild()->IsLineBreak()))
+           box->NextLeafChild()->IsLineBreak())) {
+        inline_box = box;
         break;
+      }
 
       candidate = box;
     }
     if (candidate && candidate == text_layout_object->LastTextBox() &&
         affinity == TextAffinity::kDownstream) {
-      box = SearchAheadForBetterMatch(text_layout_object);
-      if (box)
-        caret_offset = box->CaretMinOffset();
+      inline_box = SearchAheadForBetterMatch(text_layout_object);
+      if (inline_box)
+        caret_offset = inline_box->CaretMinOffset();
     }
-    inline_box = box ? box : candidate;
+    if (!inline_box)
+      inline_box = candidate;
   }
 
   if (!inline_box)
     return InlineBoxPosition(inline_box, caret_offset);
 
   unsigned char level = inline_box->BidiLevel();
 
   if (inline_box->Direction() == primary_direction) {
     if (caret_offset == inline_box->CaretRightmostOffset()) {
       InlineBox* next_box = inline_box->NextLeafChild();
@@ skipping 333 matching lines @@
 
   const int offset_in_node = position.ComputeEditingOffset();
   LayoutObject* layout_object =
       AssociatedLayoutObjectOf(*anchor_node, offset_in_node);
   if (!layout_object)
     return false;
 
   LayoutText* text_layout_object = ToLayoutText(layout_object);
   const int text_offset =
       offset_in_node - text_layout_object->TextStartOffset();
-  for (InlineTextBox* box = text_layout_object->FirstTextBox(); box;
-       box = box->NextTextBox()) {
+  for (InlineTextBox* box : InlineTextBoxesOf(*text_layout_object)) {
     if (text_offset < static_cast<int>(box->Start()) &&
         !text_layout_object->ContainsReversedText()) {
       // The offset we're looking for is before this node
       // this means the offset must be in content that is
       // not laid out. Return false.
       return false;
     }
     if (box->ContainsCaretOffset(text_offset)) {
       // Return false for offsets inside composed characters.
       return text_offset == text_layout_object->CaretMinOffset() ||
@@ skipping 232 matching lines @@
 // TODO(editing-dev): This function is just moved out from
 // |MostBackwardCaretPosition()|. We should study this function more and
 // name it appropriately. See https://trac.webkit.org/changeset/32438/
 // which introduce this.
 static bool CanBeBackwardCaretPosition(const LayoutText* text_layout_object,
                                        int offset_in_node) {
   const unsigned text_start_offset = text_layout_object->TextStartOffset();
   DCHECK_GE(offset_in_node, static_cast<int>(text_start_offset));
   const unsigned text_offset = offset_in_node - text_start_offset;
   InlineTextBox* const last_text_box = text_layout_object->LastTextBox();
-  for (InlineTextBox* box = text_layout_object->FirstTextBox(); box;
-       box = box->NextTextBox()) {
+  for (InlineTextBox* box : InlineTextBoxesOf(*text_layout_object)) {
     if (text_offset == box->Start()) {
       if (text_layout_object->IsTextFragment() &&
           ToLayoutTextFragment(text_layout_object)
               ->IsRemainingTextLayoutObject()) {
         // |offset_in_node| is at start of remaining text of
         // |Text| node with :first-letter.
         DCHECK_GE(offset_in_node, 1);
         LayoutObject* first_letter_layout_object =
             ToLayoutTextFragment(text_layout_object)
                 ->GetFirstLetterPseudoElement()
@@ skipping 134 matching lines @@
 // TODO(editing-dev): This function is just moved out from
 // |MostForwardCaretPosition()|. We should study this function more and
 // name it appropriately. See https://trac.webkit.org/changeset/32438/
 // which introduce this.
 static bool CanBeForwardCaretPosition(const LayoutText* text_layout_object,
                                       int offset_in_node) {
   const unsigned text_start_offset = text_layout_object->TextStartOffset();
   DCHECK_GE(offset_in_node, static_cast<int>(text_start_offset));
   const unsigned text_offset = offset_in_node - text_start_offset;
   InlineTextBox* const last_text_box = text_layout_object->LastTextBox();
-  for (InlineTextBox* box = text_layout_object->FirstTextBox(); box;
-       box = box->NextTextBox()) {
+  for (InlineTextBox* box : InlineTextBoxesOf(*text_layout_object)) {
     if (text_offset <= box->end()) {
       if (text_offset >= box->Start())
         return true;
       continue;
     }
 
     if (box == last_text_box || text_offset != box->Start() + box->Len())
       continue;
 
     if (DoesContinueOnNextLine(*text_layout_object, box, text_offset))
@@ skipping 881 matching lines @@
 
 IntRect ComputeTextRect(const EphemeralRangeInFlatTree& range) {
   return EnclosingIntRect(ComputeTextRectTemplate(range));
 }
 
 FloatRect ComputeTextFloatRect(const EphemeralRange& range) {
   return ComputeTextRectTemplate(range);
 }
 
 }  // namespace blink