[LayoutNG] Support objects that are opaque to whitespace collapsing

third_party/WebKit/Source/core/layout/ng/inline/ng_inline_items_builder.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef NGInlineItemsBuilder_h
 #define NGInlineItemsBuilder_h
 
 #include "core/CoreExport.h"
 #include "core/layout/ng/inline/ng_inline_node.h"
 #include "platform/wtf/Allocator.h"
@@ skipping 45 matching lines @@
   // Currently this function is for adding control characters such as
   // objectReplacementCharacter, and does not support all space collapsing logic
   // as its String version does.
   // See the String version for using nullptr for ComputedStyle and
   // LayoutObject.
   void Append(NGInlineItem::NGInlineItemType,
               UChar,
               const ComputedStyle* = nullptr,
               LayoutObject* = nullptr);
 
-  // Append a non-character item.
-  void Append(NGInlineItem::NGInlineItemType,
-              const ComputedStyle* = nullptr,
-              LayoutObject* = nullptr);
+  // Append a character.
+  // The character is opaque to space collapsing; i.e., spaces before this
+  // character and after this character can collapse as if this character does
+  // not exist.
+  void AppendAsOpaqueToSpaceCollapsing(NGInlineItem::NGInlineItemType, UChar);

[eae, 2017/06/23 18:49:09]

These names are a little too verbose, how about shortening it to AppendOpaque?

Thanks for the great comments explaining exactly what these methods do!

+
+  // Append a non-character item that is opaque to space collapsing.
+  void AppendAsOpaqueToSpaceCollapsing(NGInlineItem::NGInlineItemType,
+                                       const ComputedStyle* = nullptr,
+                                       LayoutObject* = nullptr);
 
   // Append a Bidi control character, for LTR or RTL depends on the style.
   void AppendBidiControl(const ComputedStyle*, UChar ltr, UChar rtl);
 
   void EnterBlock(const ComputedStyle*);
   void ExitBlock();
   void EnterInline(LayoutObject*);
   void ExitInline(LayoutObject*);
 
  private:
@@ skipping 25 matching lines @@
                                     LayoutObject*);
 
   void AppendForcedBreak(const ComputedStyle*, LayoutObject*);
 
   // Because newlines may be removed depends on following characters, newlines
   // at the end of input string is not added to |text_| but instead
   // |has_pending_newline_| flag is set.
   // This function determines whether to add the newline or ignore.
   void ProcessPendingNewline(const String&, const ComputedStyle*);
 
-  // Removes the collapsible space at the end of |text_| if exists.
-  void RemoveTrailingCollapsibleSpaceIfExists(unsigned*);
-  void RemoveTrailingCollapsibleSpace(unsigned*);
-
-  void RemoveTrailingCollapsibleNewlineIfNeeded(unsigned*,
-                                                const String&,
+  void RemoveTrailingCollapsibleSpaceIfExists();
+  void RemoveTrailingCollapsibleSpace(unsigned);
+  void RemoveTrailingCollapsibleNewlineIfNeeded(const String&,
                                                 unsigned,
                                                 const ComputedStyle*);
 
   void Enter(LayoutObject*, UChar);
   void Exit(LayoutObject*);
 };
 
 }  // namespace blink
 
 #endif  // NGInlineItemsBuilder_h