Avoid sync IPCs for firstRectForCharacterRange/attributedSubstringForProposedRange.

content/browser/renderer_host/render_widget_host_view_mac.mm

 // Copyright (c) 2012 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.
 
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
 
 #import <objc/runtime.h>
 #include <OpenGL/gl.h>
 #include <QuartzCore/QuartzCore.h>
 
@@ skipping 1175 matching lines @@
 
 void RenderWidgetHostViewMac::StopSpeaking() {
   if ([NSApp respondsToSelector:@selector(stopSpeaking:)])
     [NSApp stopSpeaking:cocoa_view_];
 }
 
 //
 // RenderWidgetHostViewCocoa uses the stored selection text,
 // which implements NSServicesRequests protocol.
 //
 void RenderWidgetHostViewMac::SelectionChanged(const base::string16& text,

[yukawa, 2015/08/20 09:14:49]

Just out of curiosity, if we send NSAttributedString rather than base::string16
from the rendered to the browser process, is it possible to return the string
with the format information in attributedSubstringForProposedRange?

[Shu Chen, 2015/08/21 03:13:11]

It is not easy to do that without a bigger refactoring.
SelectionChanged() is for all platforms but Attributed-String is only for Mac
platform.

If we want to do that, it should be a separated cl.

                                                size_t offset,
                                                const gfx::Range& range) {
   if (range.is_empty() || text.empty()) {
     selected_text_.clear();
   } else {
     size_t pos = range.GetMin() - offset;
     size_t n = range.length();
 
     DCHECK(pos + n <= text.length()) << "The text can not fully cover range.";
     if (pos >= text.length()) {
@@ skipping 11 matching lines @@
     [cocoa_view_ setMarkedRange:range.ToNSRange()];
   }
 
   RenderWidgetHostViewBase::SelectionChanged(text, offset, range);
 }
 
 void RenderWidgetHostViewMac::SelectionBoundsChanged(
     const ViewHostMsg_SelectionBounds_Params& params) {
   if (params.anchor_rect == params.focus_rect)
     caret_rect_ = params.anchor_rect;
+  first_selection_rect_ = params.anchor_rect;
 }
 
 void RenderWidgetHostViewMac::SetShowingContextMenu(bool showing) {
   RenderWidgetHostViewBase::SetShowingContextMenu(showing);
 
   // Create a fake mouse event to inform the render widget that the mouse
   // left or entered.
   NSWindow* window = [cocoa_view_ window];
   // TODO(asvitkine): If the location outside of the event stream doesn't
   // correspond to the current event (due to delayed event processing), then
@@ skipping 208 matching lines @@
                "RenderWidgetHostViewMac::GetFirstRectForCharacterRange");
 
   // If requested range is same as caret location, we can just return it.
   if (selection_range_.is_empty() && gfx::Range(range) == selection_range_) {
     if (actual_range)
       *actual_range = range;
     *rect = NSRectFromCGRect(caret_rect_.ToCGRect());
     return true;
   }
 
+  if (composition_range_.is_empty()) {
+    *actual_range = selection_range_.ToNSRange();
+    *rect = NSRectFromCGRect(first_selection_rect_.ToCGRect());
+    return true;
+  }
+
   const gfx::Range request_range_in_composition =
       ConvertCharacterRangeToCompositionRange(gfx::Range(range));
   if (request_range_in_composition == gfx::Range::InvalidRange())
     return false;
 
   // If firstRectForCharacterRange in WebFrame is failed in renderer,
   // ImeCompositionRangeChanged will be sent with empty vector.
   if (composition_bounds_.empty())
     return false;
   DCHECK_EQ(composition_bounds_.size(), composition_range_.length());
@@ skipping 1414 matching lines @@
   // there. (When this method returns an empty range, the input method doesn't
   // call the setMarkedText method.)
   return hasMarkedText_ ? markedRange_ : NSMakeRange(NSNotFound, 0);
 }
 
 - (NSAttributedString*)attributedSubstringForProposedRange:(NSRange)range
     actualRange:(NSRangePointer)actualRange {
   // TODO(thakis): Pipe |actualRange| through TextInputClientMac machinery.
   if (actualRange)
     *actualRange = range;
-  NSAttributedString* str =
-      TextInputClientMac::GetInstance()->GetAttributedSubstringFromRange(
-          renderWidgetHostView_->render_widget_host_, range);
-  return str;
+  gfx::Range expected_range;
+  std::wstring expected_text;  // Using wide string for string truncation.
+  std::string result_text("");
+
+  if (!renderWidgetHostView_->composition_range().is_empty()) {
+    expected_range = renderWidgetHostView_->composition_range();
+    expected_text = base::UTF16ToWide(markedText_);
+  } else if (!renderWidgetHostView_->selection_range().is_empty()) {

[yukawa, 2015/08/20 09:14:49]

I think we can take advantage of |RenderWidgetHostViewBase::selection_text_| and
|RenderWidgetHostViewBase::selection_text_offset_| here.  In order to support
IMR_RECONVERTSTRING on Windows, |RenderWidgetHostViewBase::selection_text_|
generally contains preceding and trailing characters around the actual text
selection, which means that we can support a bit wider range than the selected
range.

[Shu Chen, 2015/08/21 03:13:11]

Done.

+    expected_range = renderWidgetHostView_->selection_range();
+    expected_text = base::UTF8ToWide(renderWidgetHostView_->selected_text());
+  }
+
+  if (expected_range.start() <= range.location &&

[yukawa, 2015/08/20 09:14:49]

Don't we need to return nil when there is no intersection between
|expected_range| and |range|?

Also don't we need to update |range| (or |actualRange|) with |expected_range|?

https://developer.apple.com/library/mac/documentation/Cocoa/Reference/NSTextI...:

[Shu Chen, 2015/08/21 03:13:11]

Done. I think we don't need to update |actualRange| because we always return the
text according to |range|.

+      expected_range.end() >= range.location + range.length) {
+    result_text = base::WideToUTF8(expected_text.substr(
+        range.location - expected_range.start(), range.length));
+  }
+
+  NSString *nstr = [[NSString alloc] initWithUTF8String:result_text.c_str()];
+  return [[NSAttributedString alloc] initWithString:nstr];
 }
 
 - (NSInteger)conversationIdentifier {
   return reinterpret_cast<NSInteger>(self);
 }
 
 // Each RenderWidgetHostViewCocoa has its own input context, but we return
 // nil when the caret is in non-editable content or password box to avoid
 // making input methods do their work.
 - (NSTextInputContext *)inputContext {
@@ skipping 411 matching lines @@
 
 // "-webkit-app-region: drag | no-drag" is implemented on Mac by excluding
 // regions that are not draggable. (See ControlRegionView in
 // native_app_window_cocoa.mm). This requires the render host view to be
 // draggable by default.
 - (BOOL)mouseDownCanMoveWindow {
   return YES;
 }
 
 @end