Fix RenderTextWin base dir and adjacent char code; remove test exceptions; etc.

ui/gfx/render_text_win.cc

Index: ui/gfx/render_text_win.cc
diff --git a/ui/gfx/render_text_win.cc b/ui/gfx/render_text_win.cc
index c2a2c2c047b3422daf88eeacc1b6d62bb136c64a..7d63e4fc1401c0c83dbc7a6bf1f6ba6829feddb2 100644
--- a/ui/gfx/render_text_win.cc
+++ b/ui/gfx/render_text_win.cc
@@ -7,6 +7,7 @@
 #include <algorithm>
 
 #include "base/i18n/break_iterator.h"
+#include "base/i18n/rtl.h"
 #include "base/logging.h"
 #include "base/string_split.h"
 #include "base/string_util.h"
@@ -302,11 +303,9 @@ RenderTextWin::~RenderTextWin() {
 }
 
 base::i18n::TextDirection RenderTextWin::GetTextDirection() {
-  // TODO(benrg): Code moved from RenderText::GetTextDirection. Needs to be
-  // replaced by a correct Windows implementation.
-  if (base::i18n::IsRTL())
-    return base::i18n::RIGHT_TO_LEFT;
-  return base::i18n::LEFT_TO_RIGHT;
+  EnsureLayout();
+  return (script_state_.uBidiLevel == 0) ?
+      base::i18n::LEFT_TO_RIGHT : base::i18n::RIGHT_TO_LEFT;
 }
 
 Size RenderTextWin::GetStringSize() {
@@ -365,12 +364,13 @@ SelectionModel RenderTextWin::AdjacentCharSelectionModel(
   DCHECK(!needs_layout_);
   internal::TextRun* run;
   size_t run_index = GetRunContainingCaret(selection);
-  if (run_index == runs_.size()) {
+  if (run_index >= runs_.size()) {
     // The cursor is not in any run: we're at the visual and logical edge.
     SelectionModel edge = EdgeSelectionModel(direction);
     if (edge.caret_pos() == selection.caret_pos())
       return edge;
-    run = direction == CURSOR_RIGHT ? runs_.front() : runs_.back();
+    int visual_index = (direction == CURSOR_RIGHT) ? 0 : runs_.size() - 1;
+    run = runs_[visual_to_logical_[visual_index]];
   } else {
     // If the cursor is moving within the current run, just move it by one
     // grapheme in the appropriate direction.
@@ -596,12 +596,19 @@ void RenderTextWin::ItemizeLogicalText() {
   runs_.reset();
   string_size_ = Size(0, GetFont().GetHeight());
   common_baseline_ = 0;
+  script_state_.uBidiLevel = 0;

[Alexei Svitkine (slow), 2012/07/03 18:37:57]

Can you add a case to your test that would fail if this line was removed? (i.e.
check empty string is LTR, then set to RTL and check is RTL, then set back to
empty string and check its back to LTR).

[msw, 2012/07/03 22:34:04]

I adjusted the logic and added a test.

   if (text().empty())
     return;
 
   const wchar_t* raw_text = text().c_str();
   const int text_length = text().length();
 
+  // Initialize the base direction of the text.
+  if (base::i18n::GetFirstStrongCharacterDirection(text()) ==
+      base::i18n::RIGHT_TO_LEFT) {

[Alexei Svitkine (slow), 2012/07/03 18:37:57]

Nit: Indent 4 more spaces since it's breaking on a ==.

[msw, 2012/07/03 22:34:04]

Moot.

+    script_state_.uBidiLevel = 1;
+  }
+
   HRESULT hr = E_OUTOFMEMORY;
   int script_items_count = 0;
   std::vector<SCRIPT_ITEM> script_items;