[rendertext,i18n] Added flag to force RTL rendering

base/i18n/rtl.cc

 // Copyright (c) 2011 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 "base/i18n/rtl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 33 matching lines @@
     result += '-';
     result += country;
   }
 
   if (variant != NULL && *variant != '\0')
     result += '@' + base::ToLowerASCII(variant);
 
   return result;
 }
 
+bool HasForcedTextDirectionSwitch() {

[msw, 2017/05/01 20:56:18]

nit: "// Get the cached switch presence; avoids repeated lookup in the common
case." (or you can inline this static bool in the function below)

[Kevin Bailey, 2017/05/01 21:21:42]

Done. Seemed like a bit much overhead for a whole function.

+  static bool value = base::CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kForceTextDirection);
+  return value;
+}
+
 // Returns LEFT_TO_RIGHT or RIGHT_TO_LEFT if |character| has strong
 // directionality, returns UNKNOWN_DIRECTION if it doesn't. Please refer to
 // http://unicode.org/reports/tr9/ for more information.
 base::i18n::TextDirection GetCharacterDirection(UChar32 character) {
+  if (HasForcedTextDirectionSwitch()) {
+    base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+    std::string force_flag =
+        command_line->GetSwitchValueASCII(switches::kForceTextDirection);
+
+    if (force_flag == switches::kForceDirectionRTL)
+      return base::i18n::RIGHT_TO_LEFT;
+    if (force_flag == switches::kForceDirectionLTR)
+      return base::i18n::LEFT_TO_RIGHT;
+  }
   // Now that we have the character, we use ICU in order to query for the
   // appropriate Unicode BiDi character type.
   int32_t property = u_getIntPropertyValue(character, UCHAR_BIDI_CLASS);
   if ((property == U_RIGHT_TO_LEFT) ||
       (property == U_RIGHT_TO_LEFT_ARABIC) ||
       (property == U_RIGHT_TO_LEFT_EMBEDDING) ||
       (property == U_RIGHT_TO_LEFT_OVERRIDE)) {
     return base::i18n::RIGHT_TO_LEFT;
   } else if ((property == U_LEFT_TO_RIGHT) ||
              (property == U_LEFT_TO_RIGHT_EMBEDDING) ||
@@ skipping 10 matching lines @@
 #if defined(OS_IOS)
   if (base::ios::IsInForcedRTL())
     return base::i18n::RIGHT_TO_LEFT;
 #endif
 
   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
   if (command_line->HasSwitch(switches::kForceUIDirection)) {
     std::string force_flag =
         command_line->GetSwitchValueASCII(switches::kForceUIDirection);
 
-    if (force_flag == switches::kForceUIDirectionLTR)
+    if (force_flag == switches::kForceDirectionLTR)
       return base::i18n::LEFT_TO_RIGHT;
 
-    if (force_flag == switches::kForceUIDirectionRTL)
+    if (force_flag == switches::kForceDirectionRTL)
       return base::i18n::RIGHT_TO_LEFT;
   }
 
   return base::i18n::UNKNOWN_DIRECTION;
 }
 
 }  // namespace
 
 namespace base {
 namespace i18n {
@@ skipping 342 matching lines @@
       begin == kRightToLeftOverride)
     ++begin_index;
   size_t end_index = text.length() - 1;
   if (text[end_index] == kPopDirectionalFormatting)
     --end_index;
   return text.substr(begin_index, end_index - begin_index + 1);
 }
 
 }  // namespace i18n
 }  // namespace base