Refactoring: Moved the function CompareString16WithCollator from ui/base/l10n to base/i18n. The function LocalAwareCompareFilenames at base/i18n/file_util_icu.cc needed a function to sort string with consideration of a locale, but it couldn't refer ui/base.

BUG=55883 (Indirectly)
TEST=Unit tests

Review URL: https://chromiumcodereview.appspot.com/14044002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@195711 0039d316-1c4b-4281-b951-d872f2087c98

11 files changed, 89 insertions, 90 deletions

diff --git a/base/base.gyp b/base/base.gyp
index b026dcb..a0da4a8 100644
--- a/base/base.gyp
+++ b/base/base.gyp
@@ -322,6 +322,8 @@
         'i18n/number_formatting.h',
         'i18n/rtl.cc',
         'i18n/rtl.h',
+        'i18n/string_compare.cc',
+        'i18n/string_compare.h',
         'i18n/string_search.cc',
         'i18n/string_search.h',
         'i18n/time_formatting.cc',
diff --git a/base/i18n/file_util_icu.cc b/base/i18n/file_util_icu.cc
index f023a4f..a29eb4b 100644
--- a/base/i18n/file_util_icu.cc
+++ b/base/i18n/file_util_icu.cc
@@ -8,6 +8,7 @@
 
 #include "base/files/file_path.h"
 #include "base/i18n/icu_string_conversions.h"
+#include "base/i18n/string_compare.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
@@ -79,56 +80,6 @@ IllegalCharacters::IllegalCharacters() {
   set->freeze();
 }
 
-class LocaleAwareComparator {
- public:
-  static LocaleAwareComparator* GetInstance() {
-    return Singleton<LocaleAwareComparator,
-                     LeakySingletonTraits<LocaleAwareComparator> >::get();
-  }
-
-  // Note: A similar function is available in l10n_util.
-  // We cannot use it because base should not depend on l10n_util.
-  // TODO(yuzo): Move some of l10n_util to base.
-  int Compare(const string16& a, const string16& b) {
-    // We are not sure if Collator::compare is thread-safe.
-    // Use an AutoLock just in case.
-    base::AutoLock auto_lock(lock_);
-
-    UErrorCode error_code = U_ZERO_ERROR;
-    UCollationResult result = collator_->compare(
-        static_cast<const UChar*>(a.c_str()),
-        static_cast<int>(a.length()),
-        static_cast<const UChar*>(b.c_str()),
-        static_cast<int>(b.length()),
-        error_code);
-    DCHECK(U_SUCCESS(error_code));
-    return result;
-  }
-
- private:
-  friend struct DefaultSingletonTraits<LocaleAwareComparator>;
-
-  LocaleAwareComparator() {
-    UErrorCode error_code = U_ZERO_ERROR;
-    // Use the default collator. The default locale should have been properly
-    // set by the time this constructor is called.
-    collator_.reset(icu::Collator::createInstance(error_code));
-    DCHECK(U_SUCCESS(error_code));
-    // Make it case-sensitive.
-    collator_->setStrength(icu::Collator::TERTIARY);
-    // Note: We do not set UCOL_NORMALIZATION_MODE attribute. In other words, we
-    // do not pay performance penalty to guarantee sort order correctness for
-    // non-FCD (http://unicode.org/notes/tn5/#FCD) file names. This should be a
-    // reasonable tradeoff because such file names should be rare and the sort
-    // order doesn't change much anyway.
-  }
-
-  scoped_ptr<icu::Collator> collator_;
-  base::Lock lock_;
-
-  DISALLOW_COPY_AND_ASSIGN(LocaleAwareComparator);
-};
-
 }  // namespace
 
 namespace file_util {
@@ -182,20 +133,24 @@ void ReplaceIllegalCharactersInPath(base::FilePath::StringType* file_name,
 
 bool LocaleAwareCompareFilenames(const base::FilePath& a,
                                  const base::FilePath& b) {
+  UErrorCode error_code = U_ZERO_ERROR;
+  // Use the default collator. The default locale should have been properly
+  // set by the time this constructor is called.
+  scoped_ptr<icu::Collator> collator(icu::Collator::createInstance(error_code));
+  DCHECK(U_SUCCESS(error_code));
+  // Make it case-sensitive.
+  collator->setStrength(icu::Collator::TERTIARY);
+
 #if defined(OS_WIN)
-  return LocaleAwareComparator::GetInstance()->Compare(a.value().c_str(),
-                                                       b.value().c_str()) < 0;
+  return base::i18n::CompareString16WithCollator(collator.get(),
+      WideToUTF16(a.value()), WideToUTF16(b.value())) == UCOL_LESS;
 
 #elif defined(OS_POSIX)
   // On linux, the file system encoding is not defined. We assume
   // SysNativeMBToWide takes care of it.
-  //
-  // ICU's collator can take strings in OS native encoding. But we convert the
-  // strings to UTF-16 ourselves to ensure conversion consistency.
-  // TODO(yuzo): Perhaps we should define SysNativeMBToUTF16?
-  return LocaleAwareComparator::GetInstance()->Compare(
+  return base::i18n::CompareString16WithCollator(collator.get(),
       WideToUTF16(base::SysNativeMBToWide(a.value().c_str())),
-      WideToUTF16(base::SysNativeMBToWide(b.value().c_str()))) < 0;
+      WideToUTF16(base::SysNativeMBToWide(b.value().c_str()))) == UCOL_LESS;
 #else
   #error Not implemented on your system
 #endif
diff --git a/base/i18n/string_compare.cc b/base/i18n/string_compare.cc
new file mode 100644
index 0000000..41d19d8
--- /dev/null
+++ b/base/i18n/string_compare.cc
@@ -0,0 +1,29 @@
+// Copyright (c) 2013 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/string_compare.h"
+
+#include "base/logging.h"
+#include "base/utf_string_conversions.h"
+
+namespace base {
+namespace i18n {
+
+// Compares the character data stored in two different string16 strings by
+// specified Collator instance.
+UCollationResult CompareString16WithCollator(const icu::Collator* collator,
+                                             const string16& lhs,
+                                             const string16& rhs) {
+  DCHECK(collator);
+  UErrorCode error = U_ZERO_ERROR;
+  UCollationResult result = collator->compare(
+      static_cast<const UChar*>(lhs.c_str()), static_cast<int>(lhs.length()),
+      static_cast<const UChar*>(rhs.c_str()), static_cast<int>(rhs.length()),
+      error);
+  DCHECK(U_SUCCESS(error));
+  return result;
+}
+
+}  // namespace i18n
+}  // namespace base
diff --git a/base/i18n/string_compare.h b/base/i18n/string_compare.h
new file mode 100644
index 0000000..3c3d010
--- /dev/null
+++ b/base/i18n/string_compare.h
@@ -0,0 +1,28 @@
+// Copyright (c) 2013 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 BASE_I18N_STRING_COMPARE_H_
+#define BASE_I18N_STRING_COMPARE_H_
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include "base/i18n/base_i18n_export.h"
+#include "base/string16.h"
+#include "third_party/icu/public/i18n/unicode/coll.h"
+
+namespace base {
+namespace i18n {
+
+// Compares the two strings using the specified collator.
+BASE_I18N_EXPORT UCollationResult CompareString16WithCollator(
+    const icu::Collator* collator,
+    const string16& lhs,
+    const string16& rhs);
+
+}  // namespace i18n
+}  // namespace base
+
+#endif  // BASE_I18N_STRING_COMPARATOR_H_
diff --git a/chrome/browser/bookmarks/bookmark_model.cc b/chrome/browser/bookmarks/bookmark_model.cc
index d23f645..1985c64 100644
--- a/chrome/browser/bookmarks/bookmark_model.cc
+++ b/chrome/browser/bookmarks/bookmark_model.cc
@@ -9,9 +9,11 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
+#include "base/i18n/string_compare.h"
 #include "base/json/json_string_value_serializer.h"
 #include "base/sequenced_task_runner.h"
 #include "base/string_util.h"
+#include "base/utf_string_conversions.h"
 #include "base/values.h"
 #include "build/build_config.h"
 #include "chrome/browser/bookmarks/bookmark_expanded_state_tracker.h"
@@ -30,7 +32,6 @@
 #include "content/public/browser/notification_source.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
-#include "ui/base/l10n/l10n_util_collator.h"
 #include "ui/gfx/favicon_size.h"
 #include "ui/gfx/image/image_util.h"
 
@@ -166,7 +167,7 @@ class SortComparator : public std::binary_function<const BookmarkNode*,
       // Types are the same, compare the names.
       if (!collator_)
         return n1->GetTitle() < n2->GetTitle();
-      return l10n_util::CompareString16WithCollator(
+      return base::i18n::CompareString16WithCollator(
           collator_, n1->GetTitle(), n2->GetTitle()) == UCOL_LESS;
     }
     // Types differ, sort such that folders come first.
diff --git a/chrome/browser/chromeos/cros/cert_library.cc b/chrome/browser/chromeos/cros/cert_library.cc
index e2309f0..ab5b491 100644
--- a/chrome/browser/chromeos/cros/cert_library.cc
+++ b/chrome/browser/chromeos/cros/cert_library.cc
@@ -8,6 +8,7 @@
 
 #include "base/chromeos/chromeos_version.h"
 #include "base/command_line.h"
+#include "base/i18n/string_compare.h"
 #include "base/memory/weak_ptr.h"
 #include "base/observer_list_threadsafe.h"
 #include "base/string_util.h"
@@ -343,7 +344,7 @@ class CertLibraryImpl
       string16 rhs_name = GetDisplayString(rhs.get(), false);
       if (collator_ == NULL)
         return lhs_name < rhs_name;
-      return l10n_util::CompareString16WithCollator(
+      return base::i18n::CompareString16WithCollator(
           collator_, lhs_name, rhs_name) == UCOL_LESS;
     }
    private:
diff --git a/chrome/browser/ui/autofill/country_combobox_model.cc b/chrome/browser/ui/autofill/country_combobox_model.cc
index fafa49c..4829efa 100644
--- a/chrome/browser/ui/autofill/country_combobox_model.cc
+++ b/chrome/browser/ui/autofill/country_combobox_model.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/ui/autofill/country_combobox_model.h"
 
+#include "base/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "components/autofill/browser/autofill_country.h"
 #include "ui/base/l10n/l10n_util_collator.h"
diff --git a/chrome/browser/ui/webui/options/certificate_manager_handler.cc b/chrome/browser/ui/webui/options/certificate_manager_handler.cc
index f30eaec..1923b04 100644
--- a/chrome/browser/ui/webui/options/certificate_manager_handler.cc
+++ b/chrome/browser/ui/webui/options/certificate_manager_handler.cc
@@ -10,10 +10,12 @@
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/file_util.h"  // for FileAccessProvider
+#include "base/i18n/string_compare.h"
 #include "base/id_map.h"
 #include "base/memory/scoped_vector.h"
 #include "base/safe_strerror_posix.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/certificate_viewer.h"
@@ -28,7 +30,6 @@
 #include "net/base/net_errors.h"
 #include "net/cert/x509_certificate.h"
 #include "ui/base/l10n/l10n_util.h"
-#include "ui/base/l10n/l10n_util_collator.h"
 
 #if defined(OS_CHROMEOS)
 #include "chromeos/dbus/cryptohome_client.h"
@@ -87,7 +88,7 @@ struct DictionaryIdComparator {
     b_dict->GetString(kNameId, &b_str);
     if (collator_ == NULL)
       return a_str < b_str;
-    return l10n_util::CompareString16WithCollator(
+    return base::i18n::CompareString16WithCollator(
         collator_, a_str, b_str) == UCOL_LESS;
   }
 
diff --git a/ui/base/l10n/l10n_util.cc b/ui/base/l10n/l10n_util.cc
index 0b7b9b7..03abc81 100644
--- a/ui/base/l10n/l10n_util.cc
+++ b/ui/base/l10n/l10n_util.cc
@@ -14,6 +14,7 @@
 #include "base/file_util.h"
 #include "base/i18n/file_util_icu.h"
 #include "base/i18n/rtl.h"
+#include "base/i18n/string_compare.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/path_service.h"
 #include "base/string_number_conversions.h"
@@ -777,21 +778,6 @@ string16 GetStringFUTF16Int(int message_id, int64 a) {
   return GetStringFUTF16(message_id, UTF8ToUTF16(base::Int64ToString(a)));
 }
 
-// Compares the character data stored in two different string16 strings by
-// specified Collator instance.
-UCollationResult CompareString16WithCollator(const icu::Collator* collator,
-                                             const string16& lhs,
-                                             const string16& rhs) {
-  DCHECK(collator);
-  UErrorCode error = U_ZERO_ERROR;
-  UCollationResult result = collator->compare(
-      static_cast<const UChar*>(lhs.c_str()), static_cast<int>(lhs.length()),
-      static_cast<const UChar*>(rhs.c_str()), static_cast<int>(rhs.length()),
-      error);
-  DCHECK(U_SUCCESS(error));
-  return result;
-}
-
 // Specialization of operator() method for string16 version.
 template <>
 bool StringComparator<string16>::operator()(const string16& lhs,
@@ -800,7 +786,8 @@ bool StringComparator<string16>::operator()(const string16& lhs,
   // string compare.
   if (!collator_)
     return lhs < rhs;
-  return CompareString16WithCollator(collator_, lhs, rhs) == UCOL_LESS;
+  return base::i18n::CompareString16WithCollator(collator_, lhs, rhs) ==
+      UCOL_LESS;
 };
 
 void SortStrings16(const std::string& locale,
diff --git a/ui/base/l10n/l10n_util_collator.h b/ui/base/l10n/l10n_util_collator.h
index fb43692..44e4a77 100644
--- a/ui/base/l10n/l10n_util_collator.h
+++ b/ui/base/l10n/l10n_util_collator.h
@@ -10,19 +10,13 @@
 #include <string>
 #include <vector>
 
+#include "base/i18n/string_compare.h"
 #include "base/memory/scoped_ptr.h"
-#include "base/utf_string_conversions.h"
 #include "third_party/icu/public/i18n/unicode/coll.h"
 #include "ui/base/ui_export.h"
 
 namespace l10n_util {
 
-// Compares the two strings using the specified collator.
-UI_EXPORT UCollationResult CompareString16WithCollator(
-    const icu::Collator* collator,
-    const string16& lhs,
-    const string16& rhs);
-
 // Used by SortStringsUsingMethod. Invokes a method on the objects passed to
 // operator (), comparing the string results using a collator.
 template <class T, class Method>
@@ -37,8 +31,8 @@ class StringMethodComparatorWithCollator
 
   // Returns true if lhs preceeds rhs.
   bool operator() (T* lhs_t, T* rhs_t) {
-    return CompareString16WithCollator(collator_, (lhs_t->*method_)(),
-                                       (rhs_t->*method_)()) == UCOL_LESS;
+    return base::i18n::CompareString16WithCollator(collator_,
+        (lhs_t->*method_)(), (rhs_t->*method_)()) == UCOL_LESS;
   }
 
  private:
diff --git a/ui/base/models/table_model.cc b/ui/base/models/table_model.cc
index f59e7dd..47520f0 100644
--- a/ui/base/models/table_model.cc
+++ b/ui/base/models/table_model.cc
@@ -4,9 +4,9 @@
 
 #include "ui/base/models/table_model.h"
 
+#include "base/i18n/string_compare.h"
 #include "base/logging.h"
 #include "ui/base/l10n/l10n_util.h"
-#include "ui/base/l10n/l10n_util_collator.h"
 #include "ui/gfx/image/image_skia.h"
 
 namespace ui {
@@ -76,7 +76,7 @@ int TableModel::CompareValues(int row1, int row2, int column_id) {
   icu::Collator* collator = GetCollator();
 
   if (collator)
-    return l10n_util::CompareString16WithCollator(collator, value1, value2);
+    return base::i18n::CompareString16WithCollator(collator, value1, value2);
 
   NOTREACHED();
   return 0;