Use upstream libaddressinput in Chrome.

third_party/libaddressinput/chromium/string_compare.cc

+// Copyright 2014 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 "third_party/libaddressinput/src/cpp/src/util/string_compare.h"
+
+#include "base/basictypes.h"
+#include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "third_party/icu/source/i18n/unicode/coll.h"
+
+namespace i18n {
+namespace addressinput {
+
+class StringCompare::Impl {

[Evan Stade, 2014/06/30 18:49:38]

Why is this class an inner class of StringCompare as opposed to say a
LazyInstance?

You create collator_ lazily but impl_ is not lazy. If you avoid using impl_ and
make a file-level static LazyInstance you can initialize the collator in the
constructor. This also means all StringCompare instances share a single
collator, which saves a little space (if multiple StringCompare objects are even
constructed).

[please use gerrit instead, 2014/07/01 04:53:50]

Done.

+ public:
+  Impl() {}
+
+  ~Impl() {}
+
+  bool NaturalEquals(const std::string& a, const std::string& b) const {
+    return NaturalCompare(a, b) == 0;
+  }
+
+  bool NaturalLess(const std::string& a, const std::string& b) const {
+    return NaturalCompare(a, b) < 0;
+  }
+
+ private:
+  int NaturalCompare(const std::string& a, const std::string& b) const {
+    UErrorCode error_code = U_ZERO_ERROR;
+    if (!collator_) {
+      collator_.reset(
+          icu::Collator::createInstance(icu::Locale::getRoot(), error_code));
+      DCHECK(U_SUCCESS(error_code));
+      collator_->setStrength(icu::Collator::PRIMARY);
+    }
+    error_code = U_ZERO_ERROR;
+    int result = collator_->compareUTF8(a, b, error_code);
+    DCHECK(U_SUCCESS(error_code));
+    return result;
+  }
+
+  // ::scoped_ptr is from "base/memory/scoped_ptr.h", which does not interfere
+  // with ::i18n::addressinput::scoped_ptr from
+  // <libaddressinput/util/scoped_ptr.h>.
+  mutable ::scoped_ptr<icu::Collator> collator_;
+
+  DISALLOW_COPY_AND_ASSIGN(Impl);
+};
+
+StringCompare::StringCompare() : impl_(new Impl) {

[Evan Stade, 2014/06/30 18:49:38]

nit: {} on one line

[please use gerrit instead, 2014/07/01 04:53:50]

Done. (I have to remember to fix this after every clang-format, but sometimes
forget.)

+}
+
+StringCompare::~StringCompare() {

[Evan Stade, 2014/06/30 18:49:38]

nit: {} on one line

[please use gerrit instead, 2014/07/01 04:53:50]

Done.

+}
+
+bool StringCompare::NaturalEquals(const std::string& a,
+                                  const std::string& b) const {
+  return impl_->NaturalEquals(a, b);
+}
+
+bool StringCompare::NaturalLess(const std::string& a,
+                                const std::string& b) const {
+  return impl_->NaturalLess(a, b);
+}
+
+}  // namespace addressinput
+}  // namespace i18n