Add support for localized time strings with two units, eg. "2 hours 17 minutes"

ui/base/l10n/formatter.h

Index: ui/base/l10n/formatter.h
diff --git a/ui/base/l10n/formatter.h b/ui/base/l10n/formatter.h
new file mode 100644
index 0000000000000000000000000000000000000000..13d2d1a55f0fae00518a160a813a23f74c8f3d1d
--- /dev/null
+++ b/ui/base/l10n/formatter.h
@@ -0,0 +1,118 @@
+// 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.
+
+// This file contains implementation details, the public interface is declared
+// in time_format.h.
+
+#ifndef UI_BASE_L10N_FORMATTER_H_
+#define UI_BASE_L10N_FORMATTER_H_
+
+#include "base/basictypes.h"
+#include "base/lazy_instance.h"
+#include "base/memory/scoped_ptr.h"
+#include "third_party/icu/source/common/unicode/unistr.h"
+#include "third_party/icu/source/i18n/unicode/plurfmt.h"
+#include "third_party/icu/source/i18n/unicode/plurrule.h"
+#include "ui/base/l10n/time_format.h"
+#include "ui/base/ui_base_export.h"
+
+namespace ui {
+
+struct Pluralities;
+
+// Formatter for a (format, length) combination.  May either be instantiated
+// with four parameters for use in TimeFormat::Simple() or with ten parameters
+// for use in TimeFormat::Detailed().
+class Formatter {
+ public:
+  enum Unit {
+    UNIT_SEC,
+    UNIT_MIN,
+    UNIT_HOUR,
+    UNIT_DAY,
+    UNIT_COUNT  // Enum size counter, not a unit.  Must be last.
+  };
+  enum TwoUnits {
+    TWO_UNITS_MIN_SEC,
+    TWO_UNITS_HOUR_MIN,
+    TWO_UNITS_DAY_HOUR,
+    TWO_UNITS_COUNT      // Enum size counter, not a unit pair.  Must be last.
+  };
+
+  Formatter(const Pluralities& sec_pluralities,
+            const Pluralities& min_pluralities,
+            const Pluralities& hour_pluralities,
+            const Pluralities& day_pluralities);
+
+  Formatter(const Pluralities& sec_pluralities,
+            const Pluralities& min_pluralities,
+            const Pluralities& hour_pluralities,
+            const Pluralities& day_pluralities,
+            const Pluralities& min_sec_pluralities1,
+            const Pluralities& min_sec_pluralities2,
+            const Pluralities& hour_min_pluralities1,
+            const Pluralities& hour_min_pluralities2,
+            const Pluralities& day_hour_pluralities1,
+            const Pluralities& day_hour_pluralities2);
+
+  void Format(Unit unit, int value, icu::UnicodeString& formatted_string) const;
+
+  void Format(TwoUnits units,
+              int value_1,
+              int value_2,
+              icu::UnicodeString& formatted_string) const;
+
+ private:
+  // Create a hard-coded fallback plural format.  This will never be called
+  // unless translators make a mistake.
+  scoped_ptr<icu::PluralFormat> CreateFallbackFormat(
+      const icu::PluralRules& rules,
+      const Pluralities& pluralities) const;
+
+  scoped_ptr<icu::PluralFormat> InitFormat(const Pluralities& pluralities);
+
+  scoped_ptr<icu::PluralFormat> simple_format_[UNIT_COUNT];
+  scoped_ptr<icu::PluralFormat> detailed_format_[TWO_UNITS_COUNT][2];
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(Formatter);
+};
+
+// Class to hold all Formatters, intended to be used in a global LazyInstance.
+class UI_BASE_EXPORT FormatterContainer {
+ public:
+  FormatterContainer();
+  ~FormatterContainer();
+
+  const Formatter* Get(TimeFormat::Format format,
+                       TimeFormat::Length length) const;
+
+  static bool GetFallback() { return force_fallback_; }

[tony, 2014/02/26 20:29:20]

Nit: get_force_fallback()

Or you could just move the bool to be a file static in formatter.cc.  Then you
don't need a getter.  Alternately, this method should be private.

[Thiemo Nagel, 2014/02/26 21:13:34]

I can't make it private because it's used by Formatter, not FormatterContainer
in formatter.cc -- but to move the bool outside of any class seems like a good
idea.

[bartfab (slow), 2014/02/27 17:14:51]

Note that the style guide gives you a choice getween CamelCaps and hacker_style
for simple getters and setters.

+  static void SetFallbackForTesting(bool force_fallback) {

[tony, 2014/02/26 20:29:20]

Nit: set_fallback_for_testing(bool force_fallback)

[Thiemo Nagel, 2014/02/26 21:13:34]

Doesn't apply anymore.

+    force_fallback_ = force_fallback;
+  }
+
+  void Reset() {
+    Shutdown();

[tony, 2014/02/26 20:29:20]

Nit: Move this implementation to the cc file.

[Thiemo Nagel, 2014/02/26 21:13:34]

I've renamed it ResetForTesting() and kept it inside the header file to avoid
code generation in production builds.

+    Initialize();
+  }
+
+ private:
+  void Initialize();
+  void Shutdown();
+
+  scoped_ptr<Formatter>
+      formatter_[TimeFormat::FORMAT_COUNT][TimeFormat::LENGTH_COUNT];
+
+  static bool force_fallback_;
+
+  DISALLOW_COPY_AND_ASSIGN(FormatterContainer);
+};
+
+// Windows compilation requires full definition of FormatterContainer before
+// LazyInstance<FormatterContainter> may be declared.
+extern UI_BASE_EXPORT base::LazyInstance<FormatterContainer> g_container;
+
+}  // namespace ui
+
+#endif