base: Make TimeDurationFormat* report failures.

base/i18n/time_formatting.h

 // 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.
 
 // Basic time formatting methods.  These methods use the current locale
 // formatting for displaying the time.
 
 #ifndef BASE_I18N_TIME_FORMATTING_H_
 #define BASE_I18N_TIME_FORMATTING_H_
 
@@ skipping 28 matching lines @@
 
 // Date formats from third_party/icu/source/i18n/unicode/udat.h. Add more as
 // necessary.
 enum DateFormat {
   // November 2007
   DATE_FORMAT_YEAR_MONTH,
   // Tuesday, 7 November
   DATE_FORMAT_MONTH_WEEKDAY_DAY,
 };
 
+// TODO(derat@chromium.org): Update all of these functions to return boolean
+// "success" values and use out-params for formatted strings:
+// http://crbug.com/698802
+
 // Returns the time of day, e.g., "3:07 PM".
 BASE_I18N_EXPORT string16 TimeFormatTimeOfDay(const Time& time);
 
 // Returns the time of day in 24-hour clock format with millisecond accuracy,
 // e.g., "15:07:30.568"
 BASE_I18N_EXPORT string16 TimeFormatTimeOfDayWithMilliseconds(const Time& time);
 
 // Returns the time of day in the specified hour clock type. e.g.
 // "3:07 PM" (type == k12HourClock, ampm == kKeepAmPm).
 // "3:07"    (type == k12HourClock, ampm == kDropAmPm).
@@ skipping 29 matching lines @@
 BASE_I18N_EXPORT string16 TimeFormatFriendlyDate(const Time& time);
 
 // Formats a time using a skeleton to produce a format for different locales
 // when an unusual time format is needed, e.g. "Feb. 2, 18:00".
 //
 // See http://userguide.icu-project.org/formatparse/datetime for details.
 BASE_I18N_EXPORT string16 TimeFormatWithPattern(const Time& time,
                                                 const char* pattern);
 
 // Formats a time duration of hours and minutes into various formats, e.g.,
-// "3:07" or "3 hours, 7 minutes".  See DurationFormatWidth for details.
+// "3:07" or "3 hours, 7 minutes", and returns true on success. See
+// DurationFormatWidth for details.
 //
 // Please don't use width = DURATION_WIDTH_NUMERIC when the time duration
 // can possibly be larger than 24h, as the hour value will be cut below 24
 // after formatting.
 // TODO(chengx): fix function output when width = DURATION_WIDTH_NUMERIC
 // (http://crbug.com/675791)
-BASE_I18N_EXPORT string16 TimeDurationFormat(const TimeDelta time,
-                                             const DurationFormatWidth width);
+BASE_I18N_EXPORT bool TimeDurationFormat(const TimeDelta time,

[bruthig, 2017/03/06 21:12:38]

Consider using the WARN_UNUSED_RESULT macro here.

[Daniel Erat, 2017/03/06 21:24:32]

sure, sounds good.

+                                         const DurationFormatWidth width,
+                                         string16* out);
 
 // Formats a time duration of hours, minutes and seconds into various formats,
-// e.g., "3:07:30" or "3 hours, 7 minutes, 30 seconds". See DurationFormatWidth
-// for details.
+// e.g., "3:07:30" or "3 hours, 7 minutes, 30 seconds", and returns true on
+// success. See DurationFormatWidth for details.
 //
 // Please don't use width = DURATION_WIDTH_NUMERIC when the time duration
 // can possibly be larger than 24h, as the hour value will be cut below 24
 // after formatting.
 // TODO(chengx): fix function output when width = DURATION_WIDTH_NUMERIC
 // (http://crbug.com/675791)
-BASE_I18N_EXPORT string16
-TimeDurationFormatWithSeconds(const TimeDelta time,
-                              const DurationFormatWidth width);
+BASE_I18N_EXPORT bool TimeDurationFormatWithSeconds(
+    const TimeDelta time,
+    const DurationFormatWidth width,
+    string16* out);
 
 // Formats a date interval into various formats, e.g. "2 December - 4 December"
 // or "March 2016 - December 2016". See DateFormat for details.
 BASE_I18N_EXPORT string16 DateIntervalFormat(const Time& begin_time,
                                              const Time& end_time,
                                              DateFormat format);
 
 // Gets the hour clock type of the current locale. e.g.
 // k12HourClock (en-US).
 // k24HourClock (en-GB).
 BASE_I18N_EXPORT HourClockType GetHourClockType();
 
 }  // namespace base
 
 #endif  // BASE_I18N_TIME_FORMATTING_H_