Add a percent format example

base/i18n/message_formatter_unittest.cc

 // Copyright 2015 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/message_formatter.h"
 
 #include <memory>
 
 #include "base/i18n/rtl.h"
 #include "base/strings/string_piece.h"
@@ skipping 120 matching lines @@
   EXPECT_EQ("The cert for example.com expired yesterday." + second_sentence,
             result);
   result = UTF16ToASCII(MessageFormatter::FormatWithNumberedArgs(
       pattern, "example.com", 15, now));
   EXPECT_EQ("The cert for example.com expired 15 days ago." + second_sentence,
             result);
 }
 
 TEST_F(MessageFormatterTest, DateTimeAndNumber) {
   // Note that using 'mph' for all locales is not a good i18n practice.
+  // For various ways to format numbers, see
+  // http://icu-project.org/apiref/icu4c/classicu_1_1MessageFormat.html and
+  // http://icu-project.org/apiref/icu4c/classicu_1_1DecimalFormat.html
   const string16 pattern = ASCIIToUTF16(
       "At {0,time, short} on {0,date, medium}, "
       "there was {1} at building {2,number,integer}. "
-      "The speed of the wind was {3,number,###.#} mph.");
+      "The speed of the wind was {3,number,###.#} mph."
+      "It was a new record {4,number,percent} higher than the previous."
+      "It was a new record {4,number,##.#%} higher than the previous."
+      // padding example: '*' followed by a padding symbol.
+      "We were given {5,number,integer}:{6,number,*0##} for evacuation.");
 
   using icu::DateFormat;
   std::unique_ptr<DateFormat> tf(
       DateFormat::createTimeInstance(DateFormat::SHORT));
   std::unique_ptr<DateFormat> df(
       DateFormat::createDateInstance(DateFormat::MEDIUM));
 
   base::Time now = base::Time::Now();
   std::string expected = "At ";
   AppendFormattedDateTime(tf, now, &expected);
   expected.append(" on ");
   AppendFormattedDateTime(df, now, &expected);
   expected.append(", there was an explosion at building 3. "
-                  "The speed of the wind was 37.4 mph.");
+                  "The speed of the wind was 37.4 mph."
+                  "It was a new record 6% higher than the previous."
+                  "It was a new record 5.8% higher than the previous."
+                  "We were given 3:05 for evacuation.");
 
   EXPECT_EQ(expected, UTF16ToASCII(MessageFormatter::FormatWithNumberedArgs(
-      pattern, now, "an explosion", 3, 37.413)));
+      pattern, now, "an explosion", 3, 37.413, 0.0578, 3, 5)));
 }
 
 TEST_F(MessageFormatterTest, SelectorSingleOrMultiple) {
   const string16 pattern = ASCIIToUTF16(
       "{0, select,"
       "single {Select a file to upload.}"
       "multiple {Select files to upload.}"
       "other {UNUSED}}");
 
   std::string result = UTF16ToASCII(MessageFormatter::FormatWithNumberedArgs(
       pattern, "single"));
   EXPECT_EQ("Select a file to upload.", result);
   result = UTF16ToASCII(MessageFormatter::FormatWithNumberedArgs(
       pattern, "multiple"));
   EXPECT_EQ("Select files to upload.", result);
 
   // fallback if a parameter is not selectors specified in the message pattern.
   result = UTF16ToASCII(MessageFormatter::FormatWithNumberedArgs(
       pattern, "foobar"));
   EXPECT_EQ("UNUSED", result);
 }
 
 }  // namespace i18n
 }  // namespace base