Upstream iOS web code.

ios/web/string_util_unittest.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.

[stuartmorgan, 2014/12/04 23:22:58]

This test file should be added to ios/ios_tests_unit.gyp

(It's really web unit tests, and should be moved/renamed accordingly, but nobody
has gotten around to it. For now we can keep adding tests to it though.)

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ios/web/public/string_util.h"
+
+#include "base/strings/utf_string_conversions.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace web {
+
+// Tests that a regular sentence is clipped correctly.
+TEST(StringByClippingLastWordTest, ClipRegularSentence) {
+  const base::string16 kInput =
+      base::UTF8ToUTF16("\nSome text here and there.");
+  EXPECT_EQ(kInput, GetStringByClippingLastWord(kInput, 100));
+}
+
+// Tests that a long sentence exceeding some length is clipped correctly.
+TEST(StringByClippingLastWordTest, ClipLongSentence) {
+  // An arbitrary length.
+  const size_t kStringLength = 10;
+  base::string16 string(kStringLength, 'a');
+  string.append(base::UTF8ToUTF16(" b cdefghijklmnopqrstuvwxyz"));
+  // The string should be cut at the last whitespace, after the 'b' character.
+  base::string16 result =
+      GetStringByClippingLastWord(string, kStringLength + 3);
+  EXPECT_EQ(kStringLength + 2, result.size());
+  EXPECT_EQ(0u, string.find_first_of(result));
+}
+
+// Tests that a block of text with no space is truncated to kLongStringLength.
+TEST(StringByClippingLastWordTest, ClipLongTextContentNoSpace) {
+  // Very long string.
+  const size_t kLongStringLength = 65536;
+  // A string slightly longer than |kLongStringLength|.
+  base::string16 long_string(kLongStringLength + 10, 'a');
+  // Block of text with no space should be truncated to kLongStringLength.
+  base::string16 result =
+      GetStringByClippingLastWord(long_string, kLongStringLength);
+  EXPECT_EQ(kLongStringLength, result.size());
+  EXPECT_EQ(0u, long_string.find_first_of(result));
+}
+
+}  // namespace web