Move Capitalize function to platform/text

This patch moves Capitalize (titlecase) function from LayoutText
to platform/text in order to share with LayoutNG.

Bug: 636993
Change-Id: I1d0e78139424a20d4184976d1f920c75fc8190ac
Reviewed-on: https://chromium-review.googlesource.com/1047925Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#557113}

third_party/blink/renderer/core/layout/layout_text.cc

@@ -60,6 +60,7 @@
 #include "third_party/blink/renderer/platform/runtime_enabled_features.h"
 #include "third_party/blink/renderer/platform/scheduler/public/thread_scheduler.h"
 #include "third_party/blink/renderer/platform/text/bidi_resolver.h"
+#include "third_party/blink/renderer/platform/text/capitalize.h"
 #include "third_party/blink/renderer/platform/text/character.h"
 #include "third_party/blink/renderer/platform/text/hyphenation.h"
 #include "third_party/blink/renderer/platform/text/text_break_iterator.h"
@@ -112,51 +113,6 @@ class SecureTextTimer final : public TimerBase {
   int last_typed_character_offset_;
 };
 
-static void MakeCapitalized(String* string, UChar previous) {
-  if (string->IsNull())
-    return;
-
-  unsigned length = string->length();
-  const StringImpl& input = *string->Impl();
-
-  CHECK_LT(length, std::numeric_limits<unsigned>::max());
-  StringBuffer<UChar> string_with_previous(length + 1);
-  string_with_previous[0] =
-      previous == kNoBreakSpaceCharacter ? kSpaceCharacter : previous;
-  for (unsigned i = 1; i < length + 1; i++) {
-    // Replace &nbsp with a real space since ICU no longer treats &nbsp as a
-    // word separator.
-    if (input[i - 1] == kNoBreakSpaceCharacter)
-      string_with_previous[i] = kSpaceCharacter;
-    else
-      string_with_previous[i] = input[i - 1];
-  }
-
-  TextBreakIterator* boundary =
-      WordBreakIterator(string_with_previous.Characters(), length + 1);
-  if (!boundary)
-    return;
-
-  StringBuilder result;
-  result.ReserveCapacity(length);
-
-  int32_t end_of_word;
-  int32_t start_of_word = boundary->first();
-  for (end_of_word = boundary->next(); end_of_word != kTextBreakDone;
-       start_of_word = end_of_word, end_of_word = boundary->next()) {
-    if (start_of_word) {  // Ignore first char of previous string
-      result.Append(
-          input[start_of_word - 1] == kNoBreakSpaceCharacter
-              ? kNoBreakSpaceCharacter
-              : WTF::Unicode::ToTitleCase(string_with_previous[start_of_word]));
-    }
-    for (int i = start_of_word + 1; i < end_of_word; i++)
-      result.Append(input[i - 1]);
-  }
-
-  *string = result.ToString();
-}
-
 LayoutText::LayoutText(Node* node, scoped_refptr<StringImpl> str)
     : LayoutObject(node),
       has_tab_(false),
@@ -1717,7 +1673,7 @@ void ApplyTextTransform(const ComputedStyle* style,
     case ETextTransform::kNone:
       break;
     case ETextTransform::kCapitalize:
-      MakeCapitalized(&text, previous_character);
+      text = Capitalize(text, previous_character);
       break;
     case ETextTransform::kUppercase:
       text = text.UpperUnicode(style->Locale());

third_party/blink/renderer/platform/BUILD.gn

@@ -1357,6 +1357,8 @@ jumbo_component("platform") {
     "text/bidi_run_list.h",
     "text/bidi_text_run.cc",
     "text/bidi_text_run.h",
+    "text/capitalize.cc",
+    "text/capitalize.h",
     "text/character.cc",
     "text/character.h",
     "text/character_emoji.cc",
@@ -1889,6 +1891,7 @@ jumbo_source_set("blink_platform_unittests_sources") {
     "testing/tree_test_helpers.h",
     "text/bidi_resolver_test.cc",
     "text/bidi_test_harness.h",
+    "text/capitalize_test.cc",
     "text/character_test.cc",
     "text/date_time_format_test.cc",
     "text/hyphenation_test.cc",

third_party/blink/renderer/platform/text/capitalize.cc

+// Copyright 2018 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/blink/renderer/platform/text/capitalize.h"
+
+#include "third_party/blink/renderer/platform/text/text_break_iterator.h"
+#include "third_party/blink/renderer/platform/wtf/text/string_buffer.h"
+#include "third_party/blink/renderer/platform/wtf/text/string_builder.h"
+#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"
+
+namespace blink {
+
+String Capitalize(const String& string, UChar previous_character) {
+  if (string.IsNull())
+    return string;
+
+  unsigned length = string.length();
+  const StringImpl& input = *string.Impl();
+
+  CHECK_LT(length, std::numeric_limits<unsigned>::max());
+  StringBuffer<UChar> string_with_previous(length + 1);
+  string_with_previous[0] = previous_character == kNoBreakSpaceCharacter
+                                ? kSpaceCharacter
+                                : previous_character;
+  for (unsigned i = 1; i < length + 1; i++) {
+    // Replace &nbsp with a real space since ICU no longer treats &nbsp as a
+    // word separator.
+    if (input[i - 1] == kNoBreakSpaceCharacter)
+      string_with_previous[i] = kSpaceCharacter;
+    else
+      string_with_previous[i] = input[i - 1];
+  }
+
+  TextBreakIterator* boundary =
+      WordBreakIterator(string_with_previous.Characters(), length + 1);
+  if (!boundary)
+    return string;
+
+  StringBuilder result;
+  result.ReserveCapacity(length);
+
+  int32_t end_of_word;
+  int32_t start_of_word = boundary->first();
+  for (end_of_word = boundary->next(); end_of_word != kTextBreakDone;
+       start_of_word = end_of_word, end_of_word = boundary->next()) {
+    if (start_of_word) {  // Ignore first char of previous string
+      result.Append(
+          input[start_of_word - 1] == kNoBreakSpaceCharacter
+              ? kNoBreakSpaceCharacter
+              : WTF::Unicode::ToTitleCase(string_with_previous[start_of_word]));
+    }
+    for (int i = start_of_word + 1; i < end_of_word; i++)
+      result.Append(input[i - 1]);
+  }
+
+  return result.ToString();
+}
+
+}  // namespace blink

third_party/blink/renderer/platform/text/capitalize.h

+// Copyright 2018 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.
+
+#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_TEXT_CAPITALIZE_H_
+#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_TEXT_CAPITALIZE_H_
+
+#include <unicode/utypes.h>
+#include "third_party/blink/renderer/platform/platform_export.h"
+#include "third_party/blink/renderer/platform/wtf/forward.h"
+
+namespace blink {
+
+// Capitalize (titlecase) each word of a string.
+// https://drafts.csswg.org/css-text-3/#valdef-text-transform-capitalize
+PLATFORM_EXPORT String Capitalize(const String&,
+                                  UChar previous_character = ' ');
+
+}  // namespace blink
+
+#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_TEXT_CAPITALIZE_H_

third_party/blink/renderer/platform/text/capitalize_test.cc

+// Copyright 2018 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/blink/renderer/platform/text/capitalize.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "third_party/blink/renderer/platform/text/character.h"
+#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"
+
+namespace blink {
+
+struct CapitalizeTestData {
+  String input;
+  String expected;
+  UChar previous_character = kSpaceCharacter;
+};
+
+class CapitalizeTest : public testing::Test,
+                       public testing::WithParamInterface<CapitalizeTestData> {
+};
+
+INSTANTIATE_TEST_CASE_P(CapitalizeTest,
+                        CapitalizeTest,
+                        testing::Values(CapitalizeTestData{String(), String()},
+                                        CapitalizeTestData{"", ""},
+                                        CapitalizeTestData{"hello, world",
+                                                           "Hello, World"}));
+
+TEST_P(CapitalizeTest, Data) {
+  const auto& data = GetParam();
+  EXPECT_EQ(data.expected, Capitalize(data.input, data.previous_character));
+}
+
+}  // namespace blink