Allow WebString.utf8() to take UTF8ConversionMode

third_party/WebKit/Source/platform/exported/WebStringTest.cpp

+// Copyright 2017 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 "public/platform/WebString.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "wtf/text/WTFString.h"
+
+namespace blink {
+
+TEST(WebStringTest, UTF8ConversionRoundTrip) {
+  // Valid characters.
+  for (UChar uchar = 0; uchar <= 0xD7FF; ++uchar) {
+    WebString utf16String(&uchar, 1);
+    std::string utf8String(utf16String.utf8());
+    WebString utf16NewString =
+        WebString::fromUTF8(utf8String.data(), utf8String.length());
+    EXPECT_FALSE(utf16NewString.isNull());
+    EXPECT_TRUE(utf16String == utf16NewString);
+  }
+
+  // Unpaired surrogates.
+  for (UChar uchar = 0xD800; uchar <= 0xDFFF; ++uchar) {
+    WebString utf16String(&uchar, 1);
+
+    // Conversion with Strict mode results in an empty string.
+    std::string utf8String(
+        utf16String.utf8(WebString::UTF8ConversionMode::kStrict));
+    EXPECT_TRUE(utf8String.empty());
+
+    // Unpaired surrogates can't be converted back in Lenient mode.
+    utf8String = utf16String.utf8(WebString::UTF8ConversionMode::kLenient);
+    EXPECT_FALSE(utf8String.empty());
+    WebString utf16NewString =
+        WebString::fromUTF8(utf8String.data(), utf8String.length());
+    EXPECT_TRUE(utf16NewString.isNull());
+
+    // Round-trip works with StrictReplacingErrorsWithFFFD mode.
+    utf8String = utf16String.utf8(
+        WebString::UTF8ConversionMode::kStrictReplacingErrorsWithFFFD);
+    EXPECT_FALSE(utf8String.empty());
+    utf16NewString =
+        WebString::fromUTF8(utf8String.data(), utf8String.length());
+    EXPECT_FALSE(utf16NewString.isNull());
+    EXPECT_FALSE(utf16String == utf16NewString);
+  }
+}
+
+}  // namespace blink