Introduce String::fromUTF8Lenient() and use it for cache_name in CacheStorage API.

third_party/WebKit/Source/wtf/text/WTFStringTest.cpp

 /*
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 48 matching lines @@
 }
 
 namespace {
 
 void testNumberToStringECMAScript(double number, const char* reference)
 {
     CString numberString = String::numberToStringECMAScript(number).latin1();
     EXPECT_STREQ(reference, numberString.data());
 }
 
+void testRoundTripConvertSuccess(const UChar* characters, unsigned length)
+{
+    String utf16String(characters, length);
+    EXPECT_FALSE(utf16String.isNull());
+    std::string utf8String(utf16String.utf8().data(), utf16String.utf8().length());
+    String utf16NewString = String::fromUTF8(utf8String.data(), utf8String.length());
+    EXPECT_FALSE(utf16NewString.isNull());
+    EXPECT_TRUE(utf16String == utf16NewString);
+}
+
+void testRoundTripConvertFailure(const UChar* characters, unsigned length)
+{
+    String utf16String(characters, length);
+    EXPECT_FALSE(utf16String.isNull());
+    std::string utf8String(utf16String.utf8().data(), utf16String.utf8().length());
+    String utf16NewString = String::fromUTF8(utf8String.data(), utf8String.length());
+    EXPECT_TRUE(utf16NewString.isNull());
+}
+
+void testRoundTripLenientConvert(const UChar* characters, unsigned length)
+{
+    String utf16String(characters, length);
+    EXPECT_FALSE(utf16String.isNull());
+    std::string utf8String(utf16String.utf8().data(), utf16String.utf8().length());
+    String utf16NewString = String::fromUTF8Lenient(utf8String.data(), utf8String.length());
+    EXPECT_FALSE(utf16NewString.isNull());
+    EXPECT_TRUE(utf16String == utf16NewString);
+}
+
 } // anonymous namespace
 
 TEST(StringTest, NumberToStringECMAScriptBoundaries)
 {
     typedef std::numeric_limits<double> Limits;
 
     // Infinity.
     testNumberToStringECMAScript(Limits::infinity(), "Infinity");
     testNumberToStringECMAScript(-Limits::infinity(), "-Infinity");
 
@@ skipping 315 matching lines @@
 }
 
 TEST(StringTest, Lower)
 {
     EXPECT_STREQ("link", String("LINK").lower().ascii().data());
     EXPECT_STREQ("link", String("lInk").lower().ascii().data());
     EXPECT_STREQ("lin\xE1k", String("lIn\xC1k").lower().latin1().data());
     EXPECT_STREQ("link", String::fromUTF8("LIN\xE2\x84\xAA").lower().utf8().data());
 }
 
+TEST(StringTest, RoundTripConvert)
+{
+    for (UChar uchar = 0; uchar <= 0xD7FF; ++uchar)
+        testRoundTripConvertSuccess(&uchar, 1);
+    // String::fromUTF8() can't convert unpaired surrogates.
+    for (UChar uchar = 0xD800; uchar <= 0xDFFF; ++uchar)
+        testRoundTripConvertFailure(&uchar, 1);
+    for (UChar uchar = 0xE000; uchar != 0; ++uchar)
+        testRoundTripConvertSuccess(&uchar, 1);
+
+    // String::fromUTF8() can't convert word-swapped surrogates.
+    const UChar wordSwappedSurrogate[] = { 0xDC00, 0xD800 };
+    testRoundTripConvertFailure(wordSwappedSurrogate, 2);
+
+    // A correct surrogate pair.
+    const UChar correctSurrogatePair[] = { 0xD83D, 0xDCA9 };
+    testRoundTripConvertSuccess(correctSurrogatePair, 2);
+}
+
+TEST(StringTest, RoundTripLenientConvert)
+{
+    // String::fromUTF8Lenient() can convert all.
+    UChar uchar = 0;
+    do {
+        testRoundTripLenientConvert(&uchar, 1);
+    } while (++uchar);
+
+    // All characters in one string.
+    UChar buffer[0x10000];
+    uchar = 0;
+    do {
+        buffer[uchar] = uchar;
+    } while (++uchar);
+    testRoundTripLenientConvert(buffer, 0x10000);
+
+    // Word-swapped surrogates.
+    const UChar wordSwappedSurrogate[] = { 0xDC00, 0xD800 };
+    testRoundTripLenientConvert(wordSwappedSurrogate, 2);
+
+    // A correct surrogate pair.
+    const UChar correctSurrogatePair[] = { 0xD83D, 0xDCA9 };
+    testRoundTripLenientConvert(correctSurrogatePair, 2);
+}
+
 } // namespace WTF