Expand WTF::StringView's API to be more like StringPiece.

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

Index: third_party/WebKit/Source/wtf/text/StringViewTest.cpp
diff --git a/third_party/WebKit/Source/wtf/text/StringViewTest.cpp b/third_party/WebKit/Source/wtf/text/StringViewTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..522b42a3298a262a73b2e5dedfd5b38dd6497807
--- /dev/null
+++ b/third_party/WebKit/Source/wtf/text/StringViewTest.cpp
@@ -0,0 +1,326 @@
+// Copyright 2016 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 "wtf/text/StringView.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "wtf/text/AtomicString.h"
+#include "wtf/text/StringImpl.h"
+#include "wtf/text/WTFString.h"
+
+namespace WTF {
+
+const char* kChars = "12345";
+const LChar* kChars8 = reinterpret_cast<const LChar*>(kChars);
+const UChar* kChars16 = reinterpret_cast<const UChar*>(u"12345");
+
+TEST(StringViewTest, ConstructionStringImpl8)
+{
+    RefPtr<StringImpl> impl8Bit = StringImpl::create(kChars8, 5);
+
+    // StringView(StringImpl*);
+    ASSERT_TRUE(StringView(impl8Bit.get()).is8Bit());
+    EXPECT_FALSE(StringView(impl8Bit.get()).isNull());
+    EXPECT_EQ(impl8Bit->characters8(), StringView(impl8Bit.get()).characters8());
+    EXPECT_EQ(impl8Bit->length(), StringView(impl8Bit.get()).length());
+    EXPECT_STREQ(kChars, StringView(impl8Bit.get()).toString().utf8().data());
+
+    // StringView(StringImpl*, unsigned offset);
+    ASSERT_TRUE(StringView(impl8Bit.get(), 2).is8Bit());
+    EXPECT_FALSE(StringView(impl8Bit.get(), 2).isNull());
+    EXPECT_EQ(impl8Bit->characters8() + 2, StringView(impl8Bit.get(), 2).characters8());
+    EXPECT_EQ(3u, StringView(impl8Bit.get(), 2).length());
+    EXPECT_EQ(StringView("345"), StringView(impl8Bit.get(), 2));
+    EXPECT_STREQ("345", StringView(impl8Bit.get(), 2).toString().utf8().data());
+
+    // StringView(StringImpl*, unsigned offset, unsigned length);
+    ASSERT_TRUE(StringView(impl8Bit.get(), 2, 1).is8Bit());
+    EXPECT_FALSE(StringView(impl8Bit.get(), 2, 1).isNull());
+    EXPECT_EQ(impl8Bit->characters8() + 2, StringView(impl8Bit.get(), 2, 1).characters8());
+    EXPECT_EQ(1u, StringView(impl8Bit.get(), 2, 1).length());
+    EXPECT_EQ(StringView("3"), StringView(impl8Bit.get(), 2, 1));
+    EXPECT_STREQ("3", StringView(impl8Bit.get(), 2, 1).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionStringImpl16)
+{
+    RefPtr<StringImpl> impl16Bit = StringImpl::create(kChars16, 5);
+
+    // StringView(StringImpl*);
+    ASSERT_FALSE(StringView(impl16Bit.get()).is8Bit());
+    EXPECT_FALSE(StringView(impl16Bit.get()).isNull());
+    EXPECT_EQ(impl16Bit->characters16(), StringView(impl16Bit.get()).characters16());
+    EXPECT_EQ(impl16Bit->length(), StringView(impl16Bit.get()).length());
+    EXPECT_STREQ(kChars, StringView(impl16Bit.get()).toString().utf8().data());
+
+    // StringView(StringImpl*, unsigned offset);
+    ASSERT_FALSE(StringView(impl16Bit.get(), 2).is8Bit());
+    EXPECT_FALSE(StringView(impl16Bit.get(), 2).isNull());
+    EXPECT_EQ(impl16Bit->characters16() + 2, StringView(impl16Bit.get(), 2).characters16());
+    EXPECT_EQ(3u, StringView(impl16Bit.get(), 2).length());
+    EXPECT_EQ(StringView("345"), StringView(impl16Bit.get(), 2));
+    EXPECT_STREQ("345", StringView(impl16Bit.get(), 2).toString().utf8().data());
+
+    // StringView(StringImpl*, unsigned offset, unsigned length);
+    ASSERT_FALSE(StringView(impl16Bit.get(), 2, 1).is8Bit());
+    EXPECT_FALSE(StringView(impl16Bit.get(), 2, 1).isNull());
+    EXPECT_EQ(impl16Bit->characters16() + 2, StringView(impl16Bit.get(), 2, 1).characters16());
+    EXPECT_EQ(1u, StringView(impl16Bit.get(), 2, 1).length());
+    EXPECT_EQ(StringView("3"), StringView(impl16Bit.get(), 2, 1));
+    EXPECT_STREQ("3", StringView(impl16Bit.get(), 2, 1).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionString8)
+{
+    String string8Bit = String(StringImpl::create(kChars8, 5));
+
+    // StringView(const String&);
+    ASSERT_TRUE(StringView(string8Bit).is8Bit());
+    EXPECT_FALSE(StringView(string8Bit).isNull());
+    EXPECT_EQ(string8Bit.characters8(), StringView(string8Bit).characters8());
+    EXPECT_EQ(string8Bit.length(), StringView(string8Bit).length());
+    EXPECT_STREQ(kChars, StringView(string8Bit).toString().utf8().data());
+
+    // StringView(const String&, unsigned offset);
+    ASSERT_TRUE(StringView(string8Bit, 2).is8Bit());
+    EXPECT_FALSE(StringView(string8Bit, 2).isNull());
+    EXPECT_EQ(string8Bit.characters8() + 2, StringView(string8Bit, 2).characters8());
+    EXPECT_EQ(3u, StringView(string8Bit, 2).length());
+    EXPECT_EQ(StringView("345"), StringView(string8Bit, 2));
+    EXPECT_STREQ("345", StringView(string8Bit, 2).toString().utf8().data());
+
+    // StringView(const String&, unsigned offset, unsigned length);
+    ASSERT_TRUE(StringView(string8Bit, 2, 1).is8Bit());
+    EXPECT_FALSE(StringView(string8Bit, 2, 1).isNull());
+    EXPECT_EQ(string8Bit.characters8() + 2, StringView(string8Bit, 2, 1).characters8());
+    EXPECT_EQ(1u, StringView(string8Bit, 2, 1).length());
+    EXPECT_EQ(StringView("3"), StringView(string8Bit, 2, 1));
+    EXPECT_STREQ("3", StringView(string8Bit, 2, 1).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionString16)
+{
+    String string16Bit = String(StringImpl::create(kChars16, 5));
+
+    // StringView(const String&);
+    ASSERT_FALSE(StringView(string16Bit).is8Bit());
+    EXPECT_FALSE(StringView(string16Bit).isNull());
+    EXPECT_EQ(string16Bit.characters16(), StringView(string16Bit).characters16());
+    EXPECT_EQ(string16Bit.length(), StringView(string16Bit).length());
+    EXPECT_STREQ(kChars, StringView(string16Bit).toString().utf8().data());
+
+    // StringView(const String&, unsigned offset);
+    ASSERT_FALSE(StringView(string16Bit, 2).is8Bit());
+    EXPECT_FALSE(StringView(string16Bit, 2).isNull());
+    EXPECT_EQ(string16Bit.characters16() + 2, StringView(string16Bit, 2).characters16());
+    EXPECT_EQ(3u, StringView(string16Bit, 2).length());
+    EXPECT_EQ(StringView("345"), StringView(string16Bit, 2));
+    EXPECT_STREQ("345", StringView(string16Bit, 2).toString().utf8().data());
+
+    // StringView(const String&, unsigned offset, unsigned length);
+    ASSERT_FALSE(StringView(string16Bit, 2, 1).is8Bit());
+    EXPECT_FALSE(StringView(string16Bit, 2, 1).isNull());
+    EXPECT_EQ(string16Bit.characters16() + 2, StringView(string16Bit, 2, 1).characters16());
+    EXPECT_EQ(1u, StringView(string16Bit, 2, 1).length());
+    EXPECT_EQ(StringView("3"), StringView(string16Bit, 2, 1));
+    EXPECT_STREQ("3", StringView(string16Bit, 2, 1).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionAtomicString8)
+{
+    AtomicString atom8Bit = AtomicString(StringImpl::create(kChars8, 5));
+
+    // StringView(const AtomicString&);
+    ASSERT_TRUE(StringView(atom8Bit).is8Bit());
+    EXPECT_FALSE(StringView(atom8Bit).isNull());
+    EXPECT_EQ(atom8Bit.characters8(), StringView(atom8Bit).characters8());
+    EXPECT_EQ(atom8Bit.length(), StringView(atom8Bit).length());
+    EXPECT_STREQ(kChars, StringView(atom8Bit).toString().utf8().data());
+
+    // StringView(const AtomicString&, unsigned offset);
+    ASSERT_TRUE(StringView(atom8Bit, 2).is8Bit());
+    EXPECT_FALSE(StringView(atom8Bit, 2).isNull());
+    EXPECT_EQ(atom8Bit.characters8() + 2, StringView(atom8Bit, 2).characters8());
+    EXPECT_EQ(3u, StringView(atom8Bit, 2).length());
+    EXPECT_EQ(StringView("345"), StringView(atom8Bit, 2));
+    EXPECT_STREQ("345", StringView(atom8Bit, 2).toString().utf8().data());
+
+    // StringView(const AtomicString&, unsigned offset, unsigned length);
+    ASSERT_TRUE(StringView(atom8Bit, 2, 1).is8Bit());
+    EXPECT_FALSE(StringView(atom8Bit, 2, 1).isNull());
+    EXPECT_EQ(atom8Bit.characters8() + 2, StringView(atom8Bit, 2, 1).characters8());
+    EXPECT_EQ(1u, StringView(atom8Bit, 2, 1).length());
+    EXPECT_EQ(StringView("3"), StringView(atom8Bit, 2, 1));
+    EXPECT_STREQ("3", StringView(atom8Bit, 2, 1).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionAtomicString16)
+{
+    AtomicString atom16Bit = AtomicString(StringImpl::create(kChars16, 5));
+
+    // StringView(const AtomicString&);
+    ASSERT_FALSE(StringView(atom16Bit).is8Bit());
+    EXPECT_FALSE(StringView(atom16Bit).isNull());
+    EXPECT_EQ(atom16Bit.characters16(), StringView(atom16Bit).characters16());
+    EXPECT_EQ(atom16Bit.length(), StringView(atom16Bit).length());
+    EXPECT_STREQ(kChars, StringView(atom16Bit).toString().utf8().data());
+
+    // StringView(const AtomicString&, unsigned offset);
+    ASSERT_FALSE(StringView(atom16Bit, 2).is8Bit());
+    EXPECT_FALSE(StringView(atom16Bit, 2).isNull());
+    EXPECT_EQ(atom16Bit.characters16() + 2, StringView(atom16Bit, 2).characters16());
+    EXPECT_EQ(3u, StringView(atom16Bit, 2).length());
+    EXPECT_EQ(StringView("345"), StringView(atom16Bit, 2));
+    EXPECT_STREQ("345", StringView(atom16Bit, 2).toString().utf8().data());
+
+    // StringView(const AtomicString&, unsigned offset, unsigned length);
+    ASSERT_FALSE(StringView(atom16Bit, 2, 1).is8Bit());
+    EXPECT_FALSE(StringView(atom16Bit, 2, 1).isNull());
+    EXPECT_EQ(atom16Bit.characters16() + 2, StringView(atom16Bit, 2, 1).characters16());
+    EXPECT_EQ(1u, StringView(atom16Bit, 2, 1).length());
+    EXPECT_EQ(StringView("3"), StringView(atom16Bit, 2, 1));
+    EXPECT_STREQ("3", StringView(atom16Bit, 2, 1).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionStringView8)
+{
+    StringView view8Bit = StringView(kChars8, 5);
+
+    // StringView(StringView&);
+    ASSERT_TRUE(StringView(view8Bit).is8Bit());
+    EXPECT_FALSE(StringView(view8Bit).isNull());
+    EXPECT_EQ(view8Bit.characters8(), StringView(view8Bit).characters8());
+    EXPECT_EQ(view8Bit.length(), StringView(view8Bit).length());
+    EXPECT_STREQ(kChars, StringView(view8Bit).toString().utf8().data());
+
+    // StringView(const StringView&, unsigned offset);
+    ASSERT_TRUE(StringView(view8Bit, 2).is8Bit());
+    EXPECT_FALSE(StringView(view8Bit, 2).isNull());
+    EXPECT_EQ(view8Bit.characters8() + 2, StringView(view8Bit, 2).characters8());
+    EXPECT_EQ(3u, StringView(view8Bit, 2).length());
+    EXPECT_EQ(StringView("345"), StringView(view8Bit, 2));
+    EXPECT_STREQ("345", StringView(view8Bit, 2).toString().utf8().data());
+
+    // StringView(const StringView&, unsigned offset, unsigned length);
+    ASSERT_TRUE(StringView(view8Bit, 2, 1).is8Bit());
+    EXPECT_FALSE(StringView(view8Bit, 2, 1).isNull());
+    EXPECT_EQ(view8Bit.characters8() + 2, StringView(view8Bit, 2, 1).characters8());
+    EXPECT_EQ(1u, StringView(view8Bit, 2, 1).length());
+    EXPECT_EQ(StringView("3"), StringView(view8Bit, 2, 1));
+    EXPECT_STREQ("3", StringView(view8Bit, 2, 1).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionStringView16)
+{
+    StringView view16Bit = StringView(kChars16, 5);
+
+    // StringView(StringView&);
+    ASSERT_FALSE(StringView(view16Bit).is8Bit());
+    EXPECT_FALSE(StringView(view16Bit).isNull());
+    EXPECT_EQ(view16Bit.characters16(), StringView(view16Bit).characters16());
+    EXPECT_EQ(view16Bit.length(), StringView(view16Bit).length());
+    EXPECT_EQ(kChars, StringView(view16Bit).toString());
+
+    // StringView(const StringView&, unsigned offset);
+    ASSERT_FALSE(StringView(view16Bit, 2).is8Bit());
+    EXPECT_FALSE(StringView(view16Bit, 2).isNull());
+    EXPECT_EQ(view16Bit.characters16() + 2, StringView(view16Bit, 2).characters16());
+    EXPECT_EQ(3u, StringView(view16Bit, 2).length());
+    EXPECT_EQ(StringView("345"), StringView(view16Bit, 2));
+    EXPECT_STREQ("345", StringView(view16Bit, 2).toString().utf8().data());
+
+    // StringView(const StringView&, unsigned offset, unsigned length);
+    ASSERT_FALSE(StringView(view16Bit, 2, 1).is8Bit());
+    EXPECT_FALSE(StringView(view16Bit, 2, 1).isNull());
+    EXPECT_EQ(view16Bit.characters16() + 2, StringView(view16Bit, 2, 1).characters16());
+    EXPECT_EQ(1u, StringView(view16Bit, 2, 1).length());
+    EXPECT_EQ(StringView("3"), StringView(view16Bit, 2, 1));
+    EXPECT_STREQ("3", StringView(view16Bit, 2, 1).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionLiteral8)
+{
+    // StringView(const LChar* chars);
+    ASSERT_TRUE(StringView(kChars8).is8Bit());
+    EXPECT_FALSE(StringView(kChars8).isNull());
+    EXPECT_EQ(kChars8, StringView(kChars8).characters8());
+    EXPECT_EQ(5u, StringView(kChars8).length());
+    EXPECT_STREQ(kChars, StringView(kChars8).toString().utf8().data());
+
+    // StringView(const char* chars);
+    ASSERT_TRUE(StringView(kChars).is8Bit());
+    EXPECT_FALSE(StringView(kChars).isNull());
+    EXPECT_EQ(kChars8, StringView(kChars).characters8());
+    EXPECT_EQ(5u, StringView(kChars).length());
+    EXPECT_STREQ(kChars, StringView(kChars).toString().utf8().data());
+
+    // StringView(const LChar* chars, unsigned length);
+    ASSERT_TRUE(StringView(kChars8, 2).is8Bit());
+    EXPECT_FALSE(StringView(kChars8, 2).isNull());
+    EXPECT_EQ(2u, StringView(kChars8, 2).length());
+    EXPECT_EQ(StringView("12"), StringView(kChars8, 2));
+    EXPECT_STREQ("12", StringView(kChars8, 2).toString().utf8().data());
+
+    // StringView(const char* chars, unsigned length);
+    ASSERT_TRUE(StringView(kChars, 2).is8Bit());
+    EXPECT_FALSE(StringView(kChars, 2).isNull());
+    EXPECT_EQ(2u, StringView(kChars, 2).length());
+    EXPECT_EQ(StringView("12"), StringView(kChars, 2));
+    EXPECT_STREQ("12", StringView(kChars, 2).toString().utf8().data());
+}
+
+TEST(StringViewTest, ConstructionLiteral16)
+{
+    // StringView(const UChar* chars);
+    ASSERT_FALSE(StringView(kChars16).is8Bit());
+    EXPECT_FALSE(StringView(kChars16).isNull());
+    EXPECT_EQ(kChars16, StringView(kChars16).characters16());
+    EXPECT_EQ(5u, StringView(kChars16).length());
+    EXPECT_EQ(String(kChars16), StringView(kChars16).toString().utf8().data());
+
+    // StringView(const UChar* chars, unsigned length);
+    ASSERT_FALSE(StringView(kChars16, 2).is8Bit());
+    EXPECT_FALSE(StringView(kChars16, 2).isNull());
+    EXPECT_EQ(kChars16, StringView(kChars16, 2).characters16());
+    EXPECT_EQ(StringView("12"), StringView(kChars16, 2));
+    EXPECT_EQ(StringView(reinterpret_cast<const UChar*>(u"12")), StringView(kChars16, 2));
+    EXPECT_EQ(2u, StringView(kChars16, 2).length());
+    EXPECT_EQ(String("12"), StringView(kChars16, 2).toString());
+}
+
+TEST(StringViewTest, IsEmpty)
+{
+    EXPECT_FALSE(StringView(kChars).isEmpty());
+    EXPECT_TRUE(StringView(kChars, 0).isEmpty());
+    EXPECT_FALSE(StringView(String(kChars)).isEmpty());
+    EXPECT_TRUE(StringView(String(kChars), 5).isEmpty());
+    EXPECT_TRUE(StringView(String(kChars), 4, 0).isEmpty());
+    EXPECT_TRUE(StringView().isEmpty());
+    EXPECT_TRUE(StringView("").isEmpty());
+    EXPECT_TRUE(StringView(reinterpret_cast<const UChar*>(u"")).isEmpty());
+    EXPECT_FALSE(StringView(kChars16).isEmpty());
+}
+
+TEST(StringViewTest, ToString)
+{
+    // Empty string optimization.
+    EXPECT_EQ(emptyString().impl(), StringView("").toString().impl());
+    // NOTE: All the construction tests also check toString().
+}
+
+TEST(StringViewTest, NullString)
+{
+    EXPECT_TRUE(StringView().isNull());
+    EXPECT_TRUE(StringView(String()).isNull());
+    EXPECT_TRUE(StringView(AtomicString()).isNull());
+    EXPECT_TRUE(StringView(static_cast<const char*>(nullptr)).isNull());
+    StringView view(kChars);
+    EXPECT_FALSE(view.isNull());
+    view.clear();
+    EXPECT_TRUE(view.isNull());
+    EXPECT_EQ(String(), StringView());
+    EXPECT_TRUE(StringView().toString().isNull());
+}
+
+} // namespace WTF