Inline StringValue into base::Value

base/values.h

 // Copyright (c) 2012 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.
 
 // This file specifies a recursive data storage class called Value intended for
 // storing settings and other persistable data.
 //
 // A Value represents something that can be stored in JSON or passed to/from
 // JavaScript. As such, it is NOT a generalized variant type, since only the
 // types supported by JavaScript/JSON are supported.
@@ skipping 12 matching lines @@
 #include <iosfwd>
 #include <map>
 #include <memory>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/base_export.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
+#include "base/memory/manual_constructor.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_piece.h"
 
 namespace base {
 
 class BinaryValue;
 class DictionaryValue;
 class ListValue;
-class StringValue;
 class Value;
 using FundamentalValue = Value;
+using StringValue = Value;
 
 // The Value class is the base class for Values. A Value can be instantiated
 // via the Create*Value() factory methods, or by directly creating instances of
 // the subclasses.
 //
 // See the file-level comment above for more information.
 class BASE_EXPORT Value {
  public:
   enum class Type {
     NONE = 0,
@@ skipping 10 matching lines @@
   static std::unique_ptr<Value> CreateNullValue();
 
   Value(const Value& that);
   Value(Value&& that);
   Value();  // A null value.
   explicit Value(Type type);
   explicit Value(bool in_bool);
   explicit Value(int in_int);
   explicit Value(double in_double);
 
+  // Value(const char*) and Value(const char16*) are required despite
+  // Value(const std::string&) and Value(const string16&) because otherwise the
+  // compiler will choose the Value(bool) constructor for these arguments.
+  // Value(std::string&&) allow for efficient move construction.
+  // Value(StringPiece) exists due to many callsites passing StringPieces as
+  // arguments.
+  explicit Value(const char* in_string);
+  explicit Value(const std::string& in_string);
+  explicit Value(std::string&& in_string);
+  explicit Value(const char16* in_string);
+  explicit Value(const string16& in_string);
+  explicit Value(StringPiece in_string);
+
   Value& operator=(const Value& that);
   Value& operator=(Value&& that);
 
   virtual ~Value();
 
   // Returns the name for a given |type|.
   static const char* GetTypeName(Type type);
 
   // Returns the type of the value stored by the current Value object.
   // Each type will be implemented by only one subclass of Value, so it's
@@ skipping 10 matching lines @@
   bool is_double() const { return type() == Type::DOUBLE; }
   bool is_string() const { return type() == Type::STRING; }
   bool is_blob() const { return type() == Type::BINARY; }
   bool is_dict() const { return type() == Type::DICTIONARY; }
   bool is_list() const { return type() == Type::LIST; }
 
   // These will all fatally assert if the type doesn't match.
   bool GetBool() const;
   int GetInt() const;
   double GetDouble() const;  // Implicitly converts from int if necessary.
+  const std::string& GetString() const;
 
   // These methods allow the convenient retrieval of the contents of the Value.
   // If the current object can be converted into the given type, the value is
   // returned through the |out_value| parameter and true is returned;
   // otherwise, false is returned and |out_value| is unchanged.
   virtual bool GetAsBoolean(bool* out_value) const;
   virtual bool GetAsInteger(int* out_value) const;
   virtual bool GetAsDouble(double* out_value) const;
   virtual bool GetAsString(std::string* out_value) const;
   virtual bool GetAsString(string16* out_value) const;
@@ skipping 16 matching lines @@
   // Preferred version of DeepCopy. TODO(estade): remove the above.
   std::unique_ptr<Value> CreateDeepCopy() const;
 
   // Compares if two Value objects have equal contents.
   virtual bool Equals(const Value* other) const;
 
   // Compares if two Value objects have equal contents. Can handle NULLs.
   // NULLs are considered equal but different from Value::CreateNullValue().
   static bool Equals(const Value* a, const Value* b);
 
+ protected:
+  // TODO(crbug.com/646113): Make this private once JSONStringValue is removed.
+  Type type_;
+
  private:
-  void InternalCopyFrom(const Value& that);
-
-  Type type_;
+  void InternalCopyFundamentalValue(const Value& that);
+  void InternalCopyConstructFrom(const Value& that);
+  void InternalMoveConstructFrom(Value&& that);
+  void InternalCopyAssignFrom(const Value& that);
+  void InternalMoveAssignFrom(Value&& that);
+  void InternalCleanup();
 
   union {
     bool bool_value_;
     int int_value_;
     double double_value_;
+    ManualConstructor<std::string> string_value_;
   };
 };
 
-class BASE_EXPORT StringValue : public Value {
- public:
-  // Initializes a StringValue with a UTF-8 narrow character string.
-  explicit StringValue(StringPiece in_value);
-
-  // Initializes a StringValue with a string16.
-  explicit StringValue(const string16& in_value);
-
-  ~StringValue() override;
-
-  // Returns |value_| as a pointer or reference.
-  std::string* GetString();
-  const std::string& GetString() const;
-
-  // Overridden from Value:
-  bool GetAsString(std::string* out_value) const override;
-  bool GetAsString(string16* out_value) const override;
-  bool GetAsString(const StringValue** out_value) const override;
-  bool GetAsString(StringPiece* out_value) const override;
-  StringValue* DeepCopy() const override;
-  bool Equals(const Value* other) const override;
-
- private:
-  std::string value_;
-};
-
 class BASE_EXPORT BinaryValue: public Value {
  public:
   // Creates a BinaryValue with a null buffer and size of 0.
   BinaryValue();
 
   // Creates a BinaryValue, taking ownership of the bytes pointed to by
   // |buffer|.
   BinaryValue(std::unique_ptr<char[]> buffer, size_t size);
 
   ~BinaryValue() override;
@@ skipping 350 matching lines @@
                                              std::string* error_str) = 0;
 };
 
 // Stream operator so Values can be used in assertion statements.  In order that
 // gtest uses this operator to print readable output on test failures, we must
 // override each specific type. Otherwise, the default template implementation
 // is preferred over an upcast.
 BASE_EXPORT std::ostream& operator<<(std::ostream& out, const Value& value);
 
 BASE_EXPORT inline std::ostream& operator<<(std::ostream& out,
-                                            const StringValue& value) {
-  return out << static_cast<const Value&>(value);
-}
-
-BASE_EXPORT inline std::ostream& operator<<(std::ostream& out,
                                             const DictionaryValue& value) {
   return out << static_cast<const Value&>(value);
 }
 
 BASE_EXPORT inline std::ostream& operator<<(std::ostream& out,
                                             const ListValue& value) {
   return out << static_cast<const Value&>(value);
 }
 
 // Stream operator so that enum class Types can be used in log statements.
 BASE_EXPORT std::ostream& operator<<(std::ostream& out,
                                      const Value::Type& type);
 
 }  // namespace base
 
 #endif  // BASE_VALUES_H_