Merge pull request open-source-parsers#267 from cdunn2001/moveSemantics

move ctors

Author: cdunn2001

include/json/config.h

@@ -56,30 +56,59 @@
 // Storages, and 64 bits integer support is disabled.
 // #define JSON_NO_INT64 1
 
-#if defined(_MSC_VER) && _MSC_VER <= 1200 // MSVC 6
+#if defined(_MSC_VER) // MSVC
+#  if _MSC_VER <= 1200 // MSVC 6
     // Microsoft Visual Studio 6 only support conversion from __int64 to double
     // (no conversion from unsigned __int64).
-    #define JSON_USE_INT64_DOUBLE_CONVERSION 1
+#    define JSON_USE_INT64_DOUBLE_CONVERSION 1
     // Disable warning 4786 for VS6 caused by STL (identifier was truncated to '255'
     // characters in the debug information)
     // All projects I've ever seen with VS6 were using this globally (not bothering
     // with pragma push/pop).
 #    pragma warning(disable : 4786)
-#endif // if defined(_MSC_VER)  &&  _MSC_VER < 1200 // MSVC 6
+#  endif // MSVC 6
 
-#if defined(_MSC_VER) && _MSC_VER >= 1500 // MSVC 2008
+#  if _MSC_VER >= 1500 // MSVC 2008
     /// Indicates that the following function is deprecated.
-#define JSONCPP_DEPRECATED(message) __declspec(deprecated(message))
-#elif defined(__clang__) && defined(__has_feature)
-#if __has_feature(attribute_deprecated_with_message)
-#define JSONCPP_DEPRECATED(message)  __attribute__ ((deprecated(message)))
-#endif
-#elif defined(__GNUC__) &&  (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5))
-#define JSONCPP_DEPRECATED(message)  __attribute__ ((deprecated(message)))
-#elif defined(__GNUC__) &&  (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))
-#define JSONCPP_DEPRECATED(message)  __attribute__((__deprecated__))
+#    define JSONCPP_DEPRECATED(message) __declspec(deprecated(message))
+#  endif
+
+#endif // defined(_MSC_VER)
+
+
+#ifndef JSON_HAS_RVALUE_REFERENCES
+
+#if defined(_MSC_VER) && _MSC_VER >= 1600 // MSVC >= 2010
+#define JSON_HAS_RVALUE_REFERENCES 1
+#endif // MSVC >= 2010
+
+#ifdef __clang__
+#if __has_feature(cxx_rvalue_references)
+#define JSON_HAS_RVALUE_REFERENCES 1
+#endif  // has_feature
+
+#elif defined __GNUC__ // not clang (gcc comes later since clang emulates gcc)
+#if defined(__GXX_EXPERIMENTAL_CXX0X__) || (__cplusplus >= 201103L)
+#define JSON_HAS_RVALUE_REFERENCES 1
+#endif  // GXX_EXPERIMENTAL
+
+#endif // __clang__ || __GNUC__
+
+#endif // not defined JSON_HAS_RVALUE_REFERENCES
+
+#ifndef JSON_HAS_RVALUE_REFERENCES
+#define JSON_HAS_RVALUE_REFERENCES 0
 #endif
 
+#ifdef __clang__
+#elif defined __GNUC__ // not clang (gcc comes later since clang emulates gcc)
+#  if (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5))
+#    define JSONCPP_DEPRECATED(message)  __attribute__ ((deprecated(message)))
+#  elif (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))
+#    define JSONCPP_DEPRECATED(message)  __attribute__((__deprecated__))
+#  endif  // GNUC version
+#endif // __clang__ || __GNUC__
+
 #if !defined(JSONCPP_DEPRECATED)
 #define JSONCPP_DEPRECATED(message)
 #endif // if !defined(JSONCPP_DEPRECATED)

include/json/value.h

@@ -212,6 +212,9 @@ class JSON_API Value {
     CZString(ArrayIndex index);
     CZString(char const* str, unsigned length, DuplicationPolicy allocate);
     CZString(CZString const& other);
+#if JSON_HAS_RVALUE_REFERENCES
+    CZString(CZString&& other);
+#endif
     ~CZString();
     CZString& operator=(CZString other);
     bool operator<(CZString const& other) const;
@@ -294,6 +297,10 @@ Json::Value obj_value(Json::objectValue); // {}
   Value(bool value);
   /// Deep copy.
   Value(const Value& other);
+#if JSON_HAS_RVALUE_REFERENCES
+  /// Move constructor
+  Value(Value&& other);
+#endif
   ~Value();
 
   /// Deep copy, then swap(other).

src/lib_json/json_value.cpp

@@ -218,8 +218,7 @@ void Value::CommentInfo::setComment(const char* text, size_t len) {
 Value::CZString::CZString(ArrayIndex aindex) : cstr_(0), index_(aindex) {}
 
 Value::CZString::CZString(char const* str, unsigned ulength, DuplicationPolicy allocate)
-    : cstr_(str)
-{
+    : cstr_(str) {
   // allocate != duplicate
   storage_.policy_ = allocate & 0x3;
   storage_.length_ = ulength & 0x3FFFFFFF;
@@ -228,15 +227,21 @@ Value::CZString::CZString(char const* str, unsigned ulength, DuplicationPolicy a
 Value::CZString::CZString(const CZString& other)
     : cstr_(other.storage_.policy_ != noDuplication && other.cstr_ != 0
                 ? duplicateStringValue(other.cstr_, other.storage_.length_)
-                : other.cstr_)
-{
+                : other.cstr_) {
   storage_.policy_ = (other.cstr_
                  ? (static_cast<DuplicationPolicy>(other.storage_.policy_) == noDuplication
                      ? noDuplication : duplicate)
                  : static_cast<DuplicationPolicy>(other.storage_.policy_));
   storage_.length_ = other.storage_.length_;
 }
 
+#if JSON_HAS_RVALUE_REFERENCES
+Value::CZString::CZString(CZString&& other)
+  : cstr_(other.cstr_), index_(other.index_) {
+  other.cstr_ = nullptr;
+}
+#endif
+
 Value::CZString::~CZString() {
   if (cstr_ && storage_.policy_ == duplicate)
     releaseStringValue(const_cast<char*>(cstr_));
@@ -425,6 +430,14 @@ Value::Value(Value const& other)
   }
 }
 
+#if JSON_HAS_RVALUE_REFERENCES
+// Move constructor
+Value::Value(Value&& other) {
+  initBasic(nullValue);
+  swap(other);
+}
+#endif
+
 Value::~Value() {
   switch (type_) {
   case nullValue:

src/test_lib_json/main.cpp

@@ -2497,6 +2497,19 @@ JSONTEST_FIXTURE(IteratorTest, const) {
   JSONTEST_ASSERT_STRING_EQUAL(expected, out.str());
 }
 
+struct RValueTest : JsonTest::TestCase {};
+
+JSONTEST_FIXTURE(RValueTest, moveConstruction) {
+#if JSON_HAS_RVALUE_REFERENCES
+  Json::Value json;
+  json["key"] = "value";
+  Json::Value moved = std::move(json);
+  JSONTEST_ASSERT(moved != json); // Possibly not nullValue; definitely not equal.
+  JSONTEST_ASSERT_EQUAL(Json::objectValue, moved.type());
+  JSONTEST_ASSERT_EQUAL(Json::stringValue, moved["key"].type());
+#endif
+}
+
 int main(int argc, const char* argv[]) {
   JsonTest::Runner runner;
   JSONTEST_REGISTER_FIXTURE(runner, ValueTest, checkNormalizeFloatingPointStr);
@@ -2570,5 +2583,7 @@ int main(int argc, const char* argv[]) {
   JSONTEST_REGISTER_FIXTURE(runner, IteratorTest, indexes);
   JSONTEST_REGISTER_FIXTURE(runner, IteratorTest, const);
 
+  JSONTEST_REGISTER_FIXTURE(runner, RValueTest, moveConstruction);
+
   return runner.runCommandLine(argc, argv);
 }