Merge pull request #119 from miloyip/issue116extramemberapi

Three new APIs are added for JSON object type.

include/rapidjson/document.h

@@ -534,9 +534,8 @@ public:
                 break;
 
             case kObjectFlag:
-                for (MemberIterator m = MemberBegin(); m != MemberEnd(); ++m) {
+                for (MemberIterator m = MemberBegin(); m != MemberEnd(); ++m)
                     m->~Member();
-                }
                 Allocator::Free(data_.o.members);
                 break;
 
@@ -745,6 +744,12 @@ public:
     /*! \post IsObject() == true */
     GenericValue& SetObject() { this->~GenericValue(); new (this) GenericValue(kObjectType); return *this; }
 
+    //! Get the number of members in the object.
+    SizeType MemberCount() const { RAPIDJSON_ASSERT(IsObject()); return data_.o.size; }
+
+    //! Check whether the object is empty.
+    bool ObjectEmpty() const { RAPIDJSON_ASSERT(IsObject()); return data_.o.size == 0; }
+
     //! Get the value associated with the name.
     /*!
         \note In version 0.1x, if the member is not found, this function returns a null value. This makes issue 7.
@@ -936,6 +941,17 @@ public:
         return AddMember(n, v, allocator);
     }
 
+    //! Remove all members in the object.
+    /*! This function do not deallocate memory in the object, i.e. the capacity is unchanged.
+        \note Linear time complexity.
+    */
+    void RemoveAllMembers() {
+        RAPIDJSON_ASSERT(IsObject()); 
+        for (MemberIterator m = MemberBegin(); m != MemberEnd(); ++m)
+            m->~Member();
+        data_.o.size = 0;
+    }
+
     //! Remove a member in object by its name.
     /*! \param name Name of member to be removed.
         \return Whether the member existed.

test/unittest/valuetest.cpp

@@ -763,14 +763,21 @@ TEST(Value, Object) {
 
     EXPECT_EQ(kObjectType, x.GetType());
     EXPECT_TRUE(x.IsObject());
+    EXPECT_TRUE(x.ObjectEmpty());
+    EXPECT_EQ(0u, x.MemberCount());
     EXPECT_EQ(kObjectType, y.GetType());
     EXPECT_TRUE(y.IsObject());
+    EXPECT_TRUE(y.ObjectEmpty());
+    EXPECT_EQ(0u, y.MemberCount());
 
     // AddMember()
     x.AddMember("A", "Apple", allocator);
+    EXPECT_FALSE(x.ObjectEmpty());
+    EXPECT_EQ(1u, x.MemberCount());
 
     Value value("Banana", 6);
     x.AddMember("B", "Banana", allocator);
+    EXPECT_EQ(2u, x.MemberCount());
 
     // AddMember<T>(StringRefType, T, Allocator)
     {
@@ -791,6 +798,7 @@ TEST(Value, Object) {
         EXPECT_EQ(INT64_C(-4294967296), o["int64"].GetInt64());
         EXPECT_EQ(UINT64_C(4294967296), o["uint64"].GetUint64());
         EXPECT_STREQ("Jelly",o["string"].GetString());
+        EXPECT_EQ(8u, o.MemberCount());
     }
 
     // Tests a member with null character
@@ -955,6 +963,11 @@ TEST(Value, Object) {
         }
     }
 
+    // RemoveAllMembers()
+    x.RemoveAllMembers();
+    EXPECT_TRUE(x.ObjectEmpty());
+    EXPECT_EQ(0u, x.MemberCount());
+
     // SetObject()
     Value z;
     z.SetObject();