schema's "required" keyword cannot handle duplicated properties

[eyjian]

对于下列代码，Rapidjson Schema不能正常工作。aaa和bbb两者均是required，但document中设置两个aaa，不设bbb，不报错。但如果将其中一个aaa换成其它的，比如注释中的a则会报required错。

#include <rapidjson/document.h>
#include <rapidjson/schema.h>
#include <rapidjson/stringbuffer.h>

int main()
{
        std::string str = "{\"aaa\":111,\"aaa\":222}"; // "\{\"aaa\":111,\"a\":222}"
#if 0
        std::string schema_str = "{\"type\":\"object\",\"properties\":{\"aaa\":{\"type\":\"integer\"},\"bbb\":{\"type\":\"string\"}},\"required\":[\"aaa\",\"bbb\"]}";
#else
        std::string schema_str = "{\"type\":\"object\",\"properties\":{\"aaa\":{\"type\":\"integer\"},\"bbb\":{\"type\":\"integer\"}},\"required\":[\"aaa\",\"bbb\"]}";
#endif
        printf("%s\n", str.c_str());
        printf("%s\n", schema_str.c_str());

        rapidjson::Document doc;
        rapidjson::Document schema_doc;

        schema_doc.Parse(schema_str.c_str());
        doc.Parse(str.c_str());

        rapidjson::SchemaDocument schema(schema_doc);
        rapidjson::SchemaValidator validator(schema);
        if (doc.Accept(validator))
        {
                printf("data ok\n");
        }
        else
        {
                rapidjson::StringBuffer sb;
                validator.GetInvalidSchemaPointer().StringifyUriFragment(sb);

                printf("Invalid schema: %s\n", sb.GetString());
                printf("Invalid keyword: %s\n", validator.GetInvalidSchemaKeyword());

                sb.Clear();
                validator.GetInvalidDocumentPointer().StringifyUriFragment(sb);
                printf("Invalid document: %s\n", sb.GetString());
        }

        return 0;
}