🚧 added fuzzer from OSS-Fuzz

test/fuzz_test/parse_fuzzer.cc

+// Copyright 2016 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <iostream>
+#include <sstream>
+#include <json.hpp>
+
+using json = nlohmann::json;
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  try {
+    std::stringstream s;
+    s << json::parse(data, data + size);
+    try {
+      auto j = json::parse(s.str());
+      std::stringstream s2;
+      s2 << j;
+      assert(s.str() == s2.str());
+      assert(j == json::parse(s.str()));
+    } catch (const std::invalid_argument&) { 
+      assert(0);
+    }
+  } catch (const std::invalid_argument&) { }
+  return 0;
+}