Support JSON output format in addition to XML

This change allows emitting output in JSON format in addition to the
already supported XML format. The implementation as well as the file
structure is intentionally modelled after the XML one.

6 files changed, 1403 insertions, 10 deletions

diff --git a/googletest/CMakeLists.txt b/googletest/CMakeLists.txt
index 77b55cae..575353f4 100644
--- a/googletest/CMakeLists.txt
+++ b/googletest/CMakeLists.txt
@@ -306,7 +306,9 @@ if (gtest_build_tests)
   cxx_executable(gtest_xml_outfile1_test_ test gtest_main)
   cxx_executable(gtest_xml_outfile2_test_ test gtest_main)
   py_test(gtest_xml_outfiles_test)
+  py_test(gtest_json_outfiles_test)
 
   cxx_executable(gtest_xml_output_unittest_ test gtest)
   py_test(gtest_xml_output_unittest)
+  py_test(gtest_json_output_unittest)
 endif()
diff --git a/googletest/docs/AdvancedGuide.md b/googletest/docs/AdvancedGuide.md
index 6605f448..c1a1a4ab 100644
--- a/googletest/docs/AdvancedGuide.md
+++ b/googletest/docs/AdvancedGuide.md
@@ -2060,6 +2060,207 @@ Things to note:
 
 _Availability:_ Linux, Windows, Mac.
 
+#### Generating an JSON Report {#JsonReport}
+
+gUnit can also emit a JSON report as an alternative format to XML. To generate
+the JSON report, set the `GUNIT_OUTPUT` environment variable or the
+`--gunit_output` flag to the string `"json:path_to_output_file"`, which will
+create the file at the given location. You can also just use the string
+`"json"`, in which case the output can be found in the `test_detail.json` file
+in the current directory.
+
+The report format conforms to the following JSON Schema:
+
+```json
+{
+  "$schema": "http://json-schema.org/schema#",
+  "type": "object",
+  "definitions": {
+    "TestCase": {
+      "type": "object",
+      "properties": {
+        "name": { "type": "string" },
+        "tests": { "type": "integer" },
+        "failures": { "type": "integer" },
+        "disabled": { "type": "integer" },
+        "time": { "type": "string" },
+        "testsuite": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/TestInfo"
+          }
+        }
+      }
+    },
+    "TestInfo": {
+      "type": "object",
+      "properties": {
+        "name": { "type": "string" },
+        "status": {
+          "type": "string",
+          "enum": ["RUN", "NOTRUN"]
+        },
+        "time": { "type": "string" },
+        "classname": { "type": "string" },
+        "failures": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/Failure"
+          }
+        }
+      }
+    },
+    "Failure": {
+      "type": "object",
+      "properties": {
+        "failures": { "type": "string" },
+        "type": { "type": "string" }
+      }
+    }
+  },
+  "properties": {
+    "tests": { "type": "integer" },
+    "failures": { "type": "integer" },
+    "disabled": { "type": "integer" },
+    "errors": { "type": "integer" },
+    "timestamp": {
+      "type": "string",
+      "format": "date-time"
+    },
+    "time": { "type": "string" },
+    "name": { "type": "string" },
+    "testsuites": {
+      "type": "array",
+      "items": {
+        "$ref": "#/definitions/TestCase"
+      }
+    }
+  }
+}
+```
+
+The report uses the format that conforms to the following Proto3 using the
+[JSON encoding](https://developers.google.com/protocol-buffers/docs/proto3#json):
+
+```proto
+syntax = "proto3";
+
+package googletest;
+
+import "google/protobuf/timestamp.proto";
+import "google/protobuf/duration.proto";
+
+message UnitTest {
+  int32 tests = 1;
+  int32 failures = 2;
+  int32 disabled = 3;
+  int32 errors = 4;
+  google.protobuf.Timestamp timestamp = 5;
+  google.protobuf.Duration time = 6;
+  string name = 7;
+  repeated TestCase testsuites = 8;
+}
+
+message TestCase {
+  string name = 1;
+  int32 tests = 2;
+  int32 failures = 3;
+  int32 disabled = 4;
+  int32 errors = 5;
+  google.protobuf.Duration time = 6;
+  repeated TestInfo testsuite = 7;
+}
+
+message TestInfo {
+  string name = 1;
+  enum Status {
+    RUN = 0;
+    NOTRUN = 1;
+  }
+  Status status = 2;
+  google.protobuf.Duration time = 3;
+  string classname = 4;
+  message Failure {
+    string failures = 1;
+    string type = 2;
+  }
+  repeated Failure failures = 5;
+}
+```
+
+For instance, the following program
+
+```c++
+TEST(MathTest, Addition) { ... }
+TEST(MathTest, Subtraction) { ... }
+TEST(LogicTest, NonContradiction) { ... }
+```
+
+could generate this report:
+
+```json
+{
+  "tests": 3,
+  "failures": 1,
+  "errors": 0,
+  "time": "0.035s",
+  "timestamp": "2011-10-31T18:52:42Z"
+  "name": "AllTests",
+  "testsuites": [
+    {
+      "name": "MathTest",
+      "tests": 2,
+      "failures": 1,
+      "errors": 0,
+      "time": "0.015s",
+      "testsuite": [
+        {
+          "name": "Addition",
+          "status": "RUN",
+          "time": "0.007s",
+          "classname": "",
+          "failures": [
+            {
+              "message": "Value of: add(1, 1)\x0A  Actual: 3\x0AExpected: 2",
+              "type": ""
+            },
+            {
+              "message": "Value of: add(1, -1)\x0A  Actual: 1\x0AExpected: 0",
+              "type": ""
+            }
+          ]
+        },
+        {
+          "name": "Subtraction",
+          "status": "RUN",
+          "time": "0.005s",
+          "classname": ""
+        }
+      ]
+    }
+    {
+      "name": "LogicTest",
+      "tests": 1,
+      "failures": 0,
+      "errors": 0,
+      "time": "0.005s",
+      "testsuite": [
+        {
+          "name": "NonContradiction",
+          "status": "RUN",
+          "time": "0.005s",
+          "classname": ""
+        }
+      ]
+    }
+  ]
+}
+```
+
+IMPORTANT: The exact format of the JSON document is subject to change.
+
+**Availability**: Linux, Windows, Mac.
+
 ## Controlling How Failures Are Reported ##
 
 ### Turning Assertion Failures into Break-Points ###
diff --git a/googletest/src/gtest.cc b/googletest/src/gtest.cc
index 7afa5a95..15cc9073 100644
--- a/googletest/src/gtest.cc
+++ b/googletest/src/gtest.cc
@@ -160,8 +160,10 @@ static const char kDeathTestCaseFilter[] = "*DeathTest:*DeathTest/*";
 // A test filter that matches everything.
 static const char kUniversalFilter[] = "*";
 
-// The default output file for XML output.
-static const char kDefaultOutputFile[] = "test_detail.xml";
+// The default output format.
+static const char kDefaultOutputFormat[] = "xml";
+// The default output file.
+static const char kDefaultOutputFile[] = "test_detail";
 
 // The environment variable name for the test shard index.
 static const char kTestShardIndex[] = "GTEST_SHARD_INDEX";
@@ -231,9 +233,9 @@ GTEST_DEFINE_bool_(list_tests, false,
 GTEST_DEFINE_string_(
     output,
     internal::StringFromGTestEnv("output", ""),
-    "A format (currently must be \"xml\"), optionally followed "
-    "by a colon and an output file name or directory. A directory "
-    "is indicated by a trailing pathname separator. "
+    "A format (defaults to \"xml\" but can be specified to be \"json\"), "
+    "optionally followed by a colon and an output file name or directory. "
+    "A directory is indicated by a trailing pathname separator. "
     "Examples: \"xml:filename.xml\", \"xml::directoryname/\". "
     "If a directory is specified, output files will be created "
     "within that directory, with file-names based on the test "
@@ -428,12 +430,17 @@ std::string UnitTestOptions::GetAbsolutePathToOutputFile() {
   if (gtest_output_flag == NULL)
     return "";
 
+  std::string format = GetOutputFormat();
+  if (format.empty())
+    format = std::string(kDefaultOutputFormat);
+
   const char* const colon = strchr(gtest_output_flag, ':');
   if (colon == NULL)
-    return internal::FilePath::ConcatPaths(
+    return internal::FilePath::MakeFileName(
         internal::FilePath(
             UnitTest::GetInstance()->original_working_dir()),
-        internal::FilePath(kDefaultOutputFile)).string();
+        internal::FilePath(kDefaultOutputFile), 0,
+        format.c_str()).string();
 
   internal::FilePath output_name(colon + 1);
   if (!output_name.IsAbsolutePath())
@@ -3771,6 +3778,351 @@ std::string XmlUnitTestResultPrinter::TestPropertiesAsXmlAttributes(
 // End XmlUnitTestResultPrinter
 
 
+// This class generates an JSON output file.
+class JsonUnitTestResultPrinter : public EmptyTestEventListener {
+ public:
+  explicit JsonUnitTestResultPrinter(const char* output_file);
+
+  virtual void OnTestIterationEnd(const UnitTest& unit_test, int iteration);
+
+ private:
+  // Returns an JSON-escaped copy of the input string str.
+  static std::string EscapeJson(const std::string& str);
+
+  //// Verifies that the given attribute belongs to the given element and
+  //// streams the attribute as JSON.
+  static void OutputJsonKey(std::ostream* stream,
+                            const std::string& element_name,
+                            const std::string& name,
+                            const std::string& value,
+                            const std::string& indent,
+                            bool comma = true);
+  static void OutputJsonKey(std::ostream* stream,
+                            const std::string& element_name,
+                            const std::string& name,
+                            int value,
+                            const std::string& indent,
+                            bool comma = true);
+
+  // Streams a JSON representation of a TestInfo object.
+  static void OutputJsonTestInfo(::std::ostream* stream,
+                                 const char* test_case_name,
+                                 const TestInfo& test_info);
+
+  // Prints a JSON representation of a TestCase object
+  static void PrintJsonTestCase(::std::ostream* stream,
+                                const TestCase& test_case);
+
+  // Prints a JSON summary of unit_test to output stream out.
+  static void PrintJsonUnitTest(::std::ostream* stream,
+                                const UnitTest& unit_test);
+
+  // Produces a string representing the test properties in a result as
+  // a JSON dictionary.
+  static std::string TestPropertiesAsJson(const TestResult& result,
+                                          const std::string& indent);
+
+  // The output file.
+  const std::string output_file_;
+
+  GTEST_DISALLOW_COPY_AND_ASSIGN_(JsonUnitTestResultPrinter);
+};
+
+// Creates a new JsonUnitTestResultPrinter.
+JsonUnitTestResultPrinter::JsonUnitTestResultPrinter(const char* output_file)
+    : output_file_(output_file) {
+  if (output_file_.empty()) {
+    GTEST_LOG_(FATAL) << "JSON output file may not be null";
+  }
+}
+
+void JsonUnitTestResultPrinter::OnTestIterationEnd(const UnitTest& unit_test,
+                                                  int /*iteration*/) {
+  FILE* jsonout = NULL;
+  FilePath output_file(output_file_);
+  FilePath output_dir(output_file.RemoveFileName());
+
+  if (output_dir.CreateDirectoriesRecursively()) {
+    jsonout = posix::FOpen(output_file_.c_str(), "w");
+  }
+  if (jsonout == NULL) {
+    // TODO(phosek): report the reason of the failure.
+    //
+    // We don't do it for now as:
+    //
+    //   1. There is no urgent need for it.
+    //   2. It's a bit involved to make the errno variable thread-safe on
+    //      all three operating systems (Linux, Windows, and Mac OS).
+    //   3. To interpret the meaning of errno in a thread-safe way,
+    //      we need the strerror_r() function, which is not available on
+    //      Windows.
+    GTEST_LOG_(FATAL) << "Unable to open file \""
+                      << output_file_ << "\"";
+  }
+  std::stringstream stream;
+  PrintJsonUnitTest(&stream, unit_test);
+  fprintf(jsonout, "%s", StringStreamToString(&stream).c_str());
+  fclose(jsonout);
+}
+
+// Returns an JSON-escaped copy of the input string str.
+std::string JsonUnitTestResultPrinter::EscapeJson(const std::string& str) {
+  Message m;
+
+  for (size_t i = 0; i < str.size(); ++i) {
+    const char ch = str[i];
+    switch (ch) {
+      case '\\':
+      case '"':
+      case '/':
+        m << '\\' << ch;
+        break;
+      case '\b':
+        m << "\\b";
+        break;
+      case '\t':
+        m << "\\t";
+        break;
+      case '\n':
+        m << "\\n";
+        break;
+      case '\f':
+        m << "\\f";
+        break;
+      case '\r':
+        m << "\\r";
+        break;
+      default:
+        if (ch < ' ') {
+          m << "\\u00" << String::FormatByte(static_cast<unsigned char>(ch));
+        } else {
+          m << ch;
+        }
+        break;
+    }
+  }
+
+  return m.GetString();
+}
+
+// The following routines generate an JSON representation of a UnitTest
+// object.
+
+// Formats the given time in milliseconds as seconds.
+static std::string FormatTimeInMillisAsDuration(TimeInMillis ms) {
+  ::std::stringstream ss;
+  ss << (static_cast<double>(ms) * 1e-3) << "s";
+  return ss.str();
+}
+
+// Converts the given epoch time in milliseconds to a date string in the
+// RFC3339 format, without the timezone information.
+static std::string FormatEpochTimeInMillisAsRFC3339(TimeInMillis ms) {
+  struct tm time_struct;
+  if (!PortableLocaltime(static_cast<time_t>(ms / 1000), &time_struct))
+    return "";
+  // YYYY-MM-DDThh:mm:ss
+  return StreamableToString(time_struct.tm_year + 1900) + "-" +
+      String::FormatIntWidth2(time_struct.tm_mon + 1) + "-" +
+      String::FormatIntWidth2(time_struct.tm_mday) + "T" +
+      String::FormatIntWidth2(time_struct.tm_hour) + ":" +
+      String::FormatIntWidth2(time_struct.tm_min) + ":" +
+      String::FormatIntWidth2(time_struct.tm_sec) + "Z";
+}
+
+static inline std::string Indent(int width) {
+  return std::string(width, ' ');
+}
+
+void JsonUnitTestResultPrinter::OutputJsonKey(
+    std::ostream* stream,
+    const std::string& element_name,
+    const std::string& name,
+    const std::string& value,
+    const std::string& indent,
+    bool comma) {
+  const std::vector<std::string>& allowed_names =
+      GetReservedAttributesForElement(element_name);
+
+  GTEST_CHECK_(std::find(allowed_names.begin(), allowed_names.end(), name) !=
+                   allowed_names.end())
+      << "Key \"" << name << "\" is not allowed for value \"" << element_name
+      << "\".";
+
+  *stream << indent << "\"" << name << "\": \"" << EscapeJson(value) << "\"";
+  if (comma)
+    *stream << ",\n";
+}
+
+void JsonUnitTestResultPrinter::OutputJsonKey(
+    std::ostream* stream,
+    const std::string& element_name,
+    const std::string& name,
+    int value,
+    const std::string& indent,
+    bool comma) {
+  const std::vector<std::string>& allowed_names =
+      GetReservedAttributesForElement(element_name);
+
+  GTEST_CHECK_(std::find(allowed_names.begin(), allowed_names.end(), name) !=
+                   allowed_names.end())
+      << "Key \"" << name << "\" is not allowed for value \"" << element_name
+      << "\".";
+
+  *stream << indent << "\"" << name << "\": " << StreamableToString(value);
+  if (comma)
+    *stream << ",\n";
+}
+
+// Prints a JSON representation of a TestInfo object.
+void JsonUnitTestResultPrinter::OutputJsonTestInfo(::std::ostream* stream,
+                                                   const char* test_case_name,
+                                                   const TestInfo& test_info) {
+  const TestResult& result = *test_info.result();
+  const std::string kTestcase = "testcase";
+  const std::string kIndent = Indent(10);
+
+  *stream << Indent(8) << "{\n";
+  OutputJsonKey(stream, kTestcase, "name", test_info.name(), kIndent);
+
+  if (test_info.value_param() != NULL) {
+    OutputJsonKey(stream, kTestcase, "value_param",
+                  test_info.value_param(), kIndent);
+  }
+  if (test_info.type_param() != NULL) {
+    OutputJsonKey(stream, kTestcase, "type_param", test_info.type_param(),
+                  kIndent);
+  }
+
+  OutputJsonKey(stream, kTestcase, "status",
+                test_info.should_run() ? "RUN" : "NOTRUN", kIndent);
+  OutputJsonKey(stream, kTestcase, "time",
+                FormatTimeInMillisAsDuration(result.elapsed_time()), kIndent);
+  OutputJsonKey(stream, kTestcase, "classname", test_case_name, kIndent, false);
+  *stream << TestPropertiesAsJson(result, kIndent);
+
+  int failures = 0;
+  for (int i = 0; i < result.total_part_count(); ++i) {
+    const TestPartResult& part = result.GetTestPartResult(i);
+    if (part.failed()) {
+      *stream << ",\n";
+      if (++failures == 1) {
+        *stream << kIndent << "\"" << "failures" << "\": [\n";
+      }
+      const std::string location =
+          internal::FormatCompilerIndependentFileLocation(part.file_name(),
+                                                          part.line_number());
+      const std::string summary = EscapeJson(location + "\n" + part.summary());
+      *stream << kIndent << "  {\n"
+              << kIndent << "    \"failure\": \"" << summary << "\",\n"
+              << kIndent << "    \"type\": \"\"\n"
+              << kIndent << "  }";
+    }
+  }
+
+  if (failures > 0)
+    *stream << "\n" << kIndent << "]";
+  *stream << "\n" << Indent(8) << "}";
+}
+
+// Prints an JSON representation of a TestCase object
+void JsonUnitTestResultPrinter::PrintJsonTestCase(std::ostream* stream,
+                                                  const TestCase& test_case) {
+  const std::string kTestsuite = "testsuite";
+  const std::string kIndent = Indent(6);
+
+  *stream << Indent(4) << "{\n";
+  OutputJsonKey(stream, kTestsuite, "name", test_case.name(), kIndent);
+  OutputJsonKey(stream, kTestsuite, "tests", test_case.reportable_test_count(),
+                kIndent);
+  OutputJsonKey(stream, kTestsuite, "failures", test_case.failed_test_count(),
+                kIndent);
+  OutputJsonKey(stream, kTestsuite, "disabled",
+                test_case.reportable_disabled_test_count(), kIndent);
+  OutputJsonKey(stream, kTestsuite, "errors", 0, kIndent);
+  OutputJsonKey(stream, kTestsuite, "time",
+                FormatTimeInMillisAsDuration(test_case.elapsed_time()), kIndent,
+                false);
+  *stream << TestPropertiesAsJson(test_case.ad_hoc_test_result(), kIndent)
+          << ",\n";
+
+  *stream << kIndent << "\"" << kTestsuite << "\": [\n";
+
+  bool comma = false;
+  for (int i = 0; i < test_case.total_test_count(); ++i) {
+    if (test_case.GetTestInfo(i)->is_reportable()) {
+      if (comma) {
+        *stream << ",\n";
+      } else {
+        comma = true;
+      }
+      OutputJsonTestInfo(stream, test_case.name(), *test_case.GetTestInfo(i));
+    }
+  }
+  *stream << "\n" << kIndent << "]\n" << Indent(4) << "}";
+}
+
+// Prints a JSON summary of unit_test to output stream out.
+void JsonUnitTestResultPrinter::PrintJsonUnitTest(std::ostream* stream,
+                                                  const UnitTest& unit_test) {
+  const std::string kTestsuites = "testsuites";
+  const std::string kIndent = Indent(2);
+  *stream << "{\n";
+
+  OutputJsonKey(stream, kTestsuites, "tests", unit_test.reportable_test_count(),
+                kIndent);
+  OutputJsonKey(stream, kTestsuites, "failures", unit_test.failed_test_count(),
+                kIndent);
+  OutputJsonKey(stream, kTestsuites, "disabled",
+                unit_test.reportable_disabled_test_count(), kIndent);
+  OutputJsonKey(stream, kTestsuites, "errors", 0, kIndent);
+  if (GTEST_FLAG(shuffle)) {
+    OutputJsonKey(stream, kTestsuites, "random_seed", unit_test.random_seed(),
+                  kIndent);
+  }
+  OutputJsonKey(stream, kTestsuites, "timestamp",
+                FormatEpochTimeInMillisAsRFC3339(unit_test.start_timestamp()),
+                kIndent);
+  OutputJsonKey(stream, kTestsuites, "time",
+                FormatTimeInMillisAsDuration(unit_test.elapsed_time()), kIndent,
+                false);
+
+  *stream << TestPropertiesAsJson(unit_test.ad_hoc_test_result(), kIndent)
+          << ",\n";
+
+  OutputJsonKey(stream, kTestsuites, "name", "AllTests", kIndent);
+  *stream << kIndent << "\"" << kTestsuites << "\": [\n";
+
+  bool comma = false;
+  for (int i = 0; i < unit_test.total_test_case_count(); ++i) {
+    if (unit_test.GetTestCase(i)->reportable_test_count() > 0) {
+      if (comma) {
+        *stream << ",\n";
+      } else {
+        comma = true;
+      }
+      PrintJsonTestCase(stream, *unit_test.GetTestCase(i));
+    }
+  }
+
+  *stream << "\n" << kIndent << "]\n" << "}\n";
+}
+
+// Produces a string representing the test properties in a result as
+// a JSON dictionary.
+std::string JsonUnitTestResultPrinter::TestPropertiesAsJson(
+    const TestResult& result, const std::string& indent) {
+  Message attributes;
+  for (int i = 0; i < result.test_property_count(); ++i) {
+    const TestProperty& property = result.GetTestProperty(i);
+    attributes << ",\n" << indent << "\"" << property.key() << "\": "
+               << "\"" << EscapeJson(property.value()) << "\"";
+  }
+  return attributes.GetString();
+}
+
+// End JsonUnitTestResultPrinter
+
 #if GTEST_CAN_STREAM_RESULTS_
 
 // Checks if str contains '=', '&', '%' or '\n' characters. If yes,
@@ -4397,6 +4749,9 @@ void UnitTestImpl::ConfigureXmlOutput() {
   if (output_format == "xml") {
     listeners()->SetDefaultXmlGenerator(new XmlUnitTestResultPrinter(
         UnitTestOptions::GetAbsolutePathToOutputFile().c_str()));
+  } else if (output_format == "json") {
+    listeners()->SetDefaultXmlGenerator(new JsonUnitTestResultPrinter(
+        UnitTestOptions::GetAbsolutePathToOutputFile().c_str()));
   } else if (output_format != "") {
     GTEST_LOG_(WARNING) << "WARNING: unrecognized output format \""
                         << output_format << "\" ignored.";
@@ -5182,10 +5537,10 @@ static const char kColorEncodedHelpMessage[] =
 "      Enable/disable colored output. The default is @Gauto@D.\n"
 "  @G--" GTEST_FLAG_PREFIX_ "print_time=0@D\n"
 "      Don't print the elapsed time of each test.\n"
-"  @G--" GTEST_FLAG_PREFIX_ "output=xml@Y[@G:@YDIRECTORY_PATH@G"
+"  @G--" GTEST_FLAG_PREFIX_ "output=@Y(@Gjson@Y|@Gxml@Y)[@G:@YDIRECTORY_PATH@G"
     GTEST_PATH_SEP_ "@Y|@G:@YFILE_PATH]@D\n"
-"      Generate an XML report in the given directory or with the given file\n"
-"      name. @YFILE_PATH@D defaults to @Gtest_detail.xml@D.\n"
+"      Generate a JSON or XML report in the given directory or with the given\n"
+"      file name. @YFILE_PATH@D defaults to @Gtest_details.xml@D.\n"
 #if GTEST_CAN_STREAM_RESULTS_
 "  @G--" GTEST_FLAG_PREFIX_ "stream_result_to=@YHOST@G:@YPORT@D\n"
 "      Stream test results to the given server.\n"
diff --git a/googletest/test/gtest_json_outfiles_test.py b/googletest/test/gtest_json_outfiles_test.py
new file mode 100644
index 00000000..62ad18e7
--- /dev/null
+++ b/googletest/test/gtest_json_outfiles_test.py
@@ -0,0 +1,163 @@
+#!/usr/bin/env python
+# Copyright 2018, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Unit test for the gtest_json_output module."""
+
+import json
+import os
+import gtest_test_utils
+import gtest_json_test_utils
+
+
+GTEST_OUTPUT_SUBDIR = 'json_outfiles'
+GTEST_OUTPUT_1_TEST = 'gtest_xml_outfile1_test_'
+GTEST_OUTPUT_2_TEST = 'gtest_xml_outfile2_test_'
+
+EXPECTED_1 = {
+    u'tests': 1,
+    u'failures': 0,
+    u'disabled': 0,
+    u'errors': 0,
+    u'time': u'*',
+    u'timestamp': u'*',
+    u'name': u'AllTests',
+    u'testsuites': [{
+        u'name': u'PropertyOne',
+        u'tests': 1,
+        u'failures': 0,
+        u'disabled': 0,
+        u'errors': 0,
+        u'time': u'*',
+        u'testsuite': [{
+            u'name': u'TestSomeProperties',
+            u'status': u'RUN',
+            u'time': u'*',
+            u'classname': u'PropertyOne',
+            u'SetUpProp': u'1',
+            u'TestSomeProperty': u'1',
+            u'TearDownProp': u'1',
+        }],
+    }],
+}
+
+EXPECTED_2 = {
+    u'tests': 1,
+    u'failures': 0,
+    u'disabled': 0,
+    u'errors': 0,
+    u'time': u'*',
+    u'timestamp': u'*',
+    u'name': u'AllTests',
+    u'testsuites': [{
+        u'name': u'PropertyTwo',
+        u'tests': 1,
+        u'failures': 0,
+        u'disabled': 0,
+        u'errors': 0,
+        u'time': u'*',
+        u'testsuite': [{
+            u'name': u'TestSomeProperties',
+            u'status': u'RUN',
+            u'time': u'*',
+            u'classname': u'PropertyTwo',
+            u'SetUpProp': u'2',
+            u'TestSomeProperty': u'2',
+            u'TearDownProp': u'2',
+        }],
+    }],
+}
+
+
+class GTestJsonOutFilesTest(gtest_test_utils.TestCase):
+  """Unit test for Google Test's JSON output functionality."""
+
+  def setUp(self):
+    # We want the trailing '/' that the last "" provides in os.path.join, for
+    # telling Google Test to create an output directory instead of a single file
+    # for xml output.
+    self.output_dir_ = os.path.join(gtest_test_utils.GetTempDir(),
+                                    GTEST_OUTPUT_SUBDIR, '')
+    self.DeleteFilesAndDir()
+
+  def tearDown(self):
+    self.DeleteFilesAndDir()
+
+  def DeleteFilesAndDir(self):
+    try:
+      os.remove(os.path.join(self.output_dir_, GTEST_OUTPUT_1_TEST + '.json'))
+    except os.error:
+      pass
+    try:
+      os.remove(os.path.join(self.output_dir_, GTEST_OUTPUT_2_TEST + '.json'))
+    except os.error:
+      pass
+    try:
+      os.rmdir(self.output_dir_)
+    except os.error:
+      pass
+
+  def testOutfile1(self):
+    self._TestOutFile(GTEST_OUTPUT_1_TEST, EXPECTED_1)
+
+  def testOutfile2(self):
+    self._TestOutFile(GTEST_OUTPUT_2_TEST, EXPECTED_2)
+
+  def _TestOutFile(self, test_name, expected):
+    gtest_prog_path = gtest_test_utils.GetTestExecutablePath(test_name)
+    command = [gtest_prog_path, '--gtest_output=json:%s' % self.output_dir_]
+    p = gtest_test_utils.Subprocess(command,
+                                    working_dir=gtest_test_utils.GetTempDir())
+    self.assert_(p.exited)
+    self.assertEquals(0, p.exit_code)
+
+    # TODO(wan@google.com): libtool causes the built test binary to be
+    #   named lt-gtest_xml_outfiles_test_ instead of
+    #   gtest_xml_outfiles_test_.  To account for this possibility, we
+    #   allow both names in the following code.  We should remove this
+    #   hack when Chandler Carruth's libtool replacement tool is ready.
+    output_file_name1 = test_name + '.json'
+    output_file1 = os.path.join(self.output_dir_, output_file_name1)
+    output_file_name2 = 'lt-' + output_file_name1
+    output_file2 = os.path.join(self.output_dir_, output_file_name2)
+    self.assert_(os.path.isfile(output_file1) or os.path.isfile(output_file2),
+                 output_file1)
+
+    if os.path.isfile(output_file1):
+      with open(output_file1) as f:
+        actual = json.load(f)
+    else:
+      with open(output_file2) as f:
+        actual = json.load(f)
+    self.assertEqual(expected, gtest_json_test_utils.normalize(actual))
+
+
+if __name__ == '__main__':
+  os.environ['GTEST_STACK_TRACE_DEPTH'] = '0'
+  gtest_test_utils.Main()
diff --git a/googletest/test/gtest_json_output_unittest.py b/googletest/test/gtest_json_output_unittest.py
new file mode 100644
index 00000000..4d23c3ab
--- /dev/null
+++ b/googletest/test/gtest_json_output_unittest.py
@@ -0,0 +1,612 @@
+#!/usr/bin/env python
+# Copyright 2018, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Unit test for the gtest_json_output module."""
+
+import datetime
+import errno
+import json
+import os
+import re
+import sys
+
+import gtest_test_utils
+import gtest_json_test_utils
+
+
+GTEST_FILTER_FLAG = '--gtest_filter'
+GTEST_LIST_TESTS_FLAG = '--gtest_list_tests'
+GTEST_OUTPUT_FLAG = '--gtest_output'
+GTEST_DEFAULT_OUTPUT_FILE = 'test_detail.json'
+GTEST_PROGRAM_NAME = 'gtest_xml_output_unittest_'
+
+SUPPORTS_STACK_TRACES = False
+
+if SUPPORTS_STACK_TRACES:
+  STACK_TRACE_TEMPLATE = '\nStack trace:\n*'
+else:
+  STACK_TRACE_TEMPLATE = ''
+
+EXPECTED_NON_EMPTY = {
+    u'tests': 23,
+    u'failures': 4,
+    u'disabled': 2,
+    u'errors': 0,
+    u'timestamp': u'*',
+    u'time': u'*',
+    u'ad_hoc_property': u'42',
+    u'name': u'AllTests',
+    u'testsuites': [
+        {
+            u'name': u'SuccessfulTest',
+            u'tests': 1,
+            u'failures': 0,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'Succeeds',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'SuccessfulTest'
+                }
+            ]
+        },
+        {
+            u'name': u'FailedTest',
+            u'tests': 1,
+            u'failures': 1,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'Fails',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'FailedTest',
+                    u'failures': [
+                        {
+                            u'failure':
+                                u'gtest_xml_output_unittest_.cc:*\n'
+                                u'Expected equality of these values:\n'
+                                u'  1\n  2' + STACK_TRACE_TEMPLATE,
+                            u'type': u''
+                        }
+                    ]
+                }
+            ]
+        },
+        {
+            u'name': u'DisabledTest',
+            u'tests': 1,
+            u'failures': 0,
+            u'disabled': 1,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'DISABLED_test_not_run',
+                    u'status': u'NOTRUN',
+                    u'time': u'*',
+                    u'classname': u'DisabledTest'
+                }
+            ]
+        },
+        {
+            u'name': u'MixedResultTest',
+            u'tests': 3,
+            u'failures': 1,
+            u'disabled': 1,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'Succeeds',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'MixedResultTest'
+                },
+                {
+                    u'name': u'Fails',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'MixedResultTest',
+                    u'failures': [
+                        {
+                            u'failure':
+                                u'gtest_xml_output_unittest_.cc:*\n'
+                                u'Expected equality of these values:\n'
+                                u'  1\n  2' + STACK_TRACE_TEMPLATE,
+                            u'type': u''
+                        },
+                        {
+                            u'failure':
+                                u'gtest_xml_output_unittest_.cc:*\n'
+                                u'Expected equality of these values:\n'
+                                u'  2\n  3' + STACK_TRACE_TEMPLATE,
+                            u'type': u''
+                        }
+                    ]
+                },
+                {
+                    u'name': u'DISABLED_test',
+                    u'status': u'NOTRUN',
+                    u'time': u'*',
+                    u'classname': u'MixedResultTest'
+                }
+            ]
+        },
+        {
+            u'name': u'XmlQuotingTest',
+            u'tests': 1,
+            u'failures': 1,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'OutputsCData',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'XmlQuotingTest',
+                    u'failures': [
+                        {
+                            u'failure':
+                                u'gtest_xml_output_unittest_.cc:*\n'
+                                u'Failed\nXML output: <?xml encoding="utf-8">'
+                                u'<top><![CDATA[cdata text]]></top>' +
+                                STACK_TRACE_TEMPLATE,
+                            u'type': u''
+                        }
+                    ]
+                }
+            ]
+        },
+        {
+            u'name': u'InvalidCharactersTest',
+            u'tests': 1,
+            u'failures': 1,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'InvalidCharactersInMessage',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'InvalidCharactersTest',
+                    u'failures': [
+                        {
+                            u'failure':
+                                u'gtest_xml_output_unittest_.cc:*\n'
+                                u'Failed\nInvalid characters in brackets'
+                                u' [\x01\x02]' + STACK_TRACE_TEMPLATE,
+                            u'type': u''
+                        }
+                    ]
+                }
+            ]
+        },
+        {
+            u'name': u'PropertyRecordingTest',
+            u'tests': 4,
+            u'failures': 0,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'SetUpTestCase': u'yes',
+            u'TearDownTestCase': u'aye',
+            u'testsuite': [
+                {
+                    u'name': u'OneProperty',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'PropertyRecordingTest',
+                    u'key_1': u'1'
+                },
+                {
+                    u'name': u'IntValuedProperty',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'PropertyRecordingTest',
+                    u'key_int': u'1'
+                },
+                {
+                    u'name': u'ThreeProperties',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'PropertyRecordingTest',
+                    u'key_1': u'1',
+                    u'key_2': u'2',
+                    u'key_3': u'3'
+                },
+                {
+                    u'name': u'TwoValuesForOneKeyUsesLastValue',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'PropertyRecordingTest',
+                    u'key_1': u'2'
+                }
+            ]
+        },
+        {
+            u'name': u'NoFixtureTest',
+            u'tests': 3,
+            u'failures': 0,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'RecordProperty',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'NoFixtureTest',
+                    u'key': u'1'
+                },
+                {
+                    u'name': u'ExternalUtilityThatCallsRecordIntValuedProperty',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'NoFixtureTest',
+                    u'key_for_utility_int': u'1'
+                },
+                {
+                    u'name':
+                        u'ExternalUtilityThatCallsRecordStringValuedProperty',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'NoFixtureTest',
+                    u'key_for_utility_string': u'1'
+                }
+            ]
+        },
+        {
+            u'name': u'TypedTest/0',
+            u'tests': 1,
+            u'failures': 0,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'HasTypeParamAttribute',
+                    u'type_param': u'int',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'TypedTest/0'
+                }
+            ]
+        },
+        {
+            u'name': u'TypedTest/1',
+            u'tests': 1,
+            u'failures': 0,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'HasTypeParamAttribute',
+                    u'type_param': u'long',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'TypedTest/1'
+                }
+            ]
+        },
+        {
+            u'name': u'Single/TypeParameterizedTestCase/0',
+            u'tests': 1,
+            u'failures': 0,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'HasTypeParamAttribute',
+                    u'type_param': u'int',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'Single/TypeParameterizedTestCase/0'
+                }
+            ]
+        },
+        {
+            u'name': u'Single/TypeParameterizedTestCase/1',
+            u'tests': 1,
+            u'failures': 0,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'HasTypeParamAttribute',
+                    u'type_param': u'long',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'Single/TypeParameterizedTestCase/1'
+                }
+            ]
+        },
+        {
+            u'name': u'Single/ValueParamTest',
+            u'tests': 4,
+            u'failures': 0,
+            u'disabled': 0,
+            u'errors': 0,
+            u'time': u'*',
+            u'testsuite': [
+                {
+                    u'name': u'HasValueParamAttribute/0',
+                    u'value_param': u'33',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'Single/ValueParamTest'
+                },
+                {
+                    u'name': u'HasValueParamAttribute/1',
+                    u'value_param': u'42',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'Single/ValueParamTest'
+                },
+                {
+                    u'name': u'AnotherTestThatHasValueParamAttribute/0',
+                    u'value_param': u'33',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'Single/ValueParamTest'
+                },
+                {
+                    u'name': u'AnotherTestThatHasValueParamAttribute/1',
+                    u'value_param': u'42',
+                    u'status': u'RUN',
+                    u'time': u'*',
+                    u'classname': u'Single/ValueParamTest'
+                }
+            ]
+        }
+    ]
+}
+
+EXPECTED_FILTERED = {
+    u'tests': 1,
+    u'failures': 0,
+    u'disabled': 0,
+    u'errors': 0,
+    u'time': u'*',
+    u'timestamp': u'*',
+    u'name': u'AllTests',
+    u'ad_hoc_property': u'42',
+    u'testsuites': [{
+        u'name': u'SuccessfulTest',
+        u'tests': 1,
+        u'failures': 0,
+        u'disabled': 0,
+        u'errors': 0,
+        u'time': u'*',
+        u'testsuite': [{
+            u'name': u'Succeeds',
+            u'status': u'RUN',
+            u'time': u'*',
+            u'classname': u'SuccessfulTest',
+        }]
+    }],
+}
+
+EXPECTED_EMPTY = {
+    u'tests': 0,
+    u'failures': 0,
+    u'disabled': 0,
+    u'errors': 0,
+    u'time': u'*',
+    u'timestamp': u'*',
+    u'name': u'AllTests',
+    u'testsuites': [],
+}
+
+GTEST_PROGRAM_PATH = gtest_test_utils.GetTestExecutablePath(GTEST_PROGRAM_NAME)
+
+SUPPORTS_TYPED_TESTS = 'TypedTest' in gtest_test_utils.Subprocess(
+    [GTEST_PROGRAM_PATH, GTEST_LIST_TESTS_FLAG], capture_stderr=False).output
+
+
+class GTestJsonOutputUnitTest(gtest_test_utils.TestCase):
+  """Unit test for Google Test's JSON output functionality.
+  """
+
+  # This test currently breaks on platforms that do not support typed and
+  # type-parameterized tests, so we don't run it under them.
+  if SUPPORTS_TYPED_TESTS:
+
+    def testNonEmptyJsonOutput(self):
+      """Verifies JSON output for a Google Test binary with non-empty output.
+
+      Runs a test program that generates a non-empty JSON output, and
+      tests that the JSON output is expected.
+      """
+      self._TestJsonOutput(GTEST_PROGRAM_NAME, EXPECTED_NON_EMPTY, 1)
+
+  def testEmptyJsonOutput(self):
+    """Verifies JSON output for a Google Test binary without actual tests.
+
+    Runs a test program that generates an empty JSON output, and
+    tests that the JSON output is expected.
+    """
+
+    self._TestJsonOutput('gtest_no_test_unittest', EXPECTED_EMPTY, 0)
+
+  def testTimestampValue(self):
+    """Checks whether the timestamp attribute in the JSON output is valid.
+
+    Runs a test program that generates an empty JSON output, and checks if
+    the timestamp attribute in the testsuites tag is valid.
+    """
+    actual = self._GetJsonOutput('gtest_no_test_unittest', [], 0)
+    date_time_str = actual['timestamp']
+    # datetime.strptime() is only available in Python 2.5+ so we have to
+    # parse the expected datetime manually.
+    match = re.match(r'(\d+)-(\d\d)-(\d\d)T(\d\d):(\d\d):(\d\d)', date_time_str)
+    self.assertTrue(
+        re.match,
+        'JSON datettime string %s has incorrect format' % date_time_str)
+    date_time_from_json = datetime.datetime(
+        year=int(match.group(1)), month=int(match.group(2)),
+        day=int(match.group(3)), hour=int(match.group(4)),
+        minute=int(match.group(5)), second=int(match.group(6)))
+
+    time_delta = abs(datetime.datetime.now() - date_time_from_json)
+    # timestamp value should be near the current local time
+    self.assertTrue(time_delta < datetime.timedelta(seconds=600),
+                    'time_delta is %s' % time_delta)
+
+  def testDefaultOutputFile(self):
+    """Verifies the default output file name.
+
+    Confirms that Google Test produces an JSON output file with the expected
+    default name if no name is explicitly specified.
+    """
+    output_file = os.path.join(gtest_test_utils.GetTempDir(),
+                               GTEST_DEFAULT_OUTPUT_FILE)
+    gtest_prog_path = gtest_test_utils.GetTestExecutablePath(
+        'gtest_no_test_unittest')
+    try:
+      os.remove(output_file)
+    except OSError:
+      e = sys.exc_info()[1]
+      if e.errno != errno.ENOENT:
+        raise
+
+    p = gtest_test_utils.Subprocess(
+        [gtest_prog_path, '%s=json' % GTEST_OUTPUT_FLAG],
+        working_dir=gtest_test_utils.GetTempDir())
+    self.assert_(p.exited)
+    self.assertEquals(0, p.exit_code)
+    self.assert_(os.path.isfile(output_file))
+
+  def testSuppressedJsonOutput(self):
+    """Verifies that no JSON output is generated.
+
+    Tests that no JSON file is generated if the default JSON listener is
+    shut down before RUN_ALL_TESTS is invoked.
+    """
+
+    json_path = os.path.join(gtest_test_utils.GetTempDir(),
+                             GTEST_PROGRAM_NAME + 'out.json')
+    if os.path.isfile(json_path):
+      os.remove(json_path)
+
+    command = [GTEST_PROGRAM_PATH,
+               '%s=json:%s' % (GTEST_OUTPUT_FLAG, json_path),
+               '--shut_down_xml']
+    p = gtest_test_utils.Subprocess(command)
+    if p.terminated_by_signal:
+      # p.signal is available only if p.terminated_by_signal is True.
+      self.assertFalse(
+          p.terminated_by_signal,
+          '%s was killed by signal %d' % (GTEST_PROGRAM_NAME, p.signal))
+    else:
+      self.assert_(p.exited)
+      self.assertEquals(1, p.exit_code,
+                        "'%s' exited with code %s, which doesn't match "
+                        'the expected exit code %s.'
+                        % (command, p.exit_code, 1))
+
+    self.assert_(not os.path.isfile(json_path))
+
+  def testFilteredTestJsonOutput(self):
+    """Verifies JSON output when a filter is applied.
+
+    Runs a test program that executes only some tests and verifies that
+    non-selected tests do not show up in the JSON output.
+    """
+
+    self._TestJsonOutput(GTEST_PROGRAM_NAME, EXPECTED_FILTERED, 0,
+                         extra_args=['%s=SuccessfulTest.*' % GTEST_FILTER_FLAG])
+
+  def _GetJsonOutput(self, gtest_prog_name, extra_args, expected_exit_code):
+    """Returns the JSON output generated by running the program gtest_prog_name.
+
+    Furthermore, the program's exit code must be expected_exit_code.
+
+    Args:
+      gtest_prog_name: Google Test binary name.
+      extra_args: extra arguments to binary invocation.
+      expected_exit_code: program's exit code.
+    """
+    json_path = os.path.join(gtest_test_utils.GetTempDir(),
+                             gtest_prog_name + 'out.json')
+    gtest_prog_path = gtest_test_utils.GetTestExecutablePath(gtest_prog_name)
+
+    command = (
+        [gtest_prog_path, '%s=json:%s' % (GTEST_OUTPUT_FLAG, json_path)] +
+        extra_args
+    )
+    p = gtest_test_utils.Subprocess(command)
+    if p.terminated_by_signal:
+      self.assert_(False,
+                   '%s was killed by signal %d' % (gtest_prog_name, p.signal))
+    else:
+      self.assert_(p.exited)
+      self.assertEquals(expected_exit_code, p.exit_code,
+                        "'%s' exited with code %s, which doesn't match "
+                        'the expected exit code %s.'
+                        % (command, p.exit_code, expected_exit_code))
+    with open(json_path) as f:
+      actual = json.load(f)
+    return actual
+
+  def _TestJsonOutput(self, gtest_prog_name, expected,
+                      expected_exit_code, extra_args=None):
+    """Checks the JSON output generated by the Google Test binary.
+
+    Asserts that the JSON document generated by running the program
+    gtest_prog_name matches expected_json, a string containing another
+    JSON document.  Furthermore, the program's exit code must be
+    expected_exit_code.
+
+    Args:
+      gtest_prog_name: Google Test binary name.
+      expected: expected output.
+      expected_exit_code: program's exit code.
+      extra_args: extra arguments to binary invocation.
+    """
+
+    actual = self._GetJsonOutput(gtest_prog_name, extra_args or [],
+                                 expected_exit_code)
+    self.assertEqual(expected, gtest_json_test_utils.normalize(actual))
+
+
+if __name__ == '__main__':
+  os.environ['GTEST_STACK_TRACE_DEPTH'] = '1'
+  gtest_test_utils.Main()
diff --git a/googletest/test/gtest_json_test_utils.py b/googletest/test/gtest_json_test_utils.py
new file mode 100644
index 00000000..4ef5f6fc
--- /dev/null
+++ b/googletest/test/gtest_json_test_utils.py
@@ -0,0 +1,60 @@
+# Copyright 2018, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Unit test utilities for gtest_json_output."""
+
+import re
+
+
+def normalize(obj):
+  """Normalize output object.
+
+  Args:
+     obj: Google Test's JSON output object to normalize.
+
+  Returns:
+     Normalized output without any references to transient information that may
+     change from run to run.
+  """
+  def _normalize(key, value):
+    if key == 'time':
+      return re.sub(r'^\d+(\.\d+)?s$', u'*', value)
+    elif key == 'timestamp':
+      return re.sub(r'^\d{4}-\d\d-\d\dT\d\d:\d\d:\d\dZ$', '*', value)
+    elif key == 'failure':
+      value = re.sub(r'^.*[/\\](.*:)\d+\n', '\\1*\n', value)
+      return re.sub(r'Stack trace:\n(.|\n)*', 'Stack trace:\n*', value)
+    else:
+      return normalize(value)
+  if isinstance(obj, dict):
+    return {k: _normalize(k, v) for k, v in obj.items()}
+  if isinstance(obj, list):
+    return [normalize(x) for x in obj]
+  else:
+    return obj