Add JSON reporter (#2706)

Co-authored-by: Martin Hořeňovský <martin.horenovsky@gmail.com>

19 files changed, 1737 insertions, 19 deletions

diff --git a/tests/SelfTest/Baselines/automake.sw.approved.txt b/tests/SelfTest/Baselines/automake.sw.approved.txt
index 6748c0ec..0f029e6d 100644
--- a/tests/SelfTest/Baselines/automake.sw.approved.txt
+++ b/tests/SelfTest/Baselines/automake.sw.approved.txt
@@ -170,6 +170,7 @@ Nor would this
 :test-result: XFAIL Incomplete AssertionHandler
 :test-result: XFAIL Inequality checks that should fail
 :test-result: PASS Inequality checks that should succeed
+:test-result: PASS JsonWriter
 :test-result: PASS Lambdas in assertions
 :test-result: PASS Less-than inequalities with different epsilons
 :test-result: PASS ManuallyRegistered
diff --git a/tests/SelfTest/Baselines/automake.sw.multi.approved.txt b/tests/SelfTest/Baselines/automake.sw.multi.approved.txt
index a8bdcfa1..a3af0658 100644
--- a/tests/SelfTest/Baselines/automake.sw.multi.approved.txt
+++ b/tests/SelfTest/Baselines/automake.sw.multi.approved.txt
@@ -168,6 +168,7 @@
 :test-result: XFAIL Incomplete AssertionHandler
 :test-result: XFAIL Inequality checks that should fail
 :test-result: PASS Inequality checks that should succeed
+:test-result: PASS JsonWriter
 :test-result: PASS Lambdas in assertions
 :test-result: PASS Less-than inequalities with different epsilons
 :test-result: PASS ManuallyRegistered
diff --git a/tests/SelfTest/Baselines/compact.sw.approved.txt b/tests/SelfTest/Baselines/compact.sw.approved.txt
index dafa08db..e78c989f 100644
--- a/tests/SelfTest/Baselines/compact.sw.approved.txt
+++ b/tests/SelfTest/Baselines/compact.sw.approved.txt
@@ -979,6 +979,83 @@ Condition.tests.cpp:<line number>: passed: data.str_hello != "goodbye" for: "hel
 Condition.tests.cpp:<line number>: passed: data.str_hello != "hell" for: "hello" != "hell"
 Condition.tests.cpp:<line number>: passed: data.str_hello != "hello1" for: "hello" != "hello1"
 Condition.tests.cpp:<line number>: passed: data.str_hello.size() != 6 for: 5 != 6
+Json.tests.cpp:<line number>: passed: stream.str() == "" for: "" == ""
+Json.tests.cpp:<line number>: passed: stream.str() == "{\n}" for: "{
+}"
+==
+"{
+}"
+Json.tests.cpp:<line number>: passed: stream.str(), ContainsSubstring( "\"int\": 1," ) && ContainsSubstring( "\"double\": 1.5," ) && ContainsSubstring( "\"true\": true," ) && ContainsSubstring( "\"false\": false," ) && ContainsSubstring( "\"string\": \"this is a string\"," ) && ContainsSubstring( "\"array\": [\n    1,\n    2\n  ]\n}" ) for: "{
+  "int": 1,
+  "double": 1.5,
+  "true": true,
+  "false": false,
+  "string": "this is a string",
+  "array": [
+    1,
+    2
+  ]
+}" ( contains: ""int": 1," and contains: ""double": 1.5," and contains: ""true": true," and contains: ""false": false," and contains: ""string": "this is a string"," and contains: ""array": [
+    1,
+    2
+  ]
+}" )
+Json.tests.cpp:<line number>: passed: stream.str(), ContainsSubstring( "\"empty_object\": {\n  }," ) && ContainsSubstring( "\"fully_object\": {\n    \"key\": 1\n  }" ) for: "{
+  "empty_object": {
+  },
+  "fully_object": {
+    "key": 1
+  }
+}" ( contains: ""empty_object": {
+  }," and contains: ""fully_object": {
+    "key": 1
+  }" )
+Json.tests.cpp:<line number>: passed: stream.str() == "[\n]" for: "[
+]"
+==
+"[
+]"
+Json.tests.cpp:<line number>: passed: stream.str() == "[\n  1,\n  1.5,\n  true,\n  false,\n  \"this is a string\",\n  {\n    \"object\": 42\n  },\n  [\n    \"array\",\n    42.5\n  ]\n]" for: "[
+  1,
+  1.5,
+  true,
+  false,
+  "this is a string",
+  {
+    "object": 42
+  },
+  [
+    "array",
+    42.5
+  ]
+]"
+==
+"[
+  1,
+  1.5,
+  true,
+  false,
+  "this is a string",
+  {
+    "object": 42
+  },
+  [
+    "array",
+    42.5
+  ]
+]"
+Json.tests.cpp:<line number>: passed: stream.str() == "{\n}" for: "{
+}"
+==
+"{
+}"
+Json.tests.cpp:<line number>: passed: stream.str() == "[\n]" for: "[
+]"
+==
+"[
+]"
+Json.tests.cpp:<line number>: passed: stream.str() == "\"custom\"" for: ""custom"" == ""custom""
+Json.tests.cpp:<line number>: passed: stream.str() == "\"\\\"\"" for: ""\""" == ""\"""
 Compilation.tests.cpp:<line number>: passed: []() { return true; }() for: true
 Approx.tests.cpp:<line number>: passed: d <= Approx( 1.24 ) for: 1.23 <= Approx( 1.24 )
 Approx.tests.cpp:<line number>: passed: d <= Approx( 1.23 ) for: 1.23 <= Approx( 1.23 )
@@ -1343,6 +1420,60 @@ Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring( "fa
 
 " ( contains: "fake test name" and contains: "fakeTestTag" ) with 1 message: 'Tested reporter: console'
 Reporters.tests.cpp:<line number>: passed: !(factories.empty()) for: !false
+Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring("fakeTag"s) for: "{
+  "version": 1,
+  "metadata": {
+    "name": "",
+    "rng-seed": 1234,
+    "catch2-version": "<version>"
+  },
+  "listings": {
+    "tags": [
+      {
+        "aliases": [
+          "fakeTag"
+        ],
+        "count": 1
+      }
+    ]" contains: "fakeTag" with 1 message: 'Tested reporter: JSON'
+Reporters.tests.cpp:<line number>: passed: !(factories.empty()) for: !false
+Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring("fake reporter"s) for: "{
+  "version": 1,
+  "metadata": {
+    "name": "",
+    "rng-seed": 1234,
+    "catch2-version": "<version>"
+  },
+  "listings": {
+    "reporters": [
+      {
+        "name": "fake reporter",
+        "description": "fake description"
+      }
+    ]" contains: "fake reporter" with 1 message: 'Tested reporter: JSON'
+Reporters.tests.cpp:<line number>: passed: !(factories.empty()) for: !false
+Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring( "fake test name"s ) && ContainsSubstring( "fakeTestTag"s ) for: "{
+  "version": 1,
+  "metadata": {
+    "name": "",
+    "rng-seed": 1234,
+    "catch2-version": "<version>"
+  },
+  "listings": {
+    "tests": [
+      {
+        "name": "fake test name",
+        "class-name": "",
+        "tags": [
+          "fakeTestTag"
+        ],
+        "source-location": {
+          "filename": "fake-file.cpp",
+          "line": 123456789
+        }
+      }
+    ]" ( contains: "fake test name" and contains: "fakeTestTag" ) with 1 message: 'Tested reporter: JSON'
+Reporters.tests.cpp:<line number>: passed: !(factories.empty()) for: !false
 Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring("fakeTag"s) for: "<?xml version="1.0" encoding="UTF-8"?>
 All available tags:
    1  [fakeTag]
@@ -2544,7 +2675,7 @@ InternalBenchmark.tests.cpp:<line number>: passed: med == 18. for: 18.0 == 18.0
 InternalBenchmark.tests.cpp:<line number>: passed: q3 == 23. for: 23.0 == 23.0
 Misc.tests.cpp:<line number>: passed:
 Misc.tests.cpp:<line number>: passed:
-test cases:  413 |  308 passed |  85 failed | 6 skipped | 14 failed as expected
-assertions: 2230 | 2049 passed | 146 failed | 35 failed as expected
+test cases:  414 |  309 passed |  85 failed | 6 skipped | 14 failed as expected
+assertions: 2246 | 2065 passed | 146 failed | 35 failed as expected
 
 
diff --git a/tests/SelfTest/Baselines/compact.sw.multi.approved.txt b/tests/SelfTest/Baselines/compact.sw.multi.approved.txt
index 36debdb7..8f177e46 100644
--- a/tests/SelfTest/Baselines/compact.sw.multi.approved.txt
+++ b/tests/SelfTest/Baselines/compact.sw.multi.approved.txt
@@ -977,6 +977,83 @@ Condition.tests.cpp:<line number>: passed: data.str_hello != "goodbye" for: "hel
 Condition.tests.cpp:<line number>: passed: data.str_hello != "hell" for: "hello" != "hell"
 Condition.tests.cpp:<line number>: passed: data.str_hello != "hello1" for: "hello" != "hello1"
 Condition.tests.cpp:<line number>: passed: data.str_hello.size() != 6 for: 5 != 6
+Json.tests.cpp:<line number>: passed: stream.str() == "" for: "" == ""
+Json.tests.cpp:<line number>: passed: stream.str() == "{\n}" for: "{
+}"
+==
+"{
+}"
+Json.tests.cpp:<line number>: passed: stream.str(), ContainsSubstring( "\"int\": 1," ) && ContainsSubstring( "\"double\": 1.5," ) && ContainsSubstring( "\"true\": true," ) && ContainsSubstring( "\"false\": false," ) && ContainsSubstring( "\"string\": \"this is a string\"," ) && ContainsSubstring( "\"array\": [\n    1,\n    2\n  ]\n}" ) for: "{
+  "int": 1,
+  "double": 1.5,
+  "true": true,
+  "false": false,
+  "string": "this is a string",
+  "array": [
+    1,
+    2
+  ]
+}" ( contains: ""int": 1," and contains: ""double": 1.5," and contains: ""true": true," and contains: ""false": false," and contains: ""string": "this is a string"," and contains: ""array": [
+    1,
+    2
+  ]
+}" )
+Json.tests.cpp:<line number>: passed: stream.str(), ContainsSubstring( "\"empty_object\": {\n  }," ) && ContainsSubstring( "\"fully_object\": {\n    \"key\": 1\n  }" ) for: "{
+  "empty_object": {
+  },
+  "fully_object": {
+    "key": 1
+  }
+}" ( contains: ""empty_object": {
+  }," and contains: ""fully_object": {
+    "key": 1
+  }" )
+Json.tests.cpp:<line number>: passed: stream.str() == "[\n]" for: "[
+]"
+==
+"[
+]"
+Json.tests.cpp:<line number>: passed: stream.str() == "[\n  1,\n  1.5,\n  true,\n  false,\n  \"this is a string\",\n  {\n    \"object\": 42\n  },\n  [\n    \"array\",\n    42.5\n  ]\n]" for: "[
+  1,
+  1.5,
+  true,
+  false,
+  "this is a string",
+  {
+    "object": 42
+  },
+  [
+    "array",
+    42.5
+  ]
+]"
+==
+"[
+  1,
+  1.5,
+  true,
+  false,
+  "this is a string",
+  {
+    "object": 42
+  },
+  [
+    "array",
+    42.5
+  ]
+]"
+Json.tests.cpp:<line number>: passed: stream.str() == "{\n}" for: "{
+}"
+==
+"{
+}"
+Json.tests.cpp:<line number>: passed: stream.str() == "[\n]" for: "[
+]"
+==
+"[
+]"
+Json.tests.cpp:<line number>: passed: stream.str() == "\"custom\"" for: ""custom"" == ""custom""
+Json.tests.cpp:<line number>: passed: stream.str() == "\"\\\"\"" for: ""\""" == ""\"""
 Compilation.tests.cpp:<line number>: passed: []() { return true; }() for: true
 Approx.tests.cpp:<line number>: passed: d <= Approx( 1.24 ) for: 1.23 <= Approx( 1.24 )
 Approx.tests.cpp:<line number>: passed: d <= Approx( 1.23 ) for: 1.23 <= Approx( 1.23 )
@@ -1341,6 +1418,60 @@ Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring( "fa
 
 " ( contains: "fake test name" and contains: "fakeTestTag" ) with 1 message: 'Tested reporter: console'
 Reporters.tests.cpp:<line number>: passed: !(factories.empty()) for: !false
+Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring("fakeTag"s) for: "{
+  "version": 1,
+  "metadata": {
+    "name": "",
+    "rng-seed": 1234,
+    "catch2-version": "<version>"
+  },
+  "listings": {
+    "tags": [
+      {
+        "aliases": [
+          "fakeTag"
+        ],
+        "count": 1
+      }
+    ]" contains: "fakeTag" with 1 message: 'Tested reporter: JSON'
+Reporters.tests.cpp:<line number>: passed: !(factories.empty()) for: !false
+Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring("fake reporter"s) for: "{
+  "version": 1,
+  "metadata": {
+    "name": "",
+    "rng-seed": 1234,
+    "catch2-version": "<version>"
+  },
+  "listings": {
+    "reporters": [
+      {
+        "name": "fake reporter",
+        "description": "fake description"
+      }
+    ]" contains: "fake reporter" with 1 message: 'Tested reporter: JSON'
+Reporters.tests.cpp:<line number>: passed: !(factories.empty()) for: !false
+Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring( "fake test name"s ) && ContainsSubstring( "fakeTestTag"s ) for: "{
+  "version": 1,
+  "metadata": {
+    "name": "",
+    "rng-seed": 1234,
+    "catch2-version": "<version>"
+  },
+  "listings": {
+    "tests": [
+      {
+        "name": "fake test name",
+        "class-name": "",
+        "tags": [
+          "fakeTestTag"
+        ],
+        "source-location": {
+          "filename": "fake-file.cpp",
+          "line": 123456789
+        }
+      }
+    ]" ( contains: "fake test name" and contains: "fakeTestTag" ) with 1 message: 'Tested reporter: JSON'
+Reporters.tests.cpp:<line number>: passed: !(factories.empty()) for: !false
 Reporters.tests.cpp:<line number>: passed: listingString, ContainsSubstring("fakeTag"s) for: "<?xml version="1.0" encoding="UTF-8"?>
 All available tags:
    1  [fakeTag]
@@ -2533,7 +2664,7 @@ InternalBenchmark.tests.cpp:<line number>: passed: med == 18. for: 18.0 == 18.0
 InternalBenchmark.tests.cpp:<line number>: passed: q3 == 23. for: 23.0 == 23.0
 Misc.tests.cpp:<line number>: passed:
 Misc.tests.cpp:<line number>: passed:
-test cases:  413 |  308 passed |  85 failed | 6 skipped | 14 failed as expected
-assertions: 2230 | 2049 passed | 146 failed | 35 failed as expected
+test cases:  414 |  309 passed |  85 failed | 6 skipped | 14 failed as expected
+assertions: 2246 | 2065 passed | 146 failed | 35 failed as expected
 
 
diff --git a/tests/SelfTest/Baselines/console.std.approved.txt b/tests/SelfTest/Baselines/console.std.approved.txt
index 4ad25ed8..9aa0d038 100644
--- a/tests/SelfTest/Baselines/console.std.approved.txt
+++ b/tests/SelfTest/Baselines/console.std.approved.txt
@@ -1588,6 +1588,6 @@ due to unexpected exception with message:
   Why would you throw a std::string?
 
 ===============================================================================
-test cases:  413 |  322 passed |  70 failed | 7 skipped | 14 failed as expected
-assertions: 2213 | 2049 passed | 129 failed | 35 failed as expected
+test cases:  414 |  323 passed |  70 failed | 7 skipped | 14 failed as expected
+assertions: 2229 | 2065 passed | 129 failed | 35 failed as expected
 
diff --git a/tests/SelfTest/Baselines/console.sw.approved.txt b/tests/SelfTest/Baselines/console.sw.approved.txt
index d56e8c41..71cbbd27 100644
--- a/tests/SelfTest/Baselines/console.sw.approved.txt
+++ b/tests/SelfTest/Baselines/console.sw.approved.txt
@@ -7259,6 +7259,195 @@ with expansion:
   5 != 6
 
 -------------------------------------------------------------------------------
+JsonWriter
+  Newly constructed JsonWriter does nothing
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "" )
+with expansion:
+  "" == ""
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Calling writeObject will create an empty pair of braces
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "{\n}" )
+with expansion:
+  "{
+  }"
+  ==
+  "{
+  }"
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Calling writeObject with key will create an object to write the value
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE_THAT( stream.str(), ContainsSubstring( "\"int\": 1," ) && ContainsSubstring( "\"double\": 1.5," ) && ContainsSubstring( "\"true\": true," ) && ContainsSubstring( "\"false\": false," ) && ContainsSubstring( "\"string\": \"this is a string\"," ) && ContainsSubstring( "\"array\": [\n    1,\n    2\n  ]\n}" ) )
+with expansion:
+  "{
+    "int": 1,
+    "double": 1.5,
+    "true": true,
+    "false": false,
+    "string": "this is a string",
+    "array": [
+      1,
+      2
+    ]
+  }" ( contains: ""int": 1," and contains: ""double": 1.5," and contains:
+  ""true": true," and contains: ""false": false," and contains: ""string":
+  "this is a string"," and contains: ""array": [
+      1,
+      2
+    ]
+  }" )
+
+-------------------------------------------------------------------------------
+JsonWriter
+  nesting objects
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE_THAT( stream.str(), ContainsSubstring( "\"empty_object\": {\n  }," ) && ContainsSubstring( "\"fully_object\": {\n    \"key\": 1\n  }" ) )
+with expansion:
+  "{
+    "empty_object": {
+    },
+    "fully_object": {
+      "key": 1
+    }
+  }" ( contains: ""empty_object": {
+    }," and contains: ""fully_object": {
+      "key": 1
+    }" )
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Calling writeArray will create an empty pair of braces
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "[\n]" )
+with expansion:
+  "[
+  ]"
+  ==
+  "[
+  ]"
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Calling writeArray creates array to write the values to
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "[\n  1,\n  1.5,\n  true,\n  false,\n  \"this is a string\",\n  {\n    \"object\": 42\n  },\n  [\n    \"array\",\n    42.5\n  ]\n]" )
+with expansion:
+  "[
+    1,
+    1.5,
+    true,
+    false,
+    "this is a string",
+    {
+      "object": 42
+    },
+    [
+      "array",
+      42.5
+    ]
+  ]"
+  ==
+  "[
+    1,
+    1.5,
+    true,
+    false,
+    "this is a string",
+    {
+      "object": 42
+    },
+    [
+      "array",
+      42.5
+    ]
+  ]"
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Moved from JsonObjectWriter shall not insert superfluous brace
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "{\n}" )
+with expansion:
+  "{
+  }"
+  ==
+  "{
+  }"
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Moved from JsonArrayWriter shall not insert superfluous bracket
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "[\n]" )
+with expansion:
+  "[
+  ]"
+  ==
+  "[
+  ]"
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Custom class shall be quoted
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "\"custom\"" )
+with expansion:
+  ""custom"" == ""custom""
+
+-------------------------------------------------------------------------------
+JsonWriter
+  String with a quote shall be espaced
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "\"\\\"\"" )
+with expansion:
+  ""\""" == ""\"""
+
+-------------------------------------------------------------------------------
 Lambdas in assertions
 -------------------------------------------------------------------------------
 Compilation.tests.cpp:<line number>
@@ -9763,6 +9952,129 @@ with expansion:
 
 -------------------------------------------------------------------------------
 Reporter's write listings to provided stream
+  JSON reporter lists tags
+-------------------------------------------------------------------------------
+Reporters.tests.cpp:<line number>
+...............................................................................
+
+Reporters.tests.cpp:<line number>: PASSED:
+  REQUIRE_THAT( listingString, ContainsSubstring("fakeTag"s) )
+with expansion:
+  "{
+    "version": 1,
+    "metadata": {
+      "name": "",
+      "rng-seed": 1234,
+      "catch2-version": "<version>"
+    },
+    "listings": {
+      "tags": [
+        {
+          "aliases": [
+            "fakeTag"
+          ],
+          "count": 1
+        }
+      ]" contains: "fakeTag"
+with message:
+  Tested reporter: JSON
+
+-------------------------------------------------------------------------------
+Reporter's write listings to provided stream
+-------------------------------------------------------------------------------
+Reporters.tests.cpp:<line number>
+...............................................................................
+
+Reporters.tests.cpp:<line number>: PASSED:
+  REQUIRE_FALSE( factories.empty() )
+with expansion:
+  !false
+
+-------------------------------------------------------------------------------
+Reporter's write listings to provided stream
+  JSON reporter lists reporters
+-------------------------------------------------------------------------------
+Reporters.tests.cpp:<line number>
+...............................................................................
+
+Reporters.tests.cpp:<line number>: PASSED:
+  REQUIRE_THAT( listingString, ContainsSubstring("fake reporter"s) )
+with expansion:
+  "{
+    "version": 1,
+    "metadata": {
+      "name": "",
+      "rng-seed": 1234,
+      "catch2-version": "<version>"
+    },
+    "listings": {
+      "reporters": [
+        {
+          "name": "fake reporter",
+          "description": "fake description"
+        }
+      ]" contains: "fake reporter"
+with message:
+  Tested reporter: JSON
+
+-------------------------------------------------------------------------------
+Reporter's write listings to provided stream
+-------------------------------------------------------------------------------
+Reporters.tests.cpp:<line number>
+...............................................................................
+
+Reporters.tests.cpp:<line number>: PASSED:
+  REQUIRE_FALSE( factories.empty() )
+with expansion:
+  !false
+
+-------------------------------------------------------------------------------
+Reporter's write listings to provided stream
+  JSON reporter lists tests
+-------------------------------------------------------------------------------
+Reporters.tests.cpp:<line number>
+...............................................................................
+
+Reporters.tests.cpp:<line number>: PASSED:
+  REQUIRE_THAT( listingString, ContainsSubstring( "fake test name"s ) && ContainsSubstring( "fakeTestTag"s ) )
+with expansion:
+  "{
+    "version": 1,
+    "metadata": {
+      "name": "",
+      "rng-seed": 1234,
+      "catch2-version": "<version>"
+    },
+    "listings": {
+      "tests": [
+        {
+          "name": "fake test name",
+          "class-name": "",
+          "tags": [
+            "fakeTestTag"
+          ],
+          "source-location": {
+            "filename": "fake-file.cpp",
+            "line": 123456789
+          }
+        }
+      ]" ( contains: "fake test name" and contains: "fakeTestTag" )
+with message:
+  Tested reporter: JSON
+
+-------------------------------------------------------------------------------
+Reporter's write listings to provided stream
+-------------------------------------------------------------------------------
+Reporters.tests.cpp:<line number>
+...............................................................................
+
+Reporters.tests.cpp:<line number>: PASSED:
+  REQUIRE_FALSE( factories.empty() )
+with expansion:
+  !false
+
+-------------------------------------------------------------------------------
+Reporter's write listings to provided stream
   JUnit reporter lists tags
 -------------------------------------------------------------------------------
 Reporters.tests.cpp:<line number>
@@ -18283,6 +18595,6 @@ Misc.tests.cpp:<line number>
 Misc.tests.cpp:<line number>: PASSED:
 
 ===============================================================================
-test cases:  413 |  308 passed |  85 failed | 6 skipped | 14 failed as expected
-assertions: 2230 | 2049 passed | 146 failed | 35 failed as expected
+test cases:  414 |  309 passed |  85 failed | 6 skipped | 14 failed as expected
+assertions: 2246 | 2065 passed | 146 failed | 35 failed as expected
 
diff --git a/tests/SelfTest/Baselines/console.sw.multi.approved.txt b/tests/SelfTest/Baselines/console.sw.multi.approved.txt
index be965932..ccb27333 100644
--- a/tests/SelfTest/Baselines/console.sw.multi.approved.txt
+++ b/tests/SelfTest/Baselines/console.sw.multi.approved.txt
@@ -7257,6 +7257,195 @@ with expansion:
   5 != 6
 
 -------------------------------------------------------------------------------
+JsonWriter
+  Newly constructed JsonWriter does nothing
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "" )
+with expansion:
+  "" == ""
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Calling writeObject will create an empty pair of braces
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE( stream.str() == "{\n}" )
+with expansion:
+  "{
+  }"
+  ==
+  "{
+  }"
+
+-------------------------------------------------------------------------------
+JsonWriter
+  Calling writeObject with key will create an object to write the value
+-------------------------------------------------------------------------------
+Json.tests.cpp:<line number>
+...............................................................................
+
+Json.tests.cpp:<line number>: PASSED:
+  REQUIRE_THAT( stream.str(), ContainsSubstring( "\"int\": 1," ) && ContainsSubstring( "\"double\": 1.5," ) && ContainsSubstring( "\"true\": true," ) && ContainsSubstring( "\"false\": false," ) && ContainsSubstring( "\"string\": \"this is a string\"," ) && ContainsSubstring( "\"array\": [\n    1,\n    2\n  ]\n}" ) )
+with expansion:
+  "{
+    "int": 1,
+    "double": 1.5,
+    "true": true,
+    "false": false,
+    "string": "this is a string",
+    "array": [
+      1,
+      2
+    ]
+  }" ( contains: ""int": 1," and contains: ""double": 1.5," and contains:
+  ""true": true," and contains: ""false": false," and contains: ""string":
+  "this is a string"," and contains: ""array": [
+      1,
+      2
+    ]
+  }" )
+
+-------------------------------------------------------------------------------
+JsonWriter
+  nesting objects</