Add JSON reporter (#2706)

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

2 files changed, 119 insertions, 1 deletions

diff --git a/tests/SelfTest/IntrospectiveTests/Json.tests.cpp b/tests/SelfTest/IntrospectiveTests/Json.tests.cpp
new file mode 100644
index 00000000..9ade94ee
--- /dev/null
+++ b/tests/SelfTest/IntrospectiveTests/Json.tests.cpp
@@ -0,0 +1,116 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+#include <catch2/catch_test_macros.hpp>
+#include <catch2/internal/catch_jsonwriter.hpp>
+#include <catch2/matchers/catch_matchers_string.hpp>
+
+#include <sstream>
+
+namespace {
+    struct Custom {};
+    std::ostream& operator<<( std::ostream& os, Custom const& ) {
+        return os << "custom";
+    }
+} // namespace
+
+TEST_CASE( "JsonWriter", "[JSON][JsonWriter]" ) {
+
+    std::stringstream stream{};
+    SECTION( "Newly constructed JsonWriter does nothing" ) {
+        Catch::JsonValueWriter writer{ stream };
+        REQUIRE( stream.str() == "" );
+    }
+
+    SECTION( "Calling writeObject will create an empty pair of braces" ) {
+        { auto writer = Catch::JsonValueWriter{ stream }.writeObject(); }
+        REQUIRE( stream.str() == "{\n}" );
+    }
+
+    SECTION( "Calling writeObject with key will create an object to write the "
+             "value" ) {
+        using Catch::Matchers::ContainsSubstring;
+        {
+            auto writer = Catch::JsonValueWriter{ stream }.writeObject();
+            writer.write( "int" ).write( 1 );
+            writer.write( "double" ).write( 1.5 );
+            writer.write( "true" ).write( true );
+            writer.write( "false" ).write( false );
+            writer.write( "string" ).write( "this is a string" );
+            writer.write( "array" ).writeArray().write( 1 ).write( 2 );
+        }
+        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}" ) );
+    }
+
+    SECTION( "nesting objects" ) {
+        using Catch::Matchers::ContainsSubstring;
+        {
+            auto writer = Catch::JsonValueWriter{ stream }.writeObject();
+            writer.write( "empty_object" ).writeObject();
+            writer.write( "fully_object" )
+                .writeObject()
+                .write( "key" )
+                .write( 1 );
+        }
+        REQUIRE_THAT( stream.str(),
+                      ContainsSubstring( "\"empty_object\": {\n  }," ) &&
+                          ContainsSubstring(
+                              "\"fully_object\": {\n    \"key\": 1\n  }" ) );
+    }
+
+    SECTION( "Calling writeArray will create an empty pair of braces" ) {
+        { auto writer = Catch::JsonValueWriter{ stream }.writeArray(); }
+        REQUIRE( stream.str() == "[\n]" );
+    }
+
+    SECTION( "Calling writeArray creates array to write the values to" ) {
+        {
+            auto writer = Catch::JsonValueWriter{ stream }.writeArray();
+            writer.write( 1 );
+            writer.write( 1.5 );
+            writer.write( true );
+            writer.write( false );
+            writer.write( "this is a string" );
+            writer.writeObject().write( "object" ).write( 42 );
+            writer.writeArray().write( "array" ).write( 42.5 );
+        }
+        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]" );
+    }
+
+    SECTION(
+        "Moved from JsonObjectWriter shall not insert superfluous brace" ) {
+        {
+            auto writer = Catch::JsonObjectWriter{ stream };
+            auto another_writer = std::move( writer );
+        }
+        REQUIRE( stream.str() == "{\n}" );
+    }
+    SECTION(
+        "Moved from JsonArrayWriter shall not insert superfluous bracket" ) {
+        {
+            auto writer = Catch::JsonArrayWriter{ stream };
+            auto another_writer = std::move( writer );
+        }
+        REQUIRE( stream.str() == "[\n]" );
+    }
+    SECTION( "Custom class shall be quoted" ) {
+        Catch::JsonValueWriter{ stream }.write( Custom{} );
+        REQUIRE( stream.str() == "\"custom\"" );
+    }
+    SECTION( "String with a quote shall be espaced" ) {
+        Catch::JsonValueWriter{ stream }.write( "\"" );
+        REQUIRE( stream.str() == "\"\\\"\"" );
+    }
+}
diff --git a/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp b/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
index 1568c951..e5a65bda 100644
--- a/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
+++ b/tests/SelfTest/IntrospectiveTests/Reporters.tests.cpp
@@ -109,7 +109,9 @@ TEST_CASE( "Reporter's write listings to provided stream", "[reporters]" ) {
         auto sstream = Catch::Detail::make_unique<StringIStream>();
         auto& sstreamRef = *sstream.get();
 
-        Catch::Config config( Catch::ConfigData{} );
+        Catch::ConfigData cfg_data;
+        cfg_data.rngSeed = 1234;
+        Catch::Config config( cfg_data );
         auto reporter = factory.second->create( Catch::ReporterConfig{
             &config, CATCH_MOVE( sstream ), Catch::ColourMode::None, {} } );