Adding positive and negative unit test cases

Author: wravery

test/CMakeLists.txt

@@ -71,7 +71,7 @@ gtest_add_tests(TARGET pegtl_combined_tests)
 
 add_executable(pegtl_executable_tests PegtlExecutableTests.cpp)
 target_link_libraries(pegtl_executable_tests PRIVATE
-  taocpp::pegtl
+  graphqlpeg
   GTest::GTest
   GTest::Main)
 target_include_directories(pegtl_executable_tests PRIVATE

test/PegtlExecutableTests.cpp

@@ -3,6 +3,8 @@
 
 #include <gtest/gtest.h>
 
+#include "graphqlservice/GraphQLParse.h"
+
 #include "graphqlservice/internal/Grammar.h"
 
 #include <tao/pegtl/contrib/analyze.hpp>
@@ -169,6 +171,62 @@ TEST(PegtlExecutableCase, InvalidStringEscapeSequence)
 		caughtException = true;
 	}
 
+	EXPECT_TRUE(caughtException) << "should catch a parse exception";
+	EXPECT_FALSE(parsedQuery) << "should not successfully parse the query";
+}
+
+using namespace std::literals;
+
+constexpr auto queryWithDepth3 = R"gql(query {
+		foo {
+			bar
+		}
+	})gql"sv;
+
+TEST(PegtlExecutableCase, ParserDepthLimitNotExceeded)
+{
+	bool parsedQuery = false;
+
+	try
+	{
+		auto query = peg::parseString(queryWithDepth3, 3);
+
+		parsedQuery = query.root != nullptr;
+	}
+	catch (const peg::parse_error& ex)
+	{
+		FAIL() << ex.what();
+	}
+
+	EXPECT_TRUE(parsedQuery) << "should parse the query";
+}
+
+TEST(PegtlExecutableCase, ParserDepthLimitExceeded)
+{
+	bool parsedQuery = false;
+	bool caughtException = false;
+
+	try
+	{
+		auto query = peg::parseString(queryWithDepth3, 2);
+
+		parsedQuery = query.root != nullptr;
+	}
+	catch (const peg::parse_error& ex)
+	{
+		ASSERT_NE(nullptr, ex.what());
+
+		using namespace std::literals;
+
+		const std::string_view error { ex.what() };
+		constexpr auto expected =
+			"GraphQL:4:3: Exceeded 2 nested depth limit for https://spec.graphql.org/October2021/#SelectionSet"sv;
+
+		EXPECT_TRUE(error == expected) << ex.what();
+
+		caughtException = true;
+	}
+
 	EXPECT_TRUE(caughtException) << "should catch a parse exception";
 	EXPECT_FALSE(parsedQuery) << "should not successfully parse the query";
 }