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Related occupations SOC
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name testing version 3.0.0 description Production-grade C++ testing expertise including unit testing, mocking, TDD, BDD, fuzzing, benchmark testing, coverage analysis, and CI integration.
sasmp_version 1.3.0 eqhm_compliant true last_audit 2025-12-30 bonded_agent cpp-debugger-agent bond_type PRIMARY_BOND fallback_agent modern-cpp-expert category quality-assurance complexity intermediate-advanced estimated_tokens 3000 activation_triggers {"keywords":["test","unit test","gtest","catch2","mock","gmock","tdd","bdd","coverage","fuzzing","benchmark"],"patterns":["write tests for","how to test","test coverage","mock object","test fixture"]} capabilities {"primary":["Unit test writing with Google Test and Catch2","Mock object creation with Google Mock","Test fixture design and setup","Parameterized and data-driven tests","Test-driven development workflow"],"secondary":["Fuzz testing with libFuzzer","Benchmark testing with Google Benchmark","Code coverage analysis (gcov, lcov)","CI/CD test pipeline setup","Property-based testing"]} input_schema {"type":"object","properties":{"code_to_test":{"type":"string","description":"C++ code or function to write tests for"},"framework":{"type":"string","enum":["gtest","catch2","boost_test","doctest"],"default":"gtest","description":"Testing framework to use"},"test_type":{"type":"string","enum":["unit","integration","benchmark","fuzz"],"default":"unit"},"coverage_target":{"type":"number","minimum":0,"maximum":100,"default":80,"description":"Target coverage percentage"}}} output_schema {"type":"object","properties":{"test_code":{"type":"string","description":"Generated test code"},"cmake_config":{"type":"string","description":"CMake configuration for tests"},"coverage_report":{"type":"object","description":"Coverage analysis results"},"recommendations":{"type":"array","items":{"type":"string"},"description":"Testing improvement suggestions"}}} error_handling {"retry_logic":{"max_attempts":3,"backoff":"exponential","initial_delay_ms":500,"max_delay_ms":8000,"jitter":true},"fallback":{"on_framework_error":"suggest_alternative_framework","on_compilation_error":"provide_build_guidance","on_coverage_error":"manual_coverage_check"}} observability {"logging":{"level":"INFO","format":"[%(timestamp)s] [%(skill)s] %(message)s"},"metrics":["tests_generated","coverage_achieved","frameworks_used"]}
C++ Testing Skill
Overview
Production-grade testing expertise for C++ applications. Master unit testing, mocking, TDD, and modern testing workflows.
Testing Frameworks
Google Test (gtest)
The most widely used C++ testing framework.
#include <gtest/gtest.h>
TEST (CalculatorTest, Addition) {
Calculator calc;
EXPECT_EQ (calc.add (2 , 3 ), 5 );
EXPECT_EQ (calc.add (-1 , 1 ), 0 );
}
class StackTest : public ::testing::Test {
protected :
void SetUp () override push (1 );
stack.push (2 );
}
void TearDown () override int > stack;
};
TEST_F (StackTest, PopReturnsTop) {
EXPECT_EQ (stack.pop (), 2 );
EXPECT_EQ (stack.size (), 1 );
}
class PrimeTest : public ::testing::TestWithParam<int
TEST_P
EXPECT_TRUE
isPrime
GetParam
INSTANTIATE_TEST_SUITE_P
Values
2
3
5
7
11
13
TEST
EXPECT_DEATH
dereference
nullptr
".*"
Catch2 Modern, header-only testing framework.
#define CATCH_CONFIG_MAIN
#include <catch2/catch.hpp>
TEST_CASE ("Vector operations" , "[vector]" ) {
std::vector<int > v;
SECTION ("pushing increases size" ) {
v.push_back (1 );
REQUIRE (v.size () == 1 );
}
SECTION ("popping decreases size" ) {
v.push_back (1 );
v.pop_back ();
REQUIRE (v.empty ());
}
}
SCENARIO ("Bank account operations" , "[account]" ) {
GIVEN ("An account with $100" ) {
Account account (100 ) ;
WHEN ("$50 is withdrawn" ) {
account.withdraw (50 );
THEN ("balance is $50" ) {
REQUIRE (account.balance () == 50 );
}
}
}
}
TEST_CASE ("String matchers" ) {
REQUIRE_THAT ("Hello World" , Catch::Contains ("World" ));
REQUIRE_THAT ("Hello" , Catch::StartsWith ("Hel" ));
}
Google Mock (gmock)
Creating Mocks #include <gmock/gmock.h>
class Database {
public :
virtual ~Database () = default ;
virtual bool connect (const std::string& url) 0 ;
virtual std::string query (const std::string& sql) 0 ;
virtual void disconnect () 0 ;
};
class MockDatabase : public Database {
public :
MOCK_METHOD (bool , connect, (const std::string& url), (override ));
MOCK_METHOD (std::string, query, (const std::string& sql), (override ));
MOCK_METHOD (void , disconnect, (), (override ));
};
TEST (UserServiceTest, FetchesUserFromDatabase) {
MockDatabase db;
UserService service (&db) ;
EXPECT_CALL (db, connect ("db://localhost" ))
.WillOnce (Return (true ));
EXPECT_CALL (db, query ("SELECT * FROM users WHERE id = 1" ))
.WillOnce (Return (R"({"name": "John"})" ));
EXPECT_CALL (db, disconnect ());
auto user = service.getUser (1 );
EXPECT_EQ (user.name, "John" );
}
Advanced Mocking
EXPECT_CALL (mock, method (
AllOf (Gt (0 ), Lt (100 )),
HasSubstr ("test" ),
_
));
EXPECT_CALL (mock, method (_))
.WillOnce (Return (42 ))
.WillOnce (Throw (std::runtime_error ("error" )))
.WillRepeatedly (ReturnArg <0 >());
Sequence s;
EXPECT_CALL (mock, first ()).InSequence (s);
EXPECT_CALL (mock, second ()).InSequence (s);
EXPECT_CALL (mock, method ())
.Times (AtLeast (1 ))
.Times (AtMost (5 ))
.Times (Between (2 , 4 ));
Test-Driven Development (TDD)
Red-Green-Refactor Cycle ┌─────────────────────────────────────────────────────────────┐
│ TDD WORKFLOW │
├─────────────────────────────────────────────────────────────┤
│ │
│ ┌───────┐ ┌───────┐ ┌──────────┐ │
│ │ RED │────▶│ GREEN │────▶│ REFACTOR │ │
│ └───────┘ └───────┘ └──────────┘ │
│ │ │ │
│ │ ┌───────────────────┘ │
│ │ │ │
│ ▼ ▼ │
│ Write failing test ─▶ Make it pass ─▶ Clean up code │
│ │
└─────────────────────────────────────────────────────────────┘
TDD Example
TEST (StringUtilsTest, ReverseString) {
EXPECT_EQ (reverse ("hello" ), "olleh" );
}
std::string reverse (const std::string& s) {
std::string result = s;
std::reverse (result.begin (), result.end ());
return result;
}
Fuzzing with libFuzzer
#include <cstdint>
#include <cstddef>
extern "C" int LLVMFuzzerTestOneInput (const uint8_t * data, size_t size) if (size < 4 ) return 0 ;
std::string input (reinterpret_cast <const char *>(data), size) ;
try {
parseJson (input);
} catch (...) {
}
return 0 ;
}
clang++ -fsanitize=fuzzer,address -g fuzz_target.cpp -o fuzzer
./fuzzer corpus/ -max_len=1024 -jobs =4
Benchmark Testing #include <benchmark/benchmark.h>
static void BM_VectorPushBack (benchmark::State& state) for (auto _ : state) {
std::vector<int > v;
for (int i = 0 ; i < state.range (0 ); ++i) {
v.push_back (i);
}
benchmark::DoNotOptimize (v);
}
}
BENCHMARK (BM_VectorPushBack)->Range (8 , 8 <<10 );
static void BM_VectorReserve (benchmark::State& state) for (auto _ : state) {
std::vector<int > v;
v.reserve (state.range (0 ));
for (int i = 0 ; i < state.range (0 ); ++i) {
v.push_back (i);
}
benchmark::DoNotOptimize (v);
}
}
BENCHMARK (BM_VectorReserve)->Range (8 , 8 <<10 );
BENCHMARK_MAIN ();
Code Coverage
Setup with CMake option(ENABLE_COVERAGE "Enable coverage reporting" OFF)
if(ENABLE_COVERAGE)
add_compile_options(--coverage -fprofile-arcs -ftest-coverage)
add_link_options(--coverage)
endif()
Generate Report
cmake -B build -DENABLE_COVERAGE=ON
cmake --build build
cd build && ctest
lcov --capture --directory . --output-file coverage.info
lcov --remove coverage.info '/usr/*' --output-file coverage.info
genhtml coverage.info --output-directory coverage_report
CMake Test Configuration cmake_minimum_required(VERSION 3.14)
project(MyProject)
# Enable testing
enable_testing()
# Fetch Google Test
include(FetchContent)
FetchContent_Declare(
googletest
GIT_REPOSITORY https://github.com/google/googletest.git
GIT_TAG v1.14.0
)
FetchContent_MakeAvailable(googletest)
# Add test executable
add_executable(tests
test_main.cpp
test_calculator.cpp
test_parser.cpp
)
target_link_libraries(tests
PRIVATE
GTest::gtest
GTest::gmock
GTest::gtest_main
mylib
)
# Register tests with CTest
include(GoogleTest)
gtest_discover_tests(tests)
CI Integration
GitHub Actions name: Tests
on: [push , pull_request ]
jobs:
test:
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@v4
- name: Configure
run: cmake -B build -DENABLE_COVERAGE=ON
- name: Build
run: cmake --build build
- name: Test
run: ctest --test-dir build --output-on-failure
- name: Coverage
run: |
lcov --capture --directory build --output-file coverage.info
bash <(curl -s https://codecov.io/bash)
Troubleshooting Decision Tree Test Failure
├── Compilation Error?
│ ├── Yes → Check includes, link libraries
│ └── No ↓
├── Assertion Failed?
│ ├── Yes → Debug actual vs expected values
│ └── No ↓
├── Segmentation Fault?
│ ├── Yes → Run with ASan, check pointers
│ └── No ↓
├── Timeout?
│ ├── Yes → Check infinite loops, deadlocks
│ └── No ↓
└── Flaky Test?
├── Yes → Check race conditions, random seeds
└── No → Check test isolation
Quick Reference Framework Header Main Macro Assertion GTest <gtest/gtest.h>TEST()EXPECT_*, ASSERT_*Catch2 <catch2/catch.hpp>TEST_CASE()REQUIRE(), CHECK()doctest <doctest/doctest.h>TEST_CASE()CHECK(), REQUIRE()
Unit Test Template #include <gtest/gtest.h>
#include "testing_skill.hpp"
class TestingSkillTest : public ::testing::Test {
protected :
void SetUp () override TEST_F (TestingSkillTest, GeneratesValidTests) {
std::string code = "int add(int a, int b) { return a + b; }" ;
auto tests = generateTests (code);
EXPECT_FALSE (tests.empty ());
EXPECT_THAT (tests, HasSubstr ("EXPECT_EQ" ));
}
TEST_F (TestingSkillTest, HandlesEmptyInput) {
EXPECT_THROW (generateTests ("" ), std::invalid_argument);
}
C++ Plugin v3.0.0 - Production-Grade Testing Skill
