Contributing

Quick Start

# Desktop
cmake -S . -B cmake-build-desktop -G "Ninja Multi-Config"
cmake --build cmake-build-desktop --config Debug
ctest --test-dir cmake-build-desktop -C Debug --output-on-failure

# Emscripten
emcmake cmake -S . -B cmake-build-emscripten -G "Ninja Multi-Config" -D CMAKE_CXX_FLAGS="-fno-exceptions"
cmake --build cmake-build-emscripten --config Debug
ctest --test-dir cmake-build-emscripten -C Debug --output-on-failure

# AVR
cmake -S . -B cmake-build-avr-gcc -G "Ninja Multi-Config" -D CMAKE_TOOLCHAIN_FILE="cmake/toolchain/atmega328p.cmake"
cmake --build cmake-build-avr-gcc --config Debug

Project Layout

├── benchmarks  # Compile-time benchmarks
├── cmake       # Compiler config
├── docs        # Documentation
├── examples    # Simple demos which only require libc & tetl
├── fuzzing     # LLVM libFuzzer runner
├── include     # Source code
├── scripts     # Coverage & clang-tidy
└── tests       # Unit tests

Tests

Boilerplate for unit tests:

// SPDX-License-Identifier: BSL-1.0
#include <etl/utility.hpp>
 
#include "testing/testing.hpp"
 
namespace {
 
template <typename T>
constexpr auto test() -> bool
{
    CHECK(etl::cmp_equal(1, T(1)));
    CHECK_FALSE(etl::cmp_equal(-1, T(1)));
    CHECK_NOEXCEPT(etl::cmp_equal(-1, T(1)));
    CHECK_SAME_TYPE(decltype(etl::cmp_equal(-1, T(1))), bool);
 
    // more checks
    // ...
 
    return true;
}
 
constexpr auto test_all() -> bool
{
    CHECK(test<signed char>());
    CHECK(test<signed short>());
    CHECK(test<signed int>());
    CHECK(test<signed long>());
    CHECK(test<signed long long>());
 
    CHECK(test<unsigned char>());
    CHECK(test<unsigned short>());
    CHECK(test<unsigned int>());
    CHECK(test<unsigned long>());
    CHECK(test<unsigned long long>());
 
    // more custom types if needed
    // ...
 
    return true;
}
 
} // namespace
 
auto main() -> int
{
    // runs both assert & static_assert
    STATIC_CHECK(test_all());
 
    // runs only assert, use if constexpr is not supported
    // CHECK(test_all());
    return 0;
}

Tools

CMake Presets

cmake --list-presets=all .
cmake --preset desktop
cmake --build --preset desktop
ctest --preset desktop

clang-tidy

cmake -S . -B cmake-build-tidy -G "Unix Makefiles" -D CMAKE_BUILD_TYPE=Debug
cmake --build cmake-build-tidy --parallel 8
run-clang-tidy -fix -j 8 -quiet -p cmake-build-tidy -header-filter $(realpath .) $(realpath .)

coverage

# build with coverage flags
cmake -S . -B cmake-build-coverage -G Ninja -D CMAKE_BUILD_TYPE=Debug -D CMAKE_CXX_STANDARD=23 -D TETL_BUILD_COVERAGE=ON
cmake --build cmake-build-coverage --parallel 8
 
# run gcov
gcovr --html-details -e ".*_3rd_party*" --exclude-unreachable-branches -r . -s cmake-build-coverage -o cmake-build-coverage/coverage.html -j 4
 
# or grcov (faster)
grcov . -s . --binary-path ./cmake-build-coverage/bin/ -t html --ignore-not-existing -o ./cmake-build-coverage/html/ --ignore '*_3rd_party/*' --threads 4

pre-commit

pre-commit install
pre-commit run -a

doxygen

doxygen Doxyfile
open build-doxygen/html/index.html

VS Code

Enable one of the following options in .vscode/settings.json:

"cmake.useCMakePresets": "always"
"cmake.useCMakePresets": "never"

Coding Style

• Trailing return type is used everywhere:
  • auto func() {}
  • auto func() -> void;
  • auto func() -> double;
  • auto func() -> auto&;
  • auto func() -> decltype(auto);
• Keyword class is banned:
  • struct foo {};
  • enum struct foo { baz, baz };
  • template<typename T>
• Naming conventions:
  • Public interface matches the STL conventions
  • Checked via clang-tidy. See .clang-tidy config.
  • Local variables & parameters are camelBack
  • Template arguments are CamelCase
  • Private members have a "\_" prefix. e.g. int _val;