marlinfirmware/marlin/marlin-unit-tests

Marlin Native Unit Tests

Background: test/README.md. For adding a test to a feature PR, see also the unit-test section of skill marlin-build-test.

Layout

• Test sources: Marlin/tests/<area>/test_<name>.cpp (Unity, MARLIN_TEST(group, name)).
• Test configurations: test/NNN-name.ini. Each one builds a separate test binary with a different Marlin configuration. Suites are discovered from this folder by buildroot/share/PlatformIO/scripts/collect-code-tests.py.
• The PlatformIO environment is linux_native_test in ini/native.ini. It is built on the Linux native HAL, with -Werror.

Run

make unit-test-all-local # all configs make unit-test-single-local UNIT_TEST_CONFIG=default # one config (test/001-default.ini) make unit-test-all-local-docker # same, in a container

Write one

1. Copy the license header and macros from an existing test, such as Marlin/tests/feature/test_runout.cpp.
2. Wrap the file in #if ENABLED(FEATURE) so it compiles only for configs that enable the feature.
3. If no test/*.ini enables the feature, add one with motherboard = BOARD_SIMULATED and only the options required to pass the sanity checks.
4. Test logic, not hardware: parsing, math, conversions, state machines. Anything needing real pins or timers isn't a good candidate.

macOS

On macOS /usr/bin/gcc is Clang, which cannot build Marlin. Install GCC with MacPorts or Homebrew, then:

buildroot/bin/mac_gcc macports # or: homebrew (apple resets to the system compiler) which gcc # should now be the real GCC

If the native build fails on macOS, first check the compiler diagnostics and which gcc you got. Don't assume the failure is a bug in the test wiring.

Pitfalls

• Test files are compiled with -Werror. An unused variable or sign-compare warning fails the run.
• Don't work around a compiler warning with duplicate includes or duplicate keys in the INI.
• Run the test configs one at a time. They share the .pio build directory.