Getting Started

AceUnit is a comfortable, test-discovery-based unit test framework for C, in the tradition of xUnit frameworks like JUnit. It targets developers writing firmware, drivers, operating systems, and other C programs — including in resource-constrained environments where most other frameworks don’t fit.

The idea

Write plain C functions. Name them by convention. AceUnit finds and runs them — no annotations, no macro-heavy test-registration boilerplate.

#include "leapyear.h"
#include <assert.h>

void testLeapYears(void) {
    assert(isLeapYear(0));
    assert(isLeapYear(4));
    assert(isLeapYear(400));
}

void testNonLeapYears(void) {
    assert(!isLeapYear(1));
    assert(!isLeapYear(100));
}

For each fixture (an object file with test cases), AceUnit looks for functions starting with:

• beforeAll() — one-time setup (0–1)
• beforeEach() — setup per test case (0–1)
• test() — test cases (n)
• afterEach() — teardown per test case (0–1)
• afterAll() — one-time teardown (0–1)

See Core Concepts for the full discovery model, including custom prefixes.

Install it

git clone https://github.com/christianhujer/aceunit.git
cd aceunit
make && sudo make install

Full details, prerequisites, and platform notes: Installation.

Run your first test

# Build your object files and test object files
cc -I /usr/local/include -c *.c

# Run aceunit on the test object files to generate fixture source
aceunit *_test.o >testcases.c

# Build the fixtures object file
cc -I /usr/local/include -c testcases.c

# Link against a runner and run
cc *.o -laceunit-abort
./a.out

AceUnit: 2 test cases, 2 successful, 0 failed.

That’s the whole workflow. Next: Core Concepts for how discovery and runners work, or Mocking if you need to test code with side effects.