minitest in c

#include <stdio.h>

// miniunit
// source: http://www.jera.com/techinfo/jtns/jtn002.html
#define mu_assert(message, test) do { if (!(test)) return message; } while (0)
#define mu_run_test(test) do { char *message = test(); tests_run++; \
  if (message) return message; } while (0)
extern int tests_run;


// test
int tests_run = 0;

int foo = 8;

static char * test_foo() {
  mu_assert("error, foo != 7", foo == 99);
  return 0;
}


// test runner

static char * all_tests() {
  mu_run_test(test_foo);
  return 0;
}

int main(int argc, char *argv[]) {
  char *results = all_tests();
  if(results != 0) {
    printf("%s\n", results);
  } else {
    printf("all passed");
  }
  return results != 0;
}