TAP (Test Anything Protocol) in C

c-tap-test.h

/* from https://www.lemoda.net/c/simple-tap-test/ */

static int tap_count;
static int tap_todo;
static int tap_fail;

#define ENDLINE {				\
	if (tap_todo) {				\
	    printf (" # TODO\n");		\
	}					\
	else {					\
	    printf ("\n");			\
	}					\
    }

#define TAP_TEST(x) {					\
	tap_count++;					\
	if (! (x)) {					\
	    if (! tap_todo) {				\
		tap_fail++;				\
	    }						\
	    printf ("not ");				\
	}						\
	printf ("ok %d - %s", tap_count, #x);		\
	ENDLINE;					\
    }

#define TAP_TEST_EQUAL(x,y) {					\
	int xval = (int) x;					\
	int yval = (int) y;					\
	tap_count++;						\
	if (! (xval == yval)) {					\
	    if (! tap_todo) {					\
		tap_fail++;					\
	    }							\
	    printf ("not ");					\
	}							\
	printf ("ok %d - %s (%d) == %s (%d)", tap_count,	\
		#x, xval, #y, yval);				\
	ENDLINE;						\
    }

#define TAP_TEST_MSG(x,msg,args...) {			\
	tap_count++;					\
	if (! (x)) {					\
	    if (! tap_todo) {				\
		tap_fail++;				\
	    }						\
	    printf ("not ");				\
	}						\
	printf ("ok %d - ", tap_count);			\
	printf (msg, ## args);				\
	ENDLINE;					\
    }

#define TODO tap_todo = 1
#define END_TODO tap_todo = 0

#define TAP_PLAN {				\
	printf ("1..%d\n", tap_count);		\
    }

c-tap-test.manpage

NAME
     c-tap-test

SYNOPSIS
     #include <stdio.h>
     #include "c-tap-test.h"
     int main ()
     {
         int a = 1, b = 1, c = 2;
         TAP_TEST (a==b);
         TAP_TEST_EQUAL (a, b);
         TAP_TEST_MSG (a==b, "a %d is the same as b %d", a, b);
         TODO;
         TAP_TEST(a==c);
         END_TODO;
         TAP_PLAN;
         return tap_fail;
     }

MACROS
   TAP_TEST
     TAP_TEST(condition)

     If the condition is true, pass a test. If the condition is false, fail a test.

   TAP_TEST_MSG
     TAP_TEST_MSG(condition, format, ...)

     If the condition is true, pass a test. If the condition is false, fail a test. In either case, print a message
     using "format".

   TAP_TEST_EQUAL
     TAP_TEST_EQUAL(x, y)

     If x and y are equal, considered as integers, pass a test. If x and y are not equal, considered as integers, fail
     a test.

   TODO/END_TODO
     Start and stop the TAP todo test format.

   TAP_PLAN
     Print the plan for the TAP test, the numbers indicating the tests taken.

GLOBAL VARIABLES
     This header uses static global variables as follows.

   tap_count
     The total number of tests seen so far, as printed by TAP_PLAN.

   tap_todo
     True or false depending on whether in a to-do section. Toggled by TODO and END_TODO.

   tap_fail
     The number of failed tests, not including to-do tests.

simple-tap-test.c

/* from https://www.lemoda.net/c/simple-tap-test/ */

#include <stdio.h>

#include "c-tap-test.h"

int main ()
{
    int x;
    TAP_TEST (1 == 1);
    TAP_TEST_MSG (1 + 1 == 2, "one plus one equals two");
    x = 4;
    TAP_TEST_MSG (x + 1 == 5, "%d plus one equals five", x);
    TODO;
    TAP_TEST (1 == 0);

    END_TODO;
    TAP_PLAN;
    return 0;
}