使用几十行代码实现一个简约的C语言单元测试框架。该框架只有一个头文件，使用方法如下：

1. 引用头文件mcut.h
2. 编写测试函数（测试case），参数和返回值类型均为void。测试函数中使用mcut_assert、mcut_assert_msg、mcut_assert_int对测试结果进行判断
3. 调用mcut_run_test方法运行测试函数
4. 调用mcut_show_statistics，展示统计结果

框架代码，mcut.h：

/* mcut.h: Minimalist C Unit Test framework */
#ifndef __MCUT_H
#define __MCUT_H

#include <stdlib.h>
#include <stdio.h>

static int __MCUT_RAN = 0;
static int __MCUT_FAILED = 0;

#define mcut_assert_msg(expr, ...) \
do { \
    __MCUT_RAN++; \
    if (!(expr)) { \
        printf("%s(%d): ", __func__, __LINE__); \
        printf(__VA_ARGS__); \
        printf("\n"); \
        __MCUT_FAILED++; \
    } \
} while (0)

#define mcut_assert(expr) \
    mcut_assert_msg(expr, "Assertion '"#expr"' failed")

/* O may be any comparion operator. */
#define mcut_assert_int(X, O, Y) \
    mcut_assert_msg((X) O (Y), \
                    "Assertion '"#X#O#Y"' failed: "#X"==%d, "#Y"==%d", X, Y)

#define mcut_run_test(test_case) test_case()

#define mcut_show_statistics() \
do { \
    float passed = 0; \
    if (__MCUT_RAN != 0) { \
        passed = (__MCUT_RAN - __MCUT_FAILED) * 100.00 / __MCUT_RAN; \
    } \
    printf("\n---------- Run Summary ----------\n"); \
    printf("Passed: %.2f%%, Ran: %d, Failed: %d\n", \
           passed, __MCUT_RAN, __MCUT_FAILED); \
    if (__MCUT_FAILED) return 1; \
} while (0)

#endif

测试代码，test_sub.c：

#include <stdlib.h>
#include <stdio.h>
#include "mcut.h"

/* function */
int sub(int a, int b)
{
    return 0;
}

/* test case */
static void test_sub1(void)
{
    mcut_assert(sub(10, 5) == 5);
}

static void test_sub2(void)
{
    mcut_assert_msg(sub(2, 5) == -3, "Error: sub(2, 5) != -3");
}

static void test_sub3(void)
{
    mcut_assert_int(sub(2, 0), ==, 2);
}

static void test_sub4(void)
{
    mcut_assert_int(sub(0, 0), ==, 0);
}

/* run test case */
int main(int argc, char *argv[])
{
    mcut_run_test(test_sub1);
    mcut_run_test(test_sub2);
    mcut_run_test(test_sub3);
    mcut_run_test(test_sub4);

    mcut_show_statistics();
    return 0;
}

编译

# gcc -Wall test_sub.c -o test_sub

运行结果

# ./test_sub 
test_sub1(14): Assertion 'sub(10, 5) == 5' failed
test_sub2(19): Error: sub(2, 5) != -3
test_sub3(24): Assertion 'sub(2, 0)==2' failed: sub(2, 0)==0, 2==2

---------- Run Summary ----------
Passed: 25.00%, Ran: 4, Failed: 3