static void test_format_commands(void) {
    char *cmd;
    int len;

    test("Format command without interpolation: ");
    len = redisFormatCommand(&cmd,"SET foo bar");
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$3\r\nfoo\r\n$3\r\nbar\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(3+2)+4+(3+2));
    hi_free(cmd);

    test("Format command with %%s string interpolation: ");
    len = redisFormatCommand(&cmd,"SET %s %s","foo","bar");
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$3\r\nfoo\r\n$3\r\nbar\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(3+2)+4+(3+2));
    hi_free(cmd);

    test("Format command with %%s and an empty string: ");
    len = redisFormatCommand(&cmd,"SET %s %s","foo","");
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$3\r\nfoo\r\n$0\r\n\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(3+2)+4+(0+2));
    hi_free(cmd);

    test("Format command with an empty string in between proper interpolations: ");
    len = redisFormatCommand(&cmd,"SET %s %s","","foo");
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$0\r\n\r\n$3\r\nfoo\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(0+2)+4+(3+2));
    hi_free(cmd);

    test("Format command with %%b string interpolation: ");
    len = redisFormatCommand(&cmd,"SET %b %b","foo",(size_t)3,"b\0r",(size_t)3);
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$3\r\nfoo\r\n$3\r\nb\0r\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(3+2)+4+(3+2));
    hi_free(cmd);

    test("Format command with %%b and an empty string: ");
    len = redisFormatCommand(&cmd,"SET %b %b","foo",(size_t)3,"",(size_t)0);
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$3\r\nfoo\r\n$0\r\n\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(3+2)+4+(0+2));
    hi_free(cmd);

    test("Format command with literal %%: ");
    len = redisFormatCommand(&cmd,"SET %% %%");
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$1\r\n%\r\n$1\r\n%\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(1+2)+4+(1+2));
    hi_free(cmd);

    /* Vararg width depends on the type. These tests make sure that the
     * width is correctly determined using the format and subsequent varargs
     * can correctly be interpolated. */
#define INTEGER_WIDTH_TEST(fmt, type) do {                                                \
    type value = 123;                                                                     \
    test("Format command with printf-delegation (" #type "): ");                          \
    len = redisFormatCommand(&cmd,"key:%08" fmt " str:%s", value, "hello");               \
    test_cond(strncmp(cmd,"*2\r\n$12\r\nkey:00000123\r\n$9\r\nstr:hello\r\n",len) == 0 && \
        len == 4+5+(12+2)+4+(9+2));                                                       \
    hi_free(cmd);                                                                         \
} while(0)

#define FLOAT_WIDTH_TEST(type) do {                                                       \
    type value = 123.0;                                                                   \
    test("Format command with printf-delegation (" #type "): ");                          \
    len = redisFormatCommand(&cmd,"key:%08.3f str:%s", value, "hello");                   \
    test_cond(strncmp(cmd,"*2\r\n$12\r\nkey:0123.000\r\n$9\r\nstr:hello\r\n",len) == 0 && \
        len == 4+5+(12+2)+4+(9+2));                                                       \
    hi_free(cmd);                                                                         \
} while(0)

    INTEGER_WIDTH_TEST("d", int);
    INTEGER_WIDTH_TEST("hhd", char);
    INTEGER_WIDTH_TEST("hd", short);
    INTEGER_WIDTH_TEST("ld", long);
    INTEGER_WIDTH_TEST("lld", long long);
    INTEGER_WIDTH_TEST("u", unsigned int);
    INTEGER_WIDTH_TEST("hhu", unsigned char);
    INTEGER_WIDTH_TEST("hu", unsigned short);
    INTEGER_WIDTH_TEST("lu", unsigned long);
    INTEGER_WIDTH_TEST("llu", unsigned long long);
    FLOAT_WIDTH_TEST(float);
    FLOAT_WIDTH_TEST(double);

    test("Format command with invalid printf format: ");
    len = redisFormatCommand(&cmd,"key:%08p %b",(void*)1234,"foo",(size_t)3);
    test_cond(len == -1);

    const char *argv[3];
    argv[0] = "SET";
    argv[1] = "foo\0xxx";
    argv[2] = "bar";
    size_t lens[3] = { 3, 7, 3 };
    int argc = 3;

    test("Format command by passing argc/argv without lengths: ");
    len = redisFormatCommandArgv(&cmd,argc,argv,NULL);
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$3\r\nfoo\r\n$3\r\nbar\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(3+2)+4+(3+2));
    hi_free(cmd);

    test("Format command by passing argc/argv with lengths: ");
    len = redisFormatCommandArgv(&cmd,argc,argv,lens);
    test_cond(strncmp(cmd,"*3\r\n$3\r\nSET\r\n$7\r\nfoo\0xxx\r\n$3\r\nbar\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(7+2)+4+(3+2));
    hi_free(cmd);

    sds sds_cmd;

    sds_cmd = NULL;
    test("Format command into sds by passing argc/argv without lengths: ");
    len = redisFormatSdsCommandArgv(&sds_cmd,argc,argv,NULL);
    test_cond(strncmp(sds_cmd,"*3\r\n$3\r\nSET\r\n$3\r\nfoo\r\n$3\r\nbar\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(3+2)+4+(3+2));
    sdsfree(sds_cmd);

    sds_cmd = NULL;
    test("Format command into sds by passing argc/argv with lengths: ");
    len = redisFormatSdsCommandArgv(&sds_cmd,argc,argv,lens);
    test_cond(strncmp(sds_cmd,"*3\r\n$3\r\nSET\r\n$7\r\nfoo\0xxx\r\n$3\r\nbar\r\n",len) == 0 &&
        len == 4+4+(3+2)+4+(7+2)+4+(3+2));
    sdsfree(sds_cmd);
}