phonerail/firmware/test/test_cmd_json.c

/* A12：命令行的扁平 JSON 解析器（cmd_json.h）。

   这一层的测试重点不是「合法的能解出来」，而是**不合法的一律拒**：
   请求形状越窄，越界输入的面就越小。每一条「刻意不支持」都在这里钉一条用例 ——
   哪天有人为了「兼容」放宽了其中一条，这里先红。 */
#include <stdio.h>
#include <string.h>

#include "cmd_json.h"
#include "unity.h"

void setUp(void) {}
void tearDown(void) {}

static cj_obj_t o;

static void test_parses_a_flat_command(void)
{
    TEST_ASSERT_TRUE(cj_parse("{\"seq\":17,\"cmd\":\"key\",\"rail\":3,\"keys\":\"pwr+vdn\","
                              "\"ms\":2000,\"on\":true,\"x\":false,\"neg\":-5}\r\n",
                              &o));
    int64_t     v = 0;
    const char *s = NULL;
    bool        bv = false;
    TEST_ASSERT_EQUAL_INT(1, cj_get_int(&o, "seq", &v));
    TEST_ASSERT_EQUAL_INT64(17, v);
    TEST_ASSERT_EQUAL_INT(1, cj_get_str(&o, "cmd", &s));
    TEST_ASSERT_EQUAL_STRING("key", s);
    TEST_ASSERT_EQUAL_INT(1, cj_get_str(&o, "keys", &s));
    TEST_ASSERT_EQUAL_STRING("pwr+vdn", s);
    TEST_ASSERT_EQUAL_INT(1, cj_get_bool(&o, "on", &bv));
    TEST_ASSERT_TRUE(bv);
    TEST_ASSERT_EQUAL_INT(1, cj_get_bool(&o, "x", &bv));
    TEST_ASSERT_FALSE(bv);
    TEST_ASSERT_EQUAL_INT(1, cj_get_int(&o, "neg", &v));
    TEST_ASSERT_EQUAL_INT64(-5, v);
    TEST_ASSERT_EQUAL_INT(0, cj_get_int(&o, "missing", &v));
}

static void test_whitespace_and_empty_object(void)
{
    TEST_ASSERT_TRUE(cj_parse("  { \"a\" : 1 ,\t\"b\":\"x\" }  ", &o));
    TEST_ASSERT_EQUAL_INT(2, o.n);
    TEST_ASSERT_TRUE(cj_parse("{}", &o));
    TEST_ASSERT_EQUAL_INT(0, o.n);
}

/* 「有但类型不对」与「没有」是两回事：`"mv":"3900"` 是上位机的 bug，不是「没给电压」。 */
static void test_wrong_type_is_distinguished_from_missing(void)
{
    TEST_ASSERT_TRUE(cj_parse("{\"mv\":\"3900\",\"on\":1,\"cmd\":5}", &o));
    int64_t     v = 0;
    const char *s = NULL;
    bool        b = false;
    TEST_ASSERT_EQUAL_INT(-1, cj_get_int(&o, "mv", &v));
    TEST_ASSERT_EQUAL_INT(-1, cj_get_bool(&o, "on", &b)); /* 1 不是布尔 */
    TEST_ASSERT_EQUAL_INT(-1, cj_get_str(&o, "cmd", &s));
}

static void test_rejects_everything_outside_the_flat_shape(void)
{
    static const char *const bad[] = {
        "",                                   /* 空行 */
        "[1,2]",                              /* 不是对象 */
        "{\"a\":{\"b\":1}}",                  /* 嵌套 */
        "{\"a\":[1]}",                        /* 数组 */
        "{\"a\":null}",                       /* null */
        "{\"a\":3.9}",                        /* 浮点：不许被截成 3 */
        "{\"a\":1e3}",                        /* 指数 */
        "{\"a\":010}",                        /* 前导零 */
        "{\"a\":1234567890123456789}",        /* 19 位：不回绕 */
        "{\"a\":\"x\\\"y\"}",                 /* 转义：见头文件 */
        "{\"a\":\"line\nbreak\"}",            /* 控制字符 */
        "{\"mv\":3900,\"mv\":4300}",          /* 重复键：有人拿来绕校验的那种 */
        "{\"a\":1}{\"b\":2}",                 /* 两条命令粘在一行 */
        "{\"a\":1} x",                        /* 尾巴 */
        "{\"a\":1,}",                         /* 尾逗号 */
        "{\"a\" 1}",                          /* 缺冒号 */
        "{\"\":1}",                           /* 空键 */
        "{a:1}",                              /* 键没引号 */
        "{\"a\":tru}",                        /* 半个 true */
        "{\"a\":1",                           /* 没收尾 */
        "{\"a\":-}",                          /* 光一个负号 */
    };
    for (size_t i = 0; i < sizeof(bad) / sizeof(bad[0]); i++) {
        TEST_ASSERT_FALSE_MESSAGE(cj_parse(bad[i], &o), bad[i]);
    }
    TEST_ASSERT_FALSE(cj_parse(NULL, &o));
}

/* 超长的键 / 字符串不截断：截断会把 "set_voltage_x" 读成另一条命令。 */
static void test_overlong_tokens_are_rejected_not_truncated(void)
{
    char line[128];
    memset(line, 0, sizeof(line));
    strcpy(line, "{\"cmd\":\"");
    memset(line + strlen(line), 'a', CMD_JSON_STR_MAX); /* 32 个字符：装不下结尾 0 */
    strcat(line, "\"}");
    TEST_ASSERT_FALSE(cj_parse(line, &o));

    memset(line, 0, sizeof(line));
    strcpy(line, "{\"");
    memset(line + 2, 'k', CMD_JSON_KEY_MAX); /* 16 个：装不下结尾 0 */
    line[2 + CMD_JSON_KEY_MAX] = '\0';
    strcat(line, "\":1}");
    TEST_ASSERT_FALSE(cj_parse(line, &o));

    memset(line, 0, sizeof(line));
    strcpy(line, "{\"cmd\":\"");
    memset(line + strlen(line), 'a', CMD_JSON_STR_MAX - 1); /* 31 个 + 结尾 0：刚好装得下 */
    strcat(line, "\"}");
    TEST_ASSERT_TRUE(cj_parse(line, &o));
}

static void test_field_count_is_bounded(void)
{
    char line[256] = "{";
    for (int i = 0; i < CMD_JSON_MAX_FIELDS + 1; i++) {
        char f[16];
        snprintf(f, sizeof(f), "%s\"k%d\":%d", i ? "," : "", i, i);
        strcat(line, f);
    }
    strcat(line, "}");
    TEST_ASSERT_FALSE(cj_parse(line, &o));
}

static void test_writer_never_overruns(void)
{
    char        buf[8];
    cj_writer_t w;
    cj_w_init(&w, buf, sizeof(buf));
    cj_w(&w, "abc");
    TEST_ASSERT_FALSE(w.overflow);
    cj_w(&w, "defgh"); /* 3 + 5 = 8，装不下结尾 0 */
    TEST_ASSERT_TRUE(w.overflow);
    TEST_ASSERT_EQUAL_STRING("abc", buf); /* 写了一半的那段撤掉 */
    cj_w(&w, "x");
    TEST_ASSERT_EQUAL_STRING("abc", buf); /* 溢出之后一律不写 */
}

int main(void)
{
    UNITY_BEGIN();
    RUN_TEST(test_parses_a_flat_command);
    RUN_TEST(test_whitespace_and_empty_object);
    RUN_TEST(test_wrong_type_is_distinguished_from_missing);
    RUN_TEST(test_rejects_everything_outside_the_flat_shape);
    RUN_TEST(test_overlong_tokens_are_rejected_not_truncated);
    RUN_TEST(test_field_count_is_bounded);
    RUN_TEST(test_writer_never_overruns);
    return UNITY_END();
}