test: add tests for json parser/formatter

This should have been done sooner.

test/json.c

@@ -0,0 +1,86 @@
+#include "test_helpers.h"
+
+#include "common/common.h"
+#include "misc/json.h"
+#include "misc/node.h"
+
+struct entry {
+    const char *src;
+    const char *out_txt;
+    struct mpv_node out_data;
+    bool expect_fail;
+};
+
+#define TEXT(...) #__VA_ARGS__
+
+#define VAL_LIST(...) (struct mpv_node[]){__VA_ARGS__}
+
+#define L(...) __VA_ARGS__
+
+#define NODE_INT64(v) {.format = MPV_FORMAT_INT64,  .u = { .int64 = (v) }}
+#define NODE_STR(v)   {.format = MPV_FORMAT_STRING, .u = { .string = (v) }}
+#define NODE_BOOL(v)  {.format = MPV_FORMAT_FLAG,   .u = { .flag = (bool)(v) }}
+#define NODE_FLOAT(v) {.format = MPV_FORMAT_DOUBLE, .u = { .double_ = (v) }}
+#define NODE_NONE()   {.format = MPV_FORMAT_NONE }
+#define NODE_ARRAY(...) {.format = MPV_FORMAT_NODE_ARRAY, .u = { .list =    \
+    &(struct mpv_node_list) {                                               \
+        .num = sizeof(VAL_LIST(__VA_ARGS__)) / sizeof(struct mpv_node),     \
+        .values = VAL_LIST(__VA_ARGS__)}}}
+#define NODE_MAP(k, v) {.format = MPV_FORMAT_NODE_MAP, .u = { .list =       \
+    &(struct mpv_node_list) {                                               \
+        .num = sizeof(VAL_LIST(v)) / sizeof(struct mpv_node),               \
+        .values = VAL_LIST(v),                                              \
+        .keys = (char**)(const char *[]){k}}}}
+
+static const struct entry entries[] = {
+    { "null", "null", NODE_NONE()},
+    { "true", "true", NODE_BOOL(true)},
+    { "false", "false", NODE_BOOL(false)},
+    { "", .expect_fail = true},
+    { "abc", .expect_fail = true},
+    { "  123  ", "123", NODE_INT64(123)},
+    { "123.25", "123.250000", NODE_FLOAT(123.25)},
+    { TEXT("a\n\\"), TEXT("a\u000a\u005c"), NODE_STR("a\n\\")},
+    { "[1,2,3]", "[1,2,3]",
+        NODE_ARRAY(NODE_INT64(1), NODE_INT64(2), NODE_INT64(3))},
+    { "[ ]", "[]", NODE_ARRAY()},
+    { "[1,2,]", .expect_fail = true},
+    { "[1,,2]", .expect_fail = true},
+    { TEXT({"a":1, "b":2}), TEXT({"a":1,"b":2}),
+        NODE_MAP(L("a", "b"), L(NODE_INT64(1), NODE_INT64(2)))},
+    { "{ }", "{}", NODE_MAP(L(), L())},
+    { TEXT({"a":b}), .expect_fail = true},
+    { TEXT({a:"b"}), .expect_fail = true},
+    { TEXT({"a":1,}), .expect_fail = true},
+};
+
+#define MAX_DEPTH 10
+
+static void test_json(void **state)
+{
+    for (int n = 0; n < MP_ARRAY_SIZE(entries); n++) {
+        const struct entry *e = &entries[n];
+        print_message("%d: %s\n", n, e->src);
+        void *tmp = talloc_new(NULL);
+        char *s = talloc_strdup(tmp, e->src);
+        json_skip_whitespace(&s);
+        struct mpv_node res;
+        bool ok = json_parse(tmp, &res, &s, MAX_DEPTH) >= 0;
+        assert_true(ok != e->expect_fail);
+        if (!ok)
+            continue;
+        char *d = talloc_strdup(tmp, "");
+        assert_true(json_write(&d, &res) >= 0);
+        assert_string_equal(e->out_txt, d);
+        assert_true(equal_mpv_node(&e->out_data, &res));
+        talloc_free(tmp);
+    }
+}
+
+int main(void) {
+    const struct CMUnitTest tests[] = {
+        cmocka_unit_test(test_json),
+    };
+    return cmocka_run_group_tests(tests, NULL, NULL);
+}
+