diff --git a/src/assets.c b/src/assets.c
index 561dd0c..f9502d5 100644
--- a/src/assets.c
+++ b/src/assets.c
@@ -169,7 +169,7 @@ cJSON* load_json_from_file(const char* filename) {
 }
 
 size_t json_array_len(cJSON* json) {
-    ASSERT_RETURN(!cJSON_IsArray(json), 0, "Tried to get the length of a non-array json element.");
+    ASSERT_RETURN(cJSON_IsArray(json), 0, "Tried to get the length of a non-array json element.");
     size_t len = 0;
     cJSON* itr;
     cJSON_ArrayForEach(itr, json) {