fix jq_fuzz_parse_stream: use iterative parser API for streaming mode (#3499)

tests/jq_fuzz_parse_stream.c

@@ -5,15 +5,27 @@
 #include "jv.h"
 
 int LLVMFuzzerTestOneInput(uint8_t *data, size_t size) {
-  // Creat null-terminated string
+  // Create null-terminated string
   char *null_terminated = (char *)malloc(size + 1);
   memcpy(null_terminated, (char *)data, size);
   null_terminated[size] = '\0';
 
-  // Fuzzer entrypoint
-  jv res = jv_parse_custom_flags(null_terminated, JV_PARSE_STREAMING);
-  jv_free(res);
-  
+  // Use the iterative jv_parser API for streaming mode.
+  // The single-shot jv_parse_custom_flags() returns "Unexpected extra JSON
+  // values" for any compound JSON in streaming mode, because the streaming
+  // parser produces multiple tokens but the single-shot API expects exactly
+  // one value.
+  jv_parser *parser = jv_parser_new(JV_PARSE_STREAMING);
+  jv_parser_set_buf(parser, null_terminated, (int)size, 0);
+
+  jv value;
+  while (jv_is_valid(value = jv_parser_next(parser))) {
+    jv_free(value);
+  }
+  jv_free(value);
+
+  jv_parser_free(parser);
+
   // Free the null-terminated string
   free(null_terminated);