From: Nicolas Williams <nico@cryptonector.com>
Date: Fri, 26 Dec 2014 20:37:38 +0000 (-0600)
Subject: Allow C-coded functions to `empty`
X-Git-Tag: jq-1.5rc1~27
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=906d2537b9d0384985ed6259ef77ca1bd3d503ed;p=jq

Allow C-coded functions to `empty`

Just return a jv_invalid() without a message.
---

diff --git a/execute.c b/execute.c
index e8fba19..231bd21 100644
--- a/execute.c
+++ b/execute.c
@@ -703,9 +703,13 @@ jv jq_next(jq_state *jq) {
       
       if (jv_is_valid(top)) {
         stack_push(jq, top);
-      } else {
+      } else if (jv_invalid_has_msg(jv_copy(top))) {
         set_error(jq, top);
         goto do_backtrack;
+      } else {
+        // C-coded function returns invalid w/o msg? -> backtrack, as if
+        // it had returned `empty`
+        goto do_backtrack;
       }
       break;
     }