From 7474a2b6f45a36513657cdd61be24338124067ed Mon Sep 17 00:00:00 2001
From: Ju <soasme@users.noreply.github.com>
Date: Mon, 15 Feb 2021 18:12:38 +1300
Subject: [PATCH] Repeated expr should consume some input, otherwise
 AdvanceError. (#11)

---
 peppapeg.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/peppapeg.c b/peppapeg.c
index b4564374..5b5a1f53 100644
--- a/peppapeg.c
+++ b/peppapeg.c
@@ -732,6 +732,11 @@ P4_MatchRepeat(P4_Source* s, P4_Expression* e) {
         if (!NO_ERROR(s))
             goto finalize;
 
+        if (P4_GetPosition(s) == before_implicit) {
+            P4_RaiseError(s, P4_AdvanceError, "Repeated expression consumes no input");
+            goto finalize;
+        }
+
         repeated++;
         P4_AdoptToken(head, tail, tok);
 
@@ -739,6 +744,7 @@ P4_MatchRepeat(P4_Source* s, P4_Expression* e) {
             P4_RescueError(s);
             break;
         }
+
     }
 
     // there should be no error when repetition is successful.