Repeated expr should consume some input, otherwise AdvanceError. (#11)

soasme · Feb 15, 2021 · 7474a2b · 7474a2b
1 parent 5365b93
commit 7474a2b
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/peppapeg.c b/peppapeg.c
@@ -732,13 +732,19 @@ 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);
 
         if (max != -1 && repeated == max) { // enough attempts
             P4_RescueError(s);
             break;
         }
+
     }
 
     // there should be no error when repetition is successful.