prevent inf loop on eseq zero-length sep and elt

flon-io · Jul 12, 2015 · 72e3adf · 72e3adf
1 parent 4340f7c
commit 72e3adf
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Showing 2 changed files with 29 additions and 5 deletions.
diff --git a/spec/fabr_eseq_spec.c b/spec/fabr_eseq_spec.c
@@ -290,6 +290,23 @@ describe "fabr_eseq()"
   context "with zero-length elements and separators"
   {
     it "works"
+    {
+      i.string = "<a,,a>";
+      i.flags = FABR_F_PRUNE;
+
+      t = fabr_eseq("B", &i, _es_sta, _es_el, _es_se, _es_end);
+
+      ensure(fabr_tree_to_string(t, i.string, 0) ===f ""
+        "[ \"B\", 1, 0, 6, null, \"eseq\", 0, [\n"
+        "  [ null, 1, 0, 1, null, \"str\", 1, \"<\" ],\n"
+        "  [ \"e\", 1, 1, 1, null, \"rex\", 2, \"a\" ],\n"
+        "  [ null, 1, 2, 1, null, \"rex\", 2, \",\" ],\n"
+        "  [ \"e\", 1, 3, 0, null, \"rex\", 2, \"\" ],\n"
+        "  [ null, 1, 3, 1, null, \"rex\", 2, \",\" ],\n"
+        "  [ \"e\", 1, 4, 1, null, \"rex\", 2, \"a\" ],\n"
+        "  [ null, 1, 5, 1, null, \"str\", 1, \">\" ]\n"
+        "] ]");
+    }
   }
 }
 
diff --git a/src/aabro.c b/src/aabro.c
@@ -1105,11 +1105,18 @@ fabr_tree *fabr_eseq(
 
     // determine r->result
 
-    if (st && st->result == 0) over = 1;
-    else if (st && st->result == -1) r->result = -1;
-    else if (st && st->result == 1 && st->length == 0 && et->result == 0) over = 2;
-    else if (j == 0 && et && et->result == 0 && jseq == 0) over = 1;
-    else if (et && et->result != 1) r->result = et->result;
+    if (st && st->result == 0)
+      over = 1;
+    else if (st && st->result == -1)
+      r->result = -1;
+    else if (st && st->result == 1 && st->length == 0 && et->result == 0)
+      over = 2;
+    else if (st && st->result == 1 && st->length == 0 && et->result == 1 && et->length == 0)
+      over = 2;
+    else if (j == 0 && et && et->result == 0 && jseq == 0)
+      over = 1;
+    else if (et && et->result != 1)
+      r->result = et->result;
 
     // add or free