format empty filter lists

jamescasbon · Sep 10, 2012 · 2a728f4 · 2a728f4
1 parent 27ee8e3
commit 2a728f4
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/vcf/parser.py b/vcf/parser.py
@@ -581,7 +581,9 @@ def _format_alt(self, alt):
         return ','.join(self._map(str, alt))
 
     def _format_filter(self, flt):
-        return self._stringify(flt, none='PASS', delim=';')
+        if flt == []:
+            return 'PASS'
+        return self._stringify(flt, none='.', delim=';')
 
     def _format_info(self, info):
         if not info: