diff --git a/jedi/cache.py b/jedi/cache.py
index a05988e4..56769d0d 100644
--- a/jedi/cache.py
+++ b/jedi/cache.py
@@ -212,7 +212,7 @@ def load_parser(path):
 
 def save_parser(path, parser, pickling=True):
     try:
-        p_time = os.path.getmtime(path)
+        p_time = None if path is None else os.path.getmtime(path)
     except OSError:
         p_time = None
         pickling = False
diff --git a/test/test_parser/test_fast_parser.py b/test/test_parser/test_fast_parser.py
index 73bc80a9..2b500872 100644
--- a/test/test_parser/test_fast_parser.py
+++ b/test/test_parser/test_fast_parser.py
@@ -81,7 +81,7 @@ def check_fp(src, number_parsers_used, number_of_splits=None, number_of_misses=0
         number_of_splits = number_parsers_used
 
     p = FastParser(load_grammar(), u(src))
-    cache.save_parser(None, None, p, pickling=False)
+    cache.save_parser(None, p, pickling=False)
 
     # TODO Don't change get_code, the whole thing should be the same.
     # -> Need to refactor the parser first, though.
@@ -352,7 +352,7 @@ def test_open_parentheses():
     assert p.module.get_code() == '\n\n' + func
     assert p.number_of_splits == 2
     assert p.number_parsers_used == 2
-    cache.save_parser(None, None, p, pickling=False)
+    cache.save_parser(None, p, pickling=False)
 
     # Now with a correct parser it should work perfectly well.
     check_fp('isinstance()\n' + func, 1, 2)