Return statements should be handled correctly if the return_stmt is only a return without an expression behind it.

jedi/evaluate/representation.py

@@ -335,7 +335,12 @@ class FunctionExecutionContext(context.TreeContext):
                 if check_yields:
                     types |= set(self._eval_yield(r))
                 else:
-                    types |= self.eval_node(r.children[1])
+                    try:
+                        children = r.children
+                    except AttributeError:
+                        types.add(compiled.create(self.evaluator, None))
+                    else:
+                        types |= self.eval_node(children[1])
             if check is flow_analysis.REACHABLE:
                 debug.dbg('Return reachable: %s', r)
                 break

test/completion/functions.py

@@ -1,3 +1,9 @@
+def x():
+    return
+
+#? None
+x()
+
 def array(first_param):
     #? ['first_param']
     first_param