Fix the fast parser issue #589.

jedi/parser/fast.py

@@ -424,14 +424,12 @@ class FastParser(use_metaclass(CachedFastParser)):
         """
         Side effect: Alters the list of nodes.
         """
-        indent = len(source) - len(source.lstrip('\t '))
-        self.current_node = self.current_node.parent_until_indent(indent)
-
         h = hash(source)
         for index, node in enumerate(nodes):
             if node.hash == h and node.source == source:
                 node.reset_node()
                 nodes.remove(node)
+                parser_code = source
                 break
         else:
             tokenizer = FastTokenizer(parser_code)
@@ -444,6 +442,9 @@ class FastParser(use_metaclass(CachedFastParser)):
 
             node = ParserNode(self.module, p, code_part_actually_used)
 
+        indent = len(parser_code) - len(parser_code.lstrip('\t '))
+        self.current_node = self.current_node.parent_until_indent(indent)
+
         self.current_node.add_node(node, line_offset)
         return node
 

test/test_parser/test_fast_parser.py

@@ -447,11 +447,14 @@ def test_decorator_string_issue():
     """
     Test case from #589
     """
-    s = jedi.Script(dedent('''\
+    source = dedent('''\
     """
       @"""
     def bla():
       pass
 
-    bla.'''))
+    bla.''')
+
+    s = jedi.Script(source)
     assert s.completions()
+    assert s._parser.module().get_code() == source