Fix an issue with nested flows in the diff parser.

jedi/parser/fast.py

@@ -11,7 +11,7 @@ from jedi._compatibility import use_metaclass
 from jedi import settings
 from jedi.common import splitlines
 from jedi.parser import ParserWithRecovery
-from jedi.parser.tree import Module, search_ancestor, EndMarker
+from jedi.parser.tree import Module, search_ancestor, EndMarker, Flow
 from jedi.parser.utils import parser_cache
 from jedi import debug
 from jedi.parser.tokenize import (generate_tokens, NEWLINE, TokenInfo,
@@ -360,6 +360,11 @@ class DiffParser(object):
         if parent == nodes[0].get_parent_scope():
             check_nodes = nodes
         else:
+            n = parent
+            while n is not None:
+                if isinstance(n, Flow):
+                    parent = n.get_parent_scope()
+                n = n.parent
             check_nodes = parent.children
 
         last_node = check_nodes[-1]
@@ -386,7 +391,6 @@ class DiffParser(object):
                 if n.last_leaf().type == 'newline':
                     break
         elif _is_flow_node(last_node):
-            # TODO the flows might be part of lower scopes... XXX
             # If we just copy flows at the end, they might be continued
             # after the copy limit (in the new parser).
             drop_node_count += 1

test/test_parser/test_diff_parser.py

@@ -318,3 +318,15 @@ def test_unfinished_nodes(differ):
     ''')
     differ.initialize(code)
     differ.parse(code2, parsers=1, copies=2)
+
+
+def test_nested_if_and_scopes(differ):
+    code = dedent('''
+    class a():
+        if 1:
+            def b():
+                2
+    ''')
+    code2 = code + '    else:\n        3'
+    differ.initialize(code)
+    differ.parse(code2, parsers=1, copies=0)