Fix nested comprehension contexts, fixes #1691

jedi/inference/context.py

@@ -255,8 +255,7 @@ class TreeContextMixin:
             if scope_node.type in ('funcdef', 'lambdef', 'classdef'):
                 return self.create_value(scope_node).as_context()
             elif scope_node.type in ('comp_for', 'sync_comp_for'):
-                parent_scope = parser_utils.get_parent_scope(scope_node)
-                parent_context = from_scope_node(parent_scope)
+                parent_context = from_scope_node(parent_scope(scope_node.parent))
                 if node.start_pos >= scope_node.children[-1].start_pos:
                     return parent_context
                 return CompForContext(parent_context, scope_node)

test/completion/usages.py

@@ -310,6 +310,13 @@ z = 3
 #< 10 (0,1), (0,10)
 {z:1 for  z in something}
 
+#< 8 (0,6), (0, 40)
+[[x + nested_loopv2 for x in bar()] for nested_loopv2 in baz()]
+
+#< 25 (0,20), (0, 65)
+(("*" if abs(foo(x, nested_loopv1)) else " " for x in bar()) for nested_loopv1 in baz())
+
+
 def whatever_func():
     zzz = 3
     if UNDEFINED:

test/run.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 """
 |jedi| is mostly being tested by what I would call "integration tests". These
 tests are testing type inference with the public API. This makes a