FilesExpand file tree

 main

/

LeakingListComprehension.ql

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

31 lines (29 loc) · 1.07 KB

 main

/

LeakingListComprehension.ql

Copy path

Top

File metadata and controls

• Code
• Blame

31 lines (29 loc) · 1.07 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

/**

* @name List comprehension variable used in enclosing scope

* @description Using the iteration variable of a list comprehension in the enclosing scope will result in different behavior between Python 2 and 3 and is confusing.

* @kind problem

* @tags portability

* correctness

* @problem.severity warning

* @sub-severity high

* @precision very-high

* @id py/leaking-list-comprehension

*/

import python

import Definition

from ListComprehensionDeclaration l, Name use, Name defn

where

use = l.getALeakedVariableUse() and

defn = l.getDefinition() and

l.getAFlowNode().strictlyReaches(use.getAFlowNode()) and

/* Make sure we aren't in a loop, as the variable may be redefined */

not use.getAFlowNode().strictlyReaches(l.getAFlowNode()) and

not l.contains(use) and

not use.deletes(_) and

not exists(SsaVariable v |

v.getAUse() = use.getAFlowNode() and

not v.getDefinition().strictlyDominates(l.getAFlowNode())

)

select use,

use.getId() + " may have a different value in Python 3, as the $@ will not be in scope.", defn,

"list comprehension variable"