On Wed, Nov 26, 2014 at 6:57 PM, Ian Cordasco <graffatcolmingov@gmail.com> wrote:
On Wed, Nov 26, 2014 at 10:51 AM, Keith Derrick <keith.derrick@lge.com> wrote:
I couldn't find anything in their bug list about this, so thought I'd check.
Just ran pylint at the command line with pylint 1.4 on this file (docstrings and import just to suppress miscellaneous complaints)
1 ''' Test file for pylint ''' 2 from __future__ import print_function 3 4 def method1(): 5 ''' Let x bleed from comprehension ''' 6 [x for x in range(3)] 7 print(x) 8 9 def method2(): 10 ''' reuse/hide x from local scope in comprehension ''' 11 y = 10 12 [y for y in range(3)] 13 print(y) 14
For python 2.7.6
************* Module bug W: 6, 4: Expression "[x for x in range(3)]" is assigned to nothing (expression-not-assigned) W: 7,10: Using possibly undefined loop variable 'x' (undefined-loop-variable) C: 11, 4: Invalid variable name "y" (invalid-name) W: 12, 4: Expression "[y for y in range(3)]" is assigned to nothing (expression-not-assigned) For python 3.4.0 ************* Module bug W: 6, 4: Expression "[x for x in range(3)]" is assigned to nothing (expression-not-assigned) E: 7,10: Undefined variable 'x' (undefined-variable) C: 11, 4: Invalid variable name "y" (invalid-name) W: 12, 4: Expression "[y for y in range(3)]" is assigned to nothing (expression-not-assigned)
So, it warns about the first case in py2 and gives an error in py3 which is expected.
But it seems to be confused by the second case, flagging "y" as an invalid variable-name at the assignment point for both versions.
Keith Derrick | Principal Engineer, Connected Platform | Engineering LG Silicon Valley Lab | 5150 Gt America Parkway, Santa Clara, CA 95054 Office: 408.610-5746 | Mobile: 831.383.9567 | LG.com
At this point, I'd recommend repling to the retitled message to catch the PyLint maintainer's focus.
We don't warn for this leak right now, but we are planning to add this in 1.5, under the --py3k checker. We just didn't have enough time to add this feature for this release. (See https://bitbucket.org/logilab/pylint/issue/376 for the remaining work related to the --py3k checker)