List comprehensions and Python 3

Plone Support Add-on Development
1

I'm slowly implementing changes in our add-ons to make them Python 3 compatible using the --py3k parameter of Pylint.

on a recent automatic CI build in Travis I got the following error:

$ bin/pylint --py3k --disable=no-absolute-import src/collective/fingerpointing
No config file found, using default configuration
************* Module collective.fingerpointing.tests.test_upgrades
W: 85,17: Using a variable that was bound inside a comprehension (comprehension-escape)
W: 85,45: Using a variable that was bound inside a comprehension (comprehension-escape)
-------------------------------------------------------------------
Your code has been rated at 9.98/10 (previous run: 10.00/10, -0.02)

the code looks like this:

I manually tested it under Python 3 and I found no errors: besides that, a similar code is being used some lines above with no warnings.

according to Pylint this warning is:

Emitted when using a variable, that was bound in a comprehension handler, outside of the comprehension itself. On Python 3 these variables will be deleted outside of the comprehension.

which, IMO, is not the case.

may I just ignore this warning?

2

Agree, this is not the case..

Can you test pylint changing this part of the code without the if statement inside to see if this is the problem?

3

I think this is a false positive; as mentioned above the same code is used before with no errors. I opened a new issue:

UPDATE: Pylint's maintainer just confirmed this is a false positive.

1 Like