Require __future__.print_function

[jayvdb]

It would be nice to force requiring __future__.print_function only when a print is found.

And/Or somehow expose a 'uses print' flag per module, in a way that https://github.com/xZise/flake8-future-import/issues/1 could use the flag.

[JBKahn]

Recently I've been busy with the sharding library stuff but I'll look into this, thanks for the recommendation!

[JBKahn]

We could use the checker_state from here to flag a print as being used in python 2 style and that we've already logged that it should be using future, that way we won't warn you more than once? If I understood checker_state correctly.

[jayvdb]

checker_state does look like it will provide state, but only within one check. As a result, and not surprising, the two plugins cant work together. One of the plugins will need to understand the other syntax element.

I checked the pep8 code, and checker_state is not shared between checks of the same plugin, so the check would need to detect both future import and print function.

To understand future imports, flake8-future-import has a FutureImportVisitor which is an ast.NodeVisitor approach. pep257 uses a more raw ast solution, which was hardened in https://github.com/GreenSteam/pep257/pull/154 . After the flake8-print check switches to a logical line based check, neither of those two solutions will be usable. This plugin would need a regex based approach to future import detection. That shouldnt be too difficult to get 99% correct since we are given a logical line which simplifies some of the parsing. (After a bit of playing, it looks like pep8 does not split logical lines on ';' .)