Issue 33251: ConfigParser.items returns items present in vars

The documentation for ConfigParser.items(section, raw=False, vars=None) says the following:

> Changed in version 3.2: Items present in vars no longer appear in the result. The previous behaviour mixed actual parser options with variables provided for interpolation.

https://docs.python.org/3/library/configparser.html#configparser.ConfigParser.items

However, this does not seem to be the case. The keys from vars are present in the output. Tested on 3.6.5.

This example shows the issue:

    import configparser

    config = configparser.ConfigParser()

    config.add_section('example')
    config.set('example', 'name', 'timster %(suffix)s')

    data = config.items('example', vars={'suffix': 'user'})

    print(data)


Expected output:

    [('name', 'timster user')]

Actual output:

    [('name', 'timster user'), ('suffix', 'user')]

Hm. The documentation change was done in issue12036 but it seems this was actually never the case, contrary to what the conversation on that other issue there states.

I wouldn't change it for 3.6.6 anymore since it's pretty late in the release cycle.  This looks like an interesting bug fix for 3.7.

Well, now that I think about it, this is not even a *bug* fix since it's behavior that configparser had since 1997.

So that will have to go straight to 3.8.

What *actually* was changed in 3.2?

> What *actually* was changed in 3.2?

In terms of this issue, nothing.  That piece of documentation was put without proper testing, based purely on a comment that somebody put on issue12036.  My mistake.

New changeset 1d4a733cceee237f0850b7887c2945dee707da27 by Łukasz Langa (Chris Bradbury) in branch 'master':
bpo-33251: Prevent ConfigParser.items returning items present in vars. (#6446)
https://github.com/python/cpython/commit/1d4a733cceee237f0850b7887c2945dee707da27

New changeset e500839796c7fa43998e72edb77165872b9ce034 by Łukasz Langa (Chris Bradbury) in branch 'master':
bpo-33251: Update documentation to reflect change. (GH-6446) (#6583)
https://github.com/python/cpython/commit/e500839796c7fa43998e72edb77165872b9ce034