Bad Requested Python version (X.Y) not installed output

[jurko-gospodnetic]

When running tox (at least on Windows) and there is and there is a test environment defined in the tox configuration file for which a suitable Python interpreter version is not installed on the system, tox output incudes stderr output like Requested Python version (X.Y) not installed.

The error described above occurs even when just running tox with the --help command-line option, and even if explicitly requesting a different test environment using the -e command-line option.

For example, when running tox --help with the current tox master (20215c1) with only Python 2.7 & 3.6 installed, I get the following output:

(venv) D:\Workplace\Open-source\Python tox>tox --help
Requested Python version (3.4) not installed
Requested Python version (3.5) not installed
usage: tox [--version] [-h] [--help-ini] [-v] [--showconfig] [-l] [-a]
           [-c CONFIGFILE] [-e envlist] [--notest] [--sdistonly]
           [--installpkg PATH] [--develop] [-i URL] [--pre] [-r]
           [--result-json PATH] [--hashseed SEED] [--force-dep REQ]
           [--sitepackages] [--alwayscopy] [--skip-missing-interpreters]
           [--workdir PATH]
           [args [args ...]]
...

[jurko-gospodnetic]

Pull request #686 added to address the issue.

[gaborbernat]

Resolved by #686