Add an exception at install for python < 3.6.2

[Pierre-Sassoulas]

Description

Type of Changes

	Type
✓	🐛 Bug fix
✓	📜 Docs

Related Issue

See pylint-dev/pylint#5065 and pylint-dev/pylint#5250

[cdce8p]

Looks good! It does even make sense to do it in 2.9.0. Pylint 2.11.1 has a limit for astroid <2.9.0 and the warning there is only included in 2.12.0.

[DanielNoord]

Should probably update this as well:
https://github.com/PyCQA/astroid/blob/935ff12e0d65899d3d48d1c7be9cbeeb1d9e6089/setup.cfg#L44

[Pierre-Sassoulas]

Should probably update this as well:

That's the tricky part, if we do that python users 3.6.0 will download 2.8.6 which is broken. So we're making our own error asking them to download astroid 2.6.6 before changing this value. (Same reasoning than with pylint 2.12.0 / 2.12.1)

[cdce8p]

Should probably update this as well:

https://github.com/PyCQA/astroid/blob/935ff12e0d65899d3d48d1c7be9cbeeb1d9e6089/setup.cfg#L44

No. We want this version to still be installable on 3.6 otherwise users would need see the error. That's also how we do it in pylint.

Something else I just realized, do we need this at all? AFAIK we don't have anything in astroid that breaks with Python 3.6.0.

[Pierre-Sassoulas]

do we need this at all? AFAIK we don't have anything in astroid that breaks with Python 3.6.0.

Well no-one complained yet 😄 To be fair I don't know exactly that's why I chose 2.6.6 (the astroid for thae last working pylint). I think @DanielNoord was upgrading the typing everywhere like a machine (edit : this is a compliment, I did not mean to imply 'mindelessly', sorry Daniel, thank you for doing so much for the typing 😄 ) so the probability of astroid being broken was high in my mind.

[cdce8p]

do we need this at all? AFAIK we don't have anything in astroid that breaks with Python 3.6.0.

Well no-one complained yet 😄 To be fair I don't know exactly that's why I chose 2.6.6 (the astroid for thae last working pylint). I think @DanielNoord was upgrading the typing everywhere like a machine so the probability of astroid being broken was high in my mind.

Typing itself isn't really a problem. The main issue in pylint is typing.NamedTuple that has some incompatibilities.

We should probably still update the min Python version to 3.6.2 but aside from that I don't think we need to do anything else.

[cdce8p]

We should probably still update the min Python version to 3.6.2 but aside from that I don't think we need to do anything else.

We could do this for astroid 2.9.0 as this will require pylint 2.12.0.

[cdce8p]

We should probably still update the min Python version to 3.6.2 but aside from that I don't think we need to do anything else.

We could do this for astroid 2.9.0 as this will require pylint 2.12.0.

Edit: If we require 3.6.2 now, the pip install will fail for pylint 2.12.0 and users will never see the exception message.

[Pierre-Sassoulas]

Plus, if astroid is still compatible with 3.6.0 / 3.6.1 let's close this issue altogether ?

[cdce8p]

Plus, if astroid is still compatible with 3.6.0 / 3.6.1 let's close this issue altogether ?

Yes! I've opened #1269 as a followup, when it's time to require Python 3.6.2.