Keep support for prompt_toolkit 2

[meeuw]

Description

It turns out that Fedora 32 doesn't have prompt-toolkit 3 yet :-(

Seems we still support Prompt Toolkit 2 without any code changes (the tests don't fail on my system).

Checklist

• I've added this contribution to the changelog.rst.
• I've added my name to the AUTHORS file (or it's already there).

• I installed pre-commit hooks (pip install pre-commit && pre-commit install), and ran black on my code.
• Please squash merge this pull request (uncheck if you'd like us to merge as multiple commits)

[codecov-commenter]

Codecov Report

Merging #1197 into master will decrease coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1197      +/-   ##
==========================================
- Coverage   83.89%   83.85%   -0.04%     
==========================================
  Files          21       21              
  Lines        2552     2552              
==========================================
- Hits         2141     2140       -1     
- Misses        411      412       +1     

Impacted Files	Coverage Δ
pgcli/pgstyle.py	64.00% <ø> (ø)
pgcli/main.py	76.07% <0.00%> (-0.14%)	⬇️

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[meeuw]

Whoops thanks for checking this @laixintao that was my idea (to include pt 3). Fixed in 36e6047

[j-bennet]

@meeuw Did you verify that pgcli can work with both prompt_toolkit 2.x and 3.x? I thought they are not compatible.

[laixintao]

@meeuw Did you verify that pgcli can work with both prompt_toolkit 2.x and 3.x? I thought they are not compatible.

I think it's compatible, I didn't change any code while upgrading from 2.x: https://github.com/dbcli/pgcli/pull/1149/files , and I checked the changelog.

Can @jonathanslenders confirm?

[j-bennet]

You are right @laixintao , it looks like the only breaking changes are in get_event_loop and dialogs, and we're not using those calls in pgcli:

https://python-prompt-toolkit.readthedocs.io/en/stable/pages/upgrading/3.0.html

This is good.

[meeuw]

🎉 yes, I've checked that pgcli still works with pt-2. Thanks a lot for merging!