Drop support for Django < 2.2 (incl. Python < 3.5) and clean up afterwards

[michael-k]

If you want to combine all the EOL drops in a single release, you should consider dropping support for Python 3.5 as well. It reaches its EOL on 2020-09-13 (in 3 weeks), see https://devguide.python.org/#status-of-python-branches. There won't be another EOL of Python or Django until Django 3.0 reaches its EOL in April 2021.

[codecov[bot]]

Codecov Report

Merging #187 into master will decrease coverage by 3.63%. The diff coverage is 94.87%.

@@            Coverage Diff             @@
##           master     #187      +/-   ##
==========================================
- Coverage   83.39%   79.76%   -3.64%     
==========================================
  Files          20       20              
  Lines        2506     2481      -25     
==========================================
- Hits         2090     1979     -111     
- Misses        416      502      +86     

Flag	Coverage Δ
#javascript	79.58% <ø> (ø)
#python	80.04% <94.87%> (-9.13%)	:arrow_down:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
nested_admin/nested.py	95.86% <89.47%> (-0.89%)	:arrow_down:
nested_admin/__init__.py	92.30% <100.00%> (-0.20%)	:arrow_down:
nested_admin/forms.py	100.00% <100.00%> (ø)
nested_admin/formsets.py	89.91% <100.00%> (-1.45%)	:arrow_down:
nested_admin/polymorphic.py	78.12% <100.00%> (-0.23%)	:arrow_down:
nested_admin/views.py	81.25% <100.00%> (ø)
nested_admin/compat.py	20.45% <0.00%> (-59.85%)	:arrow_down:
nested_admin/templatetags/nested_admin.py	80.90% <0.00%> (-1.82%)	:arrow_down:

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[fdintino]

We're currently in the process of upgrading to python 3 and the latest django LTS release for all of our django installs. It should be completed soon (some time in the next few months) but until then we won't drop support from django-nested-admin.

[michael-k]

Ping me when you're done and I'll rebase.

[ulgens]

@fdintino Any update there?

[fdintino]

@ulgens All of our systems will be upgraded to python 3.7+ and django 2.2 by this summer, if not sooner. The reason it's taking a while is that the upgrade is happening in tandem with a change to our hosting infrastructure.

[ulgens]

@fdintino I'm missing who is "we" in your comments but why not create sth like "legacy" or "python2" branch and use it instead of stopping development of the whole tool?

[fdintino]

Sorry, by "we" I meant "The Atlantic." I take your point, but I'm not sure I agree that a few if django.VERSION < (X, Y) conditional blocks and six functions has stopped development of django-nested-admin.

[ceelian]

Are there any plans to get this merged, or are there some open issues which I am not aware of in that PR. thx.

[lorddaedra]

Suggestions:

1. Support matrix:

• add support for Python 3.6-3.10
• add support for Django 2.2, 3.1 and 3.2
• drop support for Python < 3.6
• drop support for Django < 2.2 and 3.0
• provide support only for green-green combinations of Python and Django (drop support for any combinations "supported Django version + unsupported Python version" or "unsupported Django version + supported Python version")

2. Formatting:

There are many opinions about f-strings. For example, https://wemake-python-stylegui.de/en/latest/pages/usage/violations/consistency.html#wemake_python_styleguide.violations.consistency.FormattedStringViolation They forbid usage of f-strings at all.

I disagree with FormattedStringViolation and in same time I disagree with @ulgens about There are too many places that can be improved by the usage of f strings. too.

My opinion: use f-strings with caution.

[gaige]

Django 4.0 is now out, any chance of adding support as part of this?

1. The replacement of django.conf.urls.url (and recommendation to use django.urls.re_path() as it was just an alias) has been around since 2.0, so it should be safe to apply (see https://github.com/theatlantic/django-nested-admin/pull/205)
2. Add support for 4.0 in the test matrix

[lorddaedra]

I update my suggestions:

1. Support matrix: Django 2.2 LTS + Python 3.6, 3.7, 3.8 and 3.9 Django 3.2 LTS + Python 3.6, 3.7, 3.8, 3.9 and 3.10 Django 4.0 + Python 3.8, 3.9 and 3.10

So 12 combinations, 2 most wanted (I guess): Django 3.2 LTS + Python 3.10 and Django 4.0 + Python 3.10.

[fdintino]

I'll look into merging these pull requests sometime this week.

[ulgens]

@fdintino Any luck?

[codecov-commenter]

Codecov Report

Merging #187 (4c62da2) into master (2554f51) will decrease coverage by 0.46%. The diff coverage is n/a.

:exclamation: Current head 4c62da2 differs from pull request most recent head 55a07ee. Consider uploading reports for the commit 55a07ee to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #187      +/-   ##
==========================================
- Coverage   79.18%   78.71%   -0.47%     
==========================================
  Files          19        9      -10     
  Lines        2488     1480    -1008     
==========================================
- Hits         1970     1165     -805     
+ Misses        518      315     -203     

Flag	Coverage Δ
javascript	78.71% <ø> (-0.28%)	:arrow_down:
python	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...admin/static/nested_admin/src/nested-admin/grp$.js	50.00% <0.00%> (-50.00%)	:arrow_down:
nested_admin/__init__.py
nested_admin/forms.py
nested_admin/formsets.py
nested_admin/nested.py
nested_admin/polymorphic.py
nested_admin/views.py
nested_admin/templatetags/nested_admin.py
nested_admin/exceptions.py
nested_admin/urls.py
... and 1 more

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