Requirements cleanup

[asvetlov]

Less aggressive alternative that still uses Makefile instead of pre-commit hooks

[codecov]

Codecov Report

Merging #6238 (ea4d229) into master (b4f4c58) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #6238   +/-   ##
=======================================
  Coverage   93.30%   93.30%           
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  Files         103      103           
  Lines       30360    30360           
  Branches     2729     2729           
=======================================
  Hits        28326    28326           
  Misses       1857     1857           
  Partials      177      177           

Flag	Coverage Δ
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[asvetlov]

Hmm, all this exists to prevent long dependency installation time on CI, especially if dependencies are not cached previously.

There is an alternative approach based on the constraints file.

1. All requirement *.in files are converted back to plain txt.
2. constraints.in is added with a content that includes all *.txt file
3. constraints.txt is generated from constraints.in by pre-compile run.
4. in GitHub CI, pip install -r requirements/lint.txt is replaced with pip install -r requirements/lint.txt -c requiremments/constraints.txt
5. new workflow is added to regenerate constraints file on every dependabot commit and push it back into PR if necessary

Currently, dependabot looks on txt files only and ignores .in templates; this breaks our dependency auto-update system.
Also, pip-compile is not auto-applied. We have de-sync between txt and in files.

By the proposed change, dependabot should keep working, installation is reasonable fast, constraints are regenerated automatically.

[asvetlov]

Merging the PR, dependabot post-update part may require additional tuning -- will do it by a separate PR if needed.

[patchback]

Backport to 3.8: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply cc1a5b9 on top of patchback/backports/3.8/cc1a5b988cace9e0da7d0a42131387928b4cbbde/pr-6238

Backporting merged PR #6238 into master

1. Ensure you have a local repo clone of your fork. Unless you cloned it
   from the upstream, this would be your origin remote.
2. Make sure you have an upstream repo added as a remote too. In these
   instructions you'll refer to it by the name upstream. If you don't
   have it, here's how you can add it:

   $ git remote add upstream https://github.com/aio-libs/aiohttp.git

3. Ensure you have the latest copy of upstream and prepare a branch
   that will hold the backported code:

   $ git fetch upstream
   $ git checkout -b patchback/backports/3.8/cc1a5b988cace9e0da7d0a42131387928b4cbbde/pr-6238 upstream/3.8

4. Now, cherry-pick PR Requirements cleanup #6238 contents into that branch:

   $ git cherry-pick -x cc1a5b988cace9e0da7d0a42131387928b4cbbde

   If it'll yell at you with something like fatal: Commit cc1a5b988cace9e0da7d0a42131387928b4cbbde is a merge but no -m option was given., add -m 1 as follows intead:

   $ git cherry-pick -m1 -x cc1a5b988cace9e0da7d0a42131387928b4cbbde

5. At this point, you'll probably encounter some merge conflicts. You must
   resolve them in to preserve the patch from PR Requirements cleanup #6238 as close to the
   original as possible.
6. Push this branch to your fork on GitHub:

   $ git push origin patchback/backports/3.8/cc1a5b988cace9e0da7d0a42131387928b4cbbde/pr-6238

7. Create a PR, ensure that the CI is green. If it's not — update it so that
   the tests and any other checks pass. This is it!
   Now relax and wait for the maintainers to process your pull request
   when they have some cycles to do reviews. Don't worry — they'll tell you if
   any improvements are necessary when the time comes!

🤖 @patchback
I'm built with octomachinery and
my source is open — https://github.com/sanitizers/patchback-github-app.

[patchback]

Backport to 3.9: 💔 cherry-picking failed — conflicts found

❌ Failed to cleanly apply cc1a5b9 on top of patchback/backports/3.9/cc1a5b988cace9e0da7d0a42131387928b4cbbde/pr-6238

Backporting merged PR #6238 into master

1. Ensure you have a local repo clone of your fork. Unless you cloned it
   from the upstream, this would be your origin remote.
2. Make sure you have an upstream repo added as a remote too. In these
   instructions you'll refer to it by the name upstream. If you don't
   have it, here's how you can add it:

   $ git remote add upstream https://github.com/aio-libs/aiohttp.git

3. Ensure you have the latest copy of upstream and prepare a branch
   that will hold the backported code:

   $ git fetch upstream
   $ git checkout -b patchback/backports/3.9/cc1a5b988cace9e0da7d0a42131387928b4cbbde/pr-6238 upstream/3.9

4. Now, cherry-pick PR Requirements cleanup #6238 contents into that branch:

   $ git cherry-pick -x cc1a5b988cace9e0da7d0a42131387928b4cbbde

   If it'll yell at you with something like fatal: Commit cc1a5b988cace9e0da7d0a42131387928b4cbbde is a merge but no -m option was given., add -m 1 as follows intead:

   $ git cherry-pick -m1 -x cc1a5b988cace9e0da7d0a42131387928b4cbbde

5. At this point, you'll probably encounter some merge conflicts. You must
   resolve them in to preserve the patch from PR Requirements cleanup #6238 as close to the
   original as possible.
6. Push this branch to your fork on GitHub:

   $ git push origin patchback/backports/3.9/cc1a5b988cace9e0da7d0a42131387928b4cbbde/pr-6238

7. Create a PR, ensure that the CI is green. If it's not — update it so that
   the tests and any other checks pass. This is it!
   Now relax and wait for the maintainers to process your pull request
   when they have some cycles to do reviews. Don't worry — they'll tell you if
   any improvements are necessary when the time comes!

🤖 @patchback
I'm built with octomachinery and
my source is open — https://github.com/sanitizers/patchback-github-app.