[email protected]: make keg-only

[branchvincent]

• Have you followed the guidelines for contributing?
• Have you ensured that your commits follow the commit style guide?
• Have you checked that there aren't other open pull requests for the same formula update/change?
• Have you built your formula locally with brew install --build-from-source <formula>, where <formula> is the name of the formula you're submitting?
• Is your test running fine brew test <formula>, where <formula> is the name of the formula you're submitting?
• Does your build pass brew audit --strict <formula> (after doing brew install --build-from-source <formula>)? If this is a new formula, does it pass brew audit --new <formula>?

---

Closes #86520

#84626 (comment)

cc: @carlocab

[Bo98]

This should involve a revision bump or existing installations won't be made keg only.

[branchvincent]

does that imply this can't be a syntax-only pr?

[Bo98]

Revision bump means new bottles so it can’t be syntax-only, sorry. It’s important we migrate users or they will face conflicts if they attempt to install [email protected].

[Bo98]

link_overwrite can also be removed when made keg-only.

[Bo98]

Other adjustments to make, if I haven't missed anything:

-    # post_install happens after link
-    %W[pip3 wheel3 pip#{version.major_minor}].each do |e|
-      (HOMEBREW_PREFIX/"bin").install_symlink bin/e
-    end
-

   def caveats
     <<~EOS
       Python has been installed as
-        #{HOMEBREW_PREFIX}/bin/python3
+        #{opt_bin}/python3
 
       Unversioned symlinks `python`, `python-config`, `pip` etc. pointing to
       `python3`, `python3-config`, `pip3` etc., respectively, have been installed into
         #{opt_libexec}/bin
 
       You can install Python packages with
-        pip3 install <package>
+        #{opt_bin}/pip3 install <package>

[branchvincent]

happy to fix those, but CI will take several days correct? I was assuming we needed a quick fix, because we currently have [email protected] and [email protected] both installing as $(brew --prefix)/bin/python3.

if that's the case and I'm not misunderstanding, then perhaps we should first make [email protected] keg-only?

[carlocab]

If we want something quick we could add conflicts_with for now to produce a better error message until we can make this keg-only.

[branchvincent]

seems the last python migration went like this:

1. Add [email protected]+1 as keg-only in a single PR
2. Update one formula per PR to depends_on "[email protected]+1
3. Make [email protected]+1 the main python

if we're following that again, then we just missed making [email protected] keg-only, right? i think a PR to correct that should be quick

[carlocab]

seems the last python migration went like this:

1. Add [email protected]+1 as keg-only in a single PR
2. Update one formula per PR to depends_on "[email protected]+1
3. Make [email protected]+1 the main python

if we're following that again, then we just missed making [email protected] keg-only, right? i think a PR to correct that should be quick

Sounds good!

[Bo98]

but CI will take several days correct?

Well, one day maybe - not several.

Though I'm also fine with the 3.10 keg only approach for now.

[carlocab]

We also need to do [email protected]. Can be a separate PR.

Also, more changes might be needed here -- IIRC what we do with ensurepip here isn't done in the older Python formulae because it installs stuff directly into HOMEBREW_PREFIX (rather than into the formula prefix in HOMEBREW_CELLAR) so it breaks the formula being keg-only.

At least, I think that's what I found when I tried backporting the changes to [email protected]. I may have just done things wrong or am misremembering.

[Bo98]

Installing to /usr/local/lib/python3.9/site-packages is fine as our keg only formulae still symlink to there (intentionally). If ensurepip only touches that then it's fine, if not then it's worth looking to fix that.

[carlocab]

I think ensurepip installs a /usr/local/bin/pip (or pip3?).

[Bo98]

A quick test in the CI is to ask it to print the contents of HOMEBREW_PREFIX/bin at the end of postinstall (and might as well do python-tk at the same time since that'll be a couple more runs).

[branchvincent]

seems neither HOMEBREW_PREFIX/"bin/pip3" nor HOMEBREW_PREFIX/"bin/pip" get created

[carlocab]

Thanks @branchvincent!

[carlocab]

Actually, does this have OpenSSL 1.1 in its dep tree other than through here? If so we should use OpenSSL 3.0.

[Bo98]

We shouldn't use OpenSSL 3.0 until it or 1.1 is keg only, or we're just going to reintroduce the problem #86520 is having.

[Bo98]

Also that person was probably right in saying we should avoid anything too important while that old macOS build issue is still a thing.

[BrewTestBot]

@branchvincent has triggered a merge.