Use HOMEBREW_CURL universally, including formulae

[Bo98]

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Currently when curl is used in formulae, the value set in HOMEBREW_CURL is completely discarded. That means brewed curl is currently never used in formula builds/tests where it may be necessary (HOMEBREW_FORCE_BREWED_CURL), and may be used when not wanted (e.g. HOMEBREW_CURL_PATH).

This changes curl to use the same shim strategy as git does.

This fixes test failures on Linux involving curl, as seen in https://github.com/Homebrew/homebrew-core/pull/86291/checks?check_run_id=3773393332 when paired with Homebrew/homebrew-test-bot#671, unblocking a step towards fixing curl on older macOS.

[BrewTestBot]

Review period skipped due to critical label.

[Bo98]

@carlocab This should also cover Homebrew/homebrew-core#86257 (comment).

[Bo98]

Thanks both. I'd normally give longer review time for this, but it is absence of it is making CI fail just now for the nghttp2 PR - which is a part of whole fixing older macOS versions stuff.

I'll merge this now but will respond to feedback while the nghttp2 PR is running.

[Rylan12]

I know it's already merged but ✅ from me as well

[MikeMcQuaid]

Makes sense to me!

[thewilsonator]

I think this PR is the cause of some very strange issues we are experiencing in CI:
https://cirrus-ci.com/task/5219352065605632?logs=install_prerequisites#L95

in particular recent runs give

$ brew update-reset
==> Fetching /usr/local/Homebrew...
From https://github.com/Homebrew/brew
   OLD-SHA.. 28e4c9c  master     -> origin/master
 * [new tag]             2.7.2      -> 2.7.2
 * ... [lots off tags]...
 
==> Resetting /usr/local/Homebrew...
Switched to and reset branch 'master'
Branch 'master' set up to track remote branch 'master' from 'origin'.
Your branch is up to date with 'origin/master'.

## N.B. git HEAD _is_ 28e4c9c here

==> Fetching /usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask...
/usr/local/Homebrew/Library/Homebrew/brew.sh: line 102: /usr/local/Homebrew/Library/Homebrew/shims/scm/git: No such file or directory
/usr/local/Homebrew/Library/Homebrew/brew.sh: line 102: /usr/local/Homebrew/Library/Homebrew/shims/scm/git: No such file or directory
==> Resetting /usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask...
/usr/local/Homebrew/Library/Homebrew/brew.sh: line 102: /usr/local/Homebrew/Library/Homebrew/shims/scm/git: No such file or directory
/usr/local/Homebrew/Library/Homebrew/brew.sh: line 102: /usr/local/Homebrew/Library/Homebrew/shims/scm/git: No such file or directory

## same output for Taps "homebrew-cask-versions", "homebrew-core" and  "robotsandpencils/homebrew-made"

$ brew install gnupg
Error: gnupg: Calling `sha256 "digest" => :tag` in a bottle block is disabled! Use `brew style --fix` on the formula to update the style or use `sha256 tag: "digest"` instead.
Please report this issue to the homebrew/core tap (not Homebrew/brew or Homebrew/core), or even better, submit a PR to fix it:
  /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core/Formula/gnupg.rb:14

I can confirm line 102 of /usr/local/Homebrew/Library/Homebrew/brew.sh is a comment as it is in 28e4c9c and the git() function's path is Homebrew/shims/shared/git not Homebrew/shims/scm/git, I have no idea were the latter is coming from.

Any ideas?

[carlocab]

You have an old version of the gnupg formula getting picked up somewhere for some reason. Doesn’t seem related to this PR.

[thewilsonator]

It seems to me like the Fetching/Resetting of homebrew-core in brew update-reset is failing to execute properly due to missing git-shim. Our pipelines started failing yesterday, which is about when this PR was pulled.

[thewilsonator]

...and it seems to have been fixed by running brew update-reset twice?!??!??!! Oh well, this can serve as a note to any other unfortunate people who run into this.

[Bo98]

That seems like a bug with update-reset specifically where it doesn't reload itself after updating brew. I'm working on a fix.

[thewilsonator]

Thanks! If you could ping me on that PR when you open it that would be great.

[carlocab]

Fixed in #12186. Thanks for the report, @thewilsonator.