brew.rb: tell users to fix head issues with inreplace

[SMillerDev]

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WIP to ensure not only build command failures tell users of --HEAD to make a pull request

[BrewTestBot]

Review period will end on 2022-08-02 at 00:00:00 UTC.

[MikeMcQuaid]

Good idea 👍🏻

[Bo98]

Not convinced on making a parent FormulaError considering inreplace is not formula specific (it's used in bump-cask-pr etc. too).

Probably best to keep the error as it was and either:

• just add a generic object variable, or;
• have Formula-specific inreplace and inreplace_pairs methods which call super but catches the error and converts it to a BuildError or something similar. This would allow a lot of BuildError-specific logic to be reused and also does not affect how errors are handled in non-formula contexts.

[carlocab]

Yea, catching the inreplace error throwing a BuildError seems much nicer.

[SMillerDev]

And that's why it was a draft, thanks @Bo98. I'll check that later

[BrewTestBot]

Review period ended.

[SMillerDev]

A lot later, but it's done now.

[Bo98]

Fantastic. This is exactly how I hoped it would look.

[MikeMcQuaid]

Tiny style suggestion but: looks good to me!

[bayandin]

It looks like something went wrong, see Homebrew/homebrew-core#107575:

There's no error in the install block, but a problem with inreplace appears in ==> ENV block

 ==> ENV
  /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/build_environment.rb:60:in `keys': undefined method `keys' for nil:NilClass (NoMethodError)
  	from /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/build_environment.rb:65:in `dump'
  	from /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/exceptions.rb:505:in `dump'
  	from /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/brew.rb:148:in `rescue in <main>'
  	from /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/brew.rb:136:in `<main>'
  /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:2222:in `rescue in inreplace': Failed executing: inreplace configure (BuildError)
  	from /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/formula.rb:2219:in `inreplace'
  	from /home/linuxbrew/.linuxbrew/Homebrew/Library/Taps/homebrew/homebrew-core/Formula/nvc.rb:44:in `install'

https://github.com/Homebrew/homebrew-core/runs/7729673651?check_suite_focus=true#step:7:93