fix(tap): handle unset git config vars in taps

[gibfahn]

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cc/ @reitermarkus

Commits (oldest to newest)

3479d70 fix(tap): handle unset git config vars in taps

I'm not sure how/when this happened, but I have this in the
.git/config for some of my taps.

[homebrew]
	private =

And this breaks brew upgrade and brew tap-info <tap> since
#16811.

[MikeMcQuaid]

I cannot reproduce by adding

[homebrew]
	private = 

to a tap and running brew tap-info on that tap.

@gibfahn can you try to get a more minimal, step-by-step reproduction? Would rather not merge this as-is.

[reitermarkus]

The only place where a nil could come from seems to be GitHub.private_repo?. Can you check

brew ruby -e 'p GitHub.private_repo?("<your/homebrew-tap>")'

[reitermarkus]

Do you have HOMEBREW_NO_GITHUB_API set?

$ brew ruby -e 'p GitHub.private_repo?("reitermarkus/homebrew-tap")'
false

vs.

$ export HOMEBREW_NO_GITHUB_API=1
$ brew ruby -e 'p GitHub.private_repo?("reitermarkus/homebrew-tap")'
nil

[gibfahn]

Do you have HOMEBREW_NO_GITHUB_API set?

Oh yes, I guess that's the difference? Was trying to work out why I could reproduce it.