Each `brew upgrade`/`reinstall` writes `credential.helper` to `~/.gitconfig` even when already configured

[skkzsh]

Problem

Each brew upgrade or brew reinstall writes credential.helper entries to ~/.gitconfig,
even when git-credential-manager is already set as the credential.helper elsewhere — for example via an [include]d file — resulting in duplicate entries.

Steps to reproduce

1. Set up ~/.gitconfig:

   [include]
       path = .gitconfig.d/manager.gitconfig

2. Set up .gitconfig.d/manager.gitconfig with the git-credential-manager settings:

   [credential]
       helper =
       helper = /usr/local/share/gcm-core/git-credential-manager
   [credential "https://dev.azure.com"]
       useHttpPath = true

3. Confirm the credential.helper is resolved:
   (EDIT)

   $ git config --show-origin credential.helper
   file:/Users/skkzsh/.gitconfig.d/manager.gitconfig	/usr/local/share/gcm-core/git-credential-manager

4. Run brew upgrade --cask git-credential-manager or brew reinstall --cask git-credential-manager
5. Inspect ~/.gitconfig

Expected vs Actual behavior

Expected

~/.gitconfig should remain unchanged.

Actual

The following duplicate entries are written to ~/.gitconfig:

[credential]
    helper =
    helper = /usr/local/share/gcm-core/git-credential-manager

Note

[credential "https://dev.azure.com"] useHttpPath = true is correctly detected and not duplicated.

Version

$ git credential-manager --version
2.8.0+d5e8a3442d48cc5efe7014e093e44242c0bd395f

$ git --version
git version 2.54.0

Related

• git-credential-manager adds credential.helper to git config even if it's already configured #1337

[becm]

Also: #2328; the applied strategy to read update scoped settings is broken before Git 2.54.
Fix might start by adding --includes to the call and restore inclusion behavior
(default differs between scoped and non-scoped query).

[becm]

@skkzsh can you check if there is another valid match for /usr/local/share/gcm-core/git-credential-manager with
git config get --all --show-origin credential.helper
(e.g. on system level)?

Normally with GCM 2.8.0/Git 2.54, the new config cache is used, which should process includes correctly.
But there is a inconsistency in config detection (first/last index) leading to false identification.

[skkzsh]

@becm Thanks for looking into this.

Before upgrade/reinstall:

$ git config get --all --show-origin credential.helper
file:/opt/homebrew/etc/gitconfig    osxkeychain
file:/Users/skkzsh/.gitconfig.d/manager.gitconfig
file:/Users/skkzsh/.gitconfig.d/manager.gitconfig   /usr/local/share/gcm-core/git-credential-manager

After upgrade/reinstall:

$ git config get --all --show-origin credential.helper
file:/opt/homebrew/etc/gitconfig    osxkeychain
file:/Users/skkzsh/.gitconfig.d/manager.gitconfig
file:/Users/skkzsh/.gitconfig.d/manager.gitconfig   /usr/local/share/gcm-core/git-credential-manager
file:/Users/skkzsh/.gitconfig
file:/Users/skkzsh/.gitconfig   /usr/local/share/gcm-core/git-credential-manager

I also corrected the output in step 3 of the "Steps to reproduce", as there was a copy/paste error.

[becm]

@skkzsh the (I hope) underlying code for

/usr/local/share/gcm-core/git-credential-manager configure

does the right thing in my tests (when indeed using Git 2.54).

Not sure if the environment within the sudo call interferes with PATH settings, so an older Git version is used?

[skkzsh]

@becm I can confirm that running git-credential-manager configure manually does not cause the duplicate entry — only brew upgrade/reinstall does.
Since brew upgrade/reinstall invokes a sudo call internally, it might be referencing /usr/bin/git instead of the Homebrew-installed one.

log:

$ where git
/opt/homebrew/bin/git
/usr/bin/git
$ git --version
git version 2.54.0
$ /usr/bin/git --version
git version 2.50.1 (Apple Git-155)

$ brew reinstall --cask git-credential-manager
(...snip...)
==> Installing Cask git-credential-manager
==> Running installer for git-credential-manager with `sudo` (which may request your password)...
(...snip...)

[becm]

@skkzsh thanks, that gives me at least some hope that proper include handling for pre-Git-2.54 should fix this. ☺