f2a4941a23 (master): [ruby/rubygems] Prevent test git commands from mutating the checkout's own git config

[Hiroshi SHIBATA]

Hiroshi SHIBATA 2026-08-04 02:31:39 +0000 (Tue, 04 Aug 2026)

New Revision: f2a4941a23

https://github.com/ruby/ruby/commit/f2a4941a23

Log:
[ruby/rubygems] Prevent test git commands from mutating the checkout's own git config

When a fixture directory has no .git, git repository discovery walks up
into the checkout itself, and a fixture `git config user.email` lands
in the checkout's shared .git/config, polluting the author identity of
subsequent commits in every worktree. Set GIT_CEILING_DIRECTORIES so
discovery can never escape tmp/, make the spec git helper refuse local
config writes outside tmp/, and fix a show_spec setup line that
silently skipped `git init` because sys_exec does not go through a
shell. The rubygems test helper gets the same ceiling since its tmp
also lives inside the checkout by default.

https://github.com/ruby/rubygems/commit/4a49cfd2b3

Co-Authored-By: Claude Fable 5 <nor...@anthropic.com>

Modified files:
spec/bundler/commands/show_spec.rb
spec/bundler/spec_helper.rb
spec/bundler/support/subprocess.rb
test/rubygems/helper.rb