Modernize CI: Appraisal gem, Ruby 3.2-head, Rails 7.2-edge

[flavorjones]

Summary

• Introduce the Appraisal gem for managing Rails version testing (matching audits1984/console1984 patterns)
• Bump minimum supported Rails to 7.2, minimum Ruby to 3.2
• Replace RAILS_VERSION env var approach with BUNDLE_GEMFILE pointing at appraisal-generated gemfiles
• New CI matrix: Ruby 3.2, 3.3, 3.4, 4.0, head × Rails 7.2, 8.0, 8.1, edge
• Add health checks to MySQL/PostgreSQL service containers
• Upgrade actions/checkout from v3 to v4
• Remove dead version guards and compatibility shims from test and lib code

Test plan

• CI matrix passes for all Ruby × Rails combinations
• Verify exclude for Ruby 3.2 × rails_edge (Rails main requires Ruby >= 3.3)

🤖 Generated with Claude Code

[Copilot]

Pull request overview

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Updates the project’s Rails/Ruby compatibility and CI strategy by moving to Appraisal-managed Rails gemfiles and expanding the GitHub Actions matrix to cover newer Ruby/Rails combinations, while removing legacy compatibility code paths.

Changes:

• Replace RAILS_VERSION-driven installs with Appraisal + committed gemfiles/* and CI BUNDLE_GEMFILE.
• Raise minimum Rails runtime dependencies to >= 7.2 and simplify code/tests by removing older-version shims.
• Expand CI matrix and harden DB services with container health checks.

Reviewed changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
test/query_comments_test.rb	Removes legacy Rails/Minitest shims and simplifies controller rendering + socket config test path.
marginalia.gemspec	Raises runtime dependency floor to Rails components >= 7.2.
lib/marginalia/comment.rb	Drops pre-6.1 connection config branch; relies on db_config path only.
gemfiles/rails_7_2.gemfile	Adds Appraisal-generated gemfile for Rails 7.2 testing.
gemfiles/rails_8_0.gemfile	Adds Appraisal-generated gemfile for Rails 8.0 testing.
gemfiles/rails_8_1.gemfile	Adds Appraisal-generated gemfile for Rails 8.1 testing.
gemfiles/rails_edge.gemfile	Adds Appraisal-generated gemfile for Rails main/edge testing.
Gemfile	Moves base dependencies toward Appraisal-based workflows (adds appraisal, pins minitest).
Appraisals	Defines Rails version appraisals used to generate per-Rails gemfiles.
.gitignore	Ignores appraisal lockfiles under gemfiles/.
.github/workflows/ci.yml	Updates CI matrix, switches to BUNDLE_GEMFILE, adds DB container health checks, bumps checkout action.

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[Copilot]

The root Gemfile no longer declares rails (or railties), but the test suite requires rails/version and loads Rails components. Running bundle exec rake test:all locally with the default Gemfile will likely fail unless BUNDLE_GEMFILE is set to an appraisal gemfile. Consider adding a default Rails dependency back to Gemfile (e.g., the minimum supported Rails) or updating the test/dev workflow so the default bundle + rake path still works.

Suggested change

	gem "rails"

[Copilot]

This PR raises the minimum supported Rails/Ruby, but the gemspec doesn’t declare a required_ruby_version. Adding it helps Bundler fail fast on unsupported Rubies and keeps the published gem metadata accurate. Also consider aligning repo metadata/docs (e.g., .ruby-version and README support statements) with the new minimums so contributors don’t default to an unsupported Ruby/Rails.

Suggested change

	gem.license = "MIT"
	gem.license = "MIT"
	gem.required_ruby_version = ">= 3.1"

[Copilot]

db:reset calls rake tasks that shell out to mysql to create/drop the test DB. The mysql CLI defaults to a local UNIX socket when no host is provided, and it does not reliably honor MYSQL_HOST, so this can fail when the DB is provided by a GitHub Actions service container. Consider updating the DB reset/create logic to force TCP (e.g., pass -h 127.0.0.1/--protocol=tcp, and port if needed) or adjust the workflow to run DB setup inside the container network.

Suggested change

	run: bundle exec rake db:reset test:all
	run: MYSQL_HOST=127.0.0.1 MYSQL_TCP_PORT=3306 bundle exec rake db:reset test:all

[Copilot]

This test stubs pool.db_config.configuration_hash but doesn’t ensure the stub is removed if an assertion raises. Other tests in this file use ensure for cleanup; consider wrapping the stub/unstub in a begin/ensure (or using Mocha’s block form) so stubs don’t leak across tests on failure.

Suggested change

	pool.db_config.stubs(:configuration_hash).returns({:socket => "marginalia_socket"})
	Marginalia::Comment.components = [:socket]
	API::V1::PostsController.action(:driver_only).call(@env)
	assert_match %r{/\*socket:marginalia_socket}, @queries.first
	pool.db_config.unstub(:configuration_hash)
	begin
	pool.db_config.stubs(:configuration_hash).returns({ :socket => "marginalia_socket" })
	Marginalia::Comment.components = [:socket]
	API::V1::PostsController.action(:driver_only).call(@env)
	assert_match %r{/\*socket:marginalia_socket}, @queries.first
	ensure
	pool.db_config.unstub(:configuration_hash)
	end