Evaluate minitest 6.0.1 upgrade

[justin808]

Context

Dependabot PR #46 bumps minitest from 5.27.0 to 6.0.1. This is a major version bump.

Tasks

• Review minitest 6.0 changelog for breaking changes
• Run test suite with minitest 6 and fix any failures
• Close Dependabot PR Bump minitest from 5.27.0 to 6.0.1 #46 once done

Notes

Major version bump — may have deprecation removals or API changes. Test thoroughly.

[justin808]

Evaluation Complete

Result: Minitest 6.0 requires Rails 8.1+

Attempted upgrade — minitest 6.0.1 installs fine and activesupport >= 5.1 constraint is satisfied, but Rails 8.0.4's railties/lib/rails/test_unit/line_filtering.rb monkey-patches Runnable.run(reporter, options={}) with the minitest 5 signature. Minitest 6 changed this to run(klass, method_name, reporter), causing:

wrong number of arguments (given 3, expected 1..2) (ArgumentError)

Fix is in Rails 8.1+ — rails/rails#56202

Test code review (no issues found)

• No spec expectations on Object
• No minitest/mock usage
• No assert_send or assert_equal(nil, ...) patterns
• Standard Rails assertions only — will work fine once Rails is upgraded

Next steps

1. Upgrade to Rails 8.1+ first
2. Then upgrade minitest to ~> 6.0
3. Dependabot PR Bump minitest from 5.27.0 to 6.0.1 #46 closed with explanation

See PR #67 for the full evaluation.