Fix testunit CI hang by requiring test-unit >= 3.7.4

[S-H-GAMELINKS]

The 3.3 testunit CI job was hanging for 6 hours and timing out.

Problem

test-unit 3.7.4 changed the TestSuite#run method signature

• 3.7.3: run(result, run_context: nil, &block)
• 3.7.4+: run(worker_context, &block)

test-queue's TestSuite subclass uses def run(*); super; end, which fails on 3.7.3 when test-unit internally calls run with 2 arguments:

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

The worker process crashes, but the master process keeps waiting indefinitely, causing the hang.

Reproduction

gem install test-unit -v 3.7.3
BUNDLE_GEMFILE=gemfiles/testunit.gemfile bundle exec testunit-queue ./test/examples/*_testunit.rb

gem install test-unit -v 3.7.5
BUNDLE_GEMFILE=gemfiles/testunit.gemfile bundle exec testunit-queue ./test/examples/*_testunit.rb

Solution

Pin test-unit to >= 3.7.4 in gemfiles/testunit.gemfile.

[koic]

Can you add a brief source code comment explaining the reason? For example:

Suggested change

	gem 'test-unit', '>= 3.7.4'
	# test-unit 3.7.4 changed `TestSuite#run` method signature.
	# Earlier versions cause ArgumentError in test-queue's TestSuite subclass,
	# crashing workers and causing the master process to hang indefinitely.
	gem 'test-unit', '>= 3.7.4'

[S-H-GAMELINKS]

Thanks for your review.
I've added a comment explaining why the test-unit version was selected.

[koic]

Thanks!