Run every test in a fork to avoid pollution and get clean output per test. Forks are fast because they preload the test_helper + all fixtures.

Install

gem install forking_test_runner

forking-test-runner test
Running tests test/another_test.rb test/pollution_test.rb test/simple_test.rb
------ >>> test/another_test.rb
Run options: --seed 19151

# Running tests:

.

Finished tests in 0.002904s, 344.3526 tests/s, 344.3526 assertions/s.

1 tests, 1 assertions, 0 failures, 0 errors, 0 skips
------ <<< test/another_test.rb ---- OK

...

Results:
test/another_test.rb: OK
test/pollution_test.rb: OK
test/simple_test.rb: OK

9 assertions, 0 errors, 0 failures, 0 skips, 8 tests

Usage

Run it with individual files

forking-test-runner test/models/user_test.rb test/models/order_test.rb

Simple parallel execution on CI

forking-test-runner test --group 1 --groups 20

Make test groups take the same time

Record test runtime (on your CI, see other modes below)

forking-test-runner test --group 1 --groups 20 --record-runtime amend

Then download the runtime + commit it to your repo + run with runtime

forking-test-runner test --group 1 --groups 20 --runtime-log test/files/runtime.log

Only provide output from failed tests

forking-test-runner test --quiet

RSpec

Just add --rspec

Options

forking-test-runner folder [options]
    --rspec                      RSpec mode
    --helper                     Helper file to load before tests start
    --quiet                      Quiet
    --no-fixtures                Do not load fixtures
    --no-ar                      Disable ActiveRecord logic
    --merge-coverage             Merge base code coverage into indvidual files coverage, great for SingleCov
    --record-runtime=MODE        
      Record test runtime:
        simple = write to disk at --runtime-log)
        amend  = write from multiple remote workers via http://github.com/grosser/amend, needs TRAVIS_REPO_SLUG & TRAVIS_BUILD_NUMBER
    --runtime-log=FILE           File to store runtime log in or runtime.log
    --group=NUM                  What group this is (use with --groups / starts at 1)
    --groups=NUM                 How many groups there are in total (use with --group)
    --version                    Show version
    --help                       Show help