Rake tasks to run specs and tests in parallel, to use multiple CPUs and speedup test runtime.

Setup

For this fork (to be removed before pulling upstream):

script/plugin install git://github.com/jasonm/parallel_specs.git

For the upstream plugin:

script/plugin install git://github.com/grosser/parallel_specs.git

Add <%= ENV['TEST_ENV_NUMBER'] %> to the database name for the test environment in config/database.yml,
it is '' for process 1, and '2' for process 2.

test:
  adapter: mysql
  database: xxx_test<%= ENV['TEST_ENV_NUMBER'] %>
  username: root

For each environment, create the databases mysql -u root -> create database xxx_test2;

Run like hell :D

rake spec:parallel:prepare[2] #db:reset for each database

rake spec:parallel[1] --> 86 seconds
rake spec:parallel    --> 47 seconds (default = 2)
rake spec:parallel[4] --> 26 seconds
...

Example output

2 processes for 210 specs, ~ 105 specs per process
... test output ...

Results:
877 examples, 0 failures, 11 pending
843 examples, 0 failures, 1 pending

Took 29.925333 seconds

Test::Unit

To run Test::Unit tests, use the following task:

rake test:parallel

instead of

rake spec:parallel

This includes the ability to specify more than two parallel environments.

TIPS

• ./script/generate rspec if you are running rspec from gems (this plugin uses script/spec which may fail if rspec files are outdated)
• with zsh this would be rake "spec:parallel:prepare[3]"

TODO

• find out how many CPUs the user has here
• grab the 'xxx examples ..' line and display them after all tests have finished

Authors

inspired by pivotal labs

###Contributors

• Joakim Kolsjö -- joakim.kolsjo<$at$>gmail.com
• Jason Morrison -- jason.p.morrison<$at$>gmail.com

Michael Grosser
[email protected]
Hereby placed under public domain, do what you want, just do not hold me accountable...