rspec_bisect

Brings “git bisect” powers to RSpec for your Ruby-on-Rails projects.
“git bisect”’s purpose is to find a specific commit which had broken something.
rspec_bisect purpose is to find one spec that causes other spec(s) to fail when they are runned together.

run example

Put bisect.rb in Rails.root/spec/ folder and run it like that:

#./spec/bisect.rb spec/**/*_spec.rb spec/controllers/spaces/tickets_controller_spec.rb
[.] rspec runner: ./script/spec
[.] target spec : spec/controllers/spaces/tickets_controller_spec.rb
[.] 123 candidate specs
[.] running   62 specs.. Done. ( 19s) (105/0/4) : target OK
[.] running   63 specs.. Done. ( 60s) (384/2/6) : target FAIL
[.] running   32 specs.. Done. ( 35s) (157/0/2) : target OK
[.] running   32 specs.. Done. ( 47s) (236/2/4) : target FAIL
[.] running   16 specs.. Done. ( 35s) (129/2/1) : target FAIL
[.] running    8 specs.. Done. ( 28s) (73/0)    : target OK
[.] running    9 specs.. Done. ( 22s) (65/2/1)  : target FAIL
[.] running    5 specs.. Done. ( 18s) (52/2/1)  : target FAIL
[.] running    3 specs.. Done. ( 17s) (33/0)    : target OK
[.] running    3 specs.. Done. ( 17s) (28/2/1)  : target FAIL
[.] running    2 specs.. Done. ( 17s) (27/2/1)  : target FAIL
[*] found matching spec: spec/models/mailman_spec.rb

fork() saves your time

Loading full Rails environment on each run is a pain.
So, using fork() in right place can save a lot of time.
Check out this example, and compare to a previous one:

#./spec/bisect.rb spec/**/*_spec.rb spec/controllers/spaces/tickets_controller_spec.rb --fork
[.] rspec runner: ./script/spec
[.] target spec : spec/controllers/spaces/tickets_controller_spec.rb
[.] 123 candidate specs
[.] preloading Rails environment..
[.] running   62 specs.. Done. (  9s) (105/0/4) : target OK
[.] running   63 specs.. Done. ( 49s) (384/2/6) : target FAIL
[.] running   32 specs.. Done. ( 21s) (157/1/2) : target OK
[.] running   32 specs.. Done. ( 34s) (236/3/4) : target FAIL
[.] running   16 specs.. Done. ( 24s) (129/3/1) : target FAIL
[.] running    8 specs.. Done. ( 20s) (73/1)    : target OK
[.] running    9 specs.. Done. (  9s) (65/3/1)  : target FAIL
[.] running    5 specs.. Done. (  8s) (52/3/1)  : target FAIL
[.] running    3 specs.. Done. (  4s) (33/1)    : target OK
[.] running    3 specs.. Done. (  8s) (28/3/1)  : target FAIL
[.] running    2 specs.. Done. (  7s) (27/3/1)  : target FAIL
[*] found matching spec: spec/models/mailman_spec.rb

First example took 315 seconds to run, second one only 193s. Considerable performance boost!

more

See all command-line options by running bisect.rb without any options or with --help.

Learn more at my technical blog.