Question

In this video from GoGaRuCo 2011, Corey Haines shows some techniques for making Rails test suites much faster. I would summarize it as follows:

• Put as much of your code as possible outside the Rails app, into other modules and classes
• Test those separately, without the overhead of loading up Rails
• Use them from within your Rails app

There were a couple of things I didn’t understand, though.

• He alternates between running tests with rspec and spn or spna (for example, at about 3:50). Is spn a commonly-known tool?
• In his tests for non-Rails classes and modules, he includes the module or class being tested, but I don’t see him including anything like spec_helper. How does he have Rspec available?

Answer 1

Sorry about the confusion. spn and spna are aliases I have that add my non-rails code to rspec’s load path. There isn’t anything special about them, other than adding a -I path_to_code on the command-line.

These days, I add something like this to my .rspec file:

-I app/mercury_app

Then I can do simple require 'object_name' at the top of my specs.

As for not including spec_helper: that is true, I don’t. When you execute your spec file with rspec <path_to_spec_file>, it gets interpreted, so you don’t need to require rspec explicitly.

For my db specs these days, I also have built an active_record_spec_helper which requires active_record, establishes a connection to the test database, and sets up database_cleaner; this allows me to simply require my model at the top of my spec file. This way, I can test the AR code against the db without having to load up my whole app.

A client I am working at where we are using these techniques is interested in supporting some blog posts about this, so hopefully they will start coming out towards the middle of June.