Tutorial :Can I override task :environment in test_helper.rb to test rake tasks?


I have a series of rake tasks in a Rakefile which I'd like to test as part of my specs etc. Each task is defined in the form:

task :do_somthing => :environment do    # Do something with the database here  end  

Where the :environment task sets up an ActiveRecord/DataMapper database connection and classes. I'm not using this as part of Rails but I have a series of tests which I like to run as part of BDD.

This snippet illustrates how I'm trying to test the rake tasks.

def setup    @rake = Rake::Application.new    Rake.application = @rake    load File.dirname(__FILE__) + '/../../tasks/do_something.rake'  end    should "import data" do    @rake["do_something"].invoke    assert something_in_the_database  end  

So my request for help - is it possible to over-ride the :environment task in my test_helper.rb file so I my rake testing interacts with the my test database, rather than production? I've tried redefining the task in the helper file, but this doesn't work.

Any help for a solution would be great, as I've been stuck on this for the past week.


My "solution" to a similar problem was to extract all the logic from my .rake files and create classes to perform the tasks, leaving just a one-line call in the rake file, which I felt confident in not testing too hard. The classes could then be tested pretty much normally.

I don't know how well this would stand up to a complex set of interdependent tasks that maintain some far-reaching state: probably not well, but then again that would most likely be an indication of some other design problem...

I'm curious to see if I've missed something better.

EDIT: There used to be a blog post here that (a) says the same thing and (b) says it better. Looks like he said it first, too.


I think you are looking for this line: require(File.join(RAILS_ROOT, 'config', 'environment')) it's exactly what you find in "task :environment" implementation

I use it to test my rake tasks using rspec


when you are running tests environment is that is being loaded is test.

so you are interacting with test database only.

So i dont see any reason to override your rake task in test_helper.rb

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