Fantaskspec

Makes it easy to test your Rake tasks with RSpec.

Installation

Add this line to your application's Gemfile:

gem "fantaskspec"

And then execute:

$ bundle

Then whereever you're configuring RSpec (spec_helper, rails_helper, whatever):

RSpec.configure do |config|
  # ...
  config.infer_rake_task_specs_from_file_location!
  # ...
end

That will make it so that specs in spec/lib/tasks and spec/tasks will automatically have a type of :rake (unless you override it).

Loading your Rake tasks

This gem doesn't load your Rake tasks for you, that's something you have to do. If you're using Rails, just add Rails.application.load_tasks to your rails_helper.rb. If you're not using Rails, just require the files you need.

Usage

Given a task that looks like this:

desc "Some rake task"
task some_task: :environment do
  puts "I don't do much."
end

We can test it like this:

require "spec_helper"

RSpec.describe "some_task" do
  it { is_expected.to depend_on(:environment) }

  it "executes some code" do
    expect(subject.execute).to eq(task.execute)
  end

  context "some sort of context" do
    it "still uses 'some_task' as the name of the task" do
      expect(task_name).to eq("some_task")
      expect(task_name).to eq(subject.name)
    end
  end
end

Here subject and task are both our Rake task called some_task. Fantaskspec gives us a handy depend_on matcher so we can ensure are dependencies are correct.

Here we're assuming we've called config.infer_rake_task_specs_from_file_location! in our RSpec.configure block so we don't need to specify type: :rake in any of our example groups as long as the test is located at spec/tasks or spec/lib/tasks.

We also have access to task_name, which is just the Fantaskspec's best guess at the name of the task we're specifying is, based on the description string we pass to describe or context.

Rake testing gotchas

There are 2 ways to get your Rake task's code to execute: by calling either execute or invoke on the task (or subject). execute will execute the Rake task but none of its dependencies. invoke will execute the task and dependencies, but the task and its dependencies will be disabled unless you call reenable on all of them. If you stick with `execute you probaly won't have any problems.

Contributing

1. Fork it
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request