Expectations in a RSpec before filter

Last week I found a piece of code which put expectations (for example should_receive or the likes) in before filters in your spec file. I believe this is not correct in subtle ways.

• A before filter is meant to define the ‘world’ your RSpec is going to run in. Not to set expectations. These go into it blocks.
• Besides that, when putting expectations in a before filter, the expectation is needlessly checked ever it block. Imagine the expectation not being met. All of the sudden all your specs turn red. I’d rather see a specific spec fail so I immediately know where to look.

So I’m suggesting to put no expectations in your before filters and if you feel the urge to do so it probably needs it’s own it block.

An example of how it should be done:

describe "foo" do
    before do
        some_object.stub(:some_method).and_return(:some_value)
    end

    it "manipulates the object" do
        some_object.should_receive(:some_method).with(:some_argument)
        some_invocation
    end
end