Ensure method is called once during a test case

[Sven Dahlstrand]

Hello,

I want to test the UserObserver and make sure that
deliver_welcome_email is called when a user is saved.

class UserObserver < ActiveRecord::Observer
def after_create(user)
Mailer.deliver_welcome_email(user)
end
end

Here is my test case:

class UserObserverTest < ActiveSupport::TestCase
should 'should send welcome email when saved' do
user = Factory.build :user
Mailer.expects(:deliver_welcome_email).with(user)
user.save
end
end

Users are created in other tests as well and therefore
Mailer.deliver_welcome_email is called more than once and the test
fails. Is there a way to make sure that the method is called only once
during this particular test?

[James Mead]

2009/10/23 Sven Dahlstrand <sven.da...@gmail.com>:

I'm a little unclear what the problem is. Which test is failing? And
what is the error message?

An expectation in one test should have no influence on behaviour in
other tests. The expectation you have declared in the following line
already requires the 'deliver_welcome_email' to be called *exactly*
once :-

Mailer.expects(:deliver_welcome_email).with(user)

Although you could make it more explicit by using 'once' :-

Mailer.expects(:deliver_welcome_email).once.with(user)

Cheers, James.