Creating instance of ActionMailer for testing

Hi all, I am writing an action mailer test and am trying to snatch contents of the @body hash provided for the template for testing. Specifically, my plan is to do something like:

FooMailer.class_eval do   attr_accessor :original_body   def render_message method, body     self.original_body = body     super method, body   end end

and then test that a FooMailer instance has its original_body setup correctly (together with to, from and other headers).

However, I noticed that ActionMailer::Base goes out of its way to prevent instantiating mailer objects. Why does it do that?

Thanks, Dmitry

PS I realize that usual approach is just use pattern matching for the resulting TMail body. However such method seems to strongly couple the test to the email body template (e.g. I may setup the body[:profile] but the email resulting body may only contain the @profile.name, so the test has to know that the template renders just the name and change if the template changes)

Email templates change very rarely on my project, so I don’t mind the usual approach of matching the body against a few patterns. And, it’s easy to do. Anyway, here’s an example spec of a mailer on my current project:

describe Mailer, “job application submitted” do

before(:each) do @user = stub(:full_name => “Jane Roe”, :email_address => “user@example.com”) @applicant = stub(:full_name => “john doe”, :user => @user) @assessment_url = “http://www.example.com@email = Mailer.create_job_application_submitted(@applicant, @assessment_url) end

it “addresses the email from the support address” do @email.from.should == [“support@wingnut.com”] end

it “addresses the email to the given user” do @email.to.should == [@user.email_address] end

it “sets the subject” do @email.subject.should == “#{@applicant.full_name.titleize} - Job application submitted” end

it “includes the applicant name in the body” do @email.body.should match(/#{@applicant.full_name.titleize}/) end

it “includes the applicant’s assessment link in the body” do @email.body.should match(/#{@assessment_url}/) end

end

Hope that helps somehow.

Also, the Rails Guides site has some content on testing mailers: http://guides.rails.info/testing_rails_applications.html#_testing_your_mailers .

Regards, Craig

Thanks for the reply! Your solution works, but it is pretty much same as just doing assert_matches. After some thinking I realized that I can just stub out the render_message of the ActionMailer::Base class:

context "Email body hash" do    setup do      @bar = Bar.create!      FooMailer.any_instance.stubs(:render_message).with { |template, body> @body_hash = body}.returns(:email_body)      @email = FooMailler.create_send_foo(@bar)    end

   should "contain key pair :bar => @bar" do      assert_equal @bar, @body_hash[:bar]    end end

And that seems to do the trick. I am still quite curious as to why ActionMailer::Base is so set against having instances, but at least it works.

Dmitry