Ruby-on-rails – RSpec: Expecting a message multiple times but with differing parameters

rspecrubyruby-on-rails

I currently have some expectations set up on a mock with consecutive calls:

The spec:

@my_mock = mock("a_mock")
@options1 = {:some => "option"}
@options2 = {:some_other => "option"}
@first_param = mock("first_param")

@my_mock.should_receive(:a_message).with(@first_param, @options1)
@my_mock.should_receive(:a_message).with(@first_param, @options2)

However, i get the following:

Mock "a_mock" received :a_message with unexpected arguments
  expected: (#<Spec::Mocks::Mock:0x81b8ca3c @name="first_param"{:some => "option"})
   got: (#<Spec::Mocks::Mock:0x81b8ca3c @name="first_param">, {:some_other => "option"})

When I debug this, the first expectation IS getting called. Do I have to specify anything else before I can expect consecutive calls with the same message but differing parameters?

Best Answer

Try creating your mock as a null object to ignore extra method calls. Each of your expectations will still have to be met, but they won't step on each other.

@my_mock = mock("a_mock").as_null_object

This follows the Null Object pattern, in which any extraneous messages are just ignored. It is useful with mocks when you want to make sure a method gets called with certain parameters, but you don't care if it is called with other parameters or if any other methods get called.

Related Solutions

Ruby-on-rails – How to add multiple should_receive expectations on an object using RSpec

Multiple expectations are not a problem at all. What you're running into are ordering problems, given your specific args on unordered expectations. Check this page for details on ordering expectations.

The short story is that you should add .ordered to the end of each of your expectations.

R – Specing a manual call to valid

I'm not seeing mock_user. Here's a shot at it:

describe "POST validate" do
  it "retrieves the user based on the past in username" do
    mock_errors = mock("errors")
    mock_user = mock("user")
    mock_user.stub!(:errors).and_return([mock_errors])
    mock_errors.stub!(:[]).and_return(nil)
    User.should_receive(:new).with({'username'=>"UserName"}).and_return(mock_user)
    mock_user.should_receive(:valid?).and_return(true)
    mock_errors.should_receive(:[]).with("username").and_return(ActiveRecord::Errors.new({}))
    put :validate, :field=>'username', :value=>'UserName'      
    response.should == ""
  end
end

The key is that you need your User mock to respond to the errors method by returning either an empty hash or a hash of fieldname/errors. An alternative to this is to use one of the fixture replacement tools. I'm using machinist right now, which might reduce this whole thing to:

describe "POST validate" do
  it "retrieves the user based on the past in username" do
    @user = User.make{'username'=>"UserName"}
    @user.should_receive(:valid?).and_return(true)
    @user.errors.should_receive(:[]).with("username").and_return(ActiveRecord::Errors.new({}))
    put :validate, :field=>'username', :value=>'UserName'      
    response.should == ""
  end
end

Best Answer

Related Solutions

Ruby-on-rails – How to add multiple should_receive expectations on an object using RSpec

R – Specing a manual call to valid

Related Topic