[rspec-users] Stub a class and instances

David Chelimsky dchelimsky at gmail.com
Mon Apr 5 08:48:44 EDT 2010

On Apr 4, 2010, at 11:21 PM, Marcelo de Moraes Serpa wrote:

> For example, I have this scenario where a Directory model will only save if it can connect to the LDAP server. In a test I'm writting, though, connecting to the LDAP server is not relevant, so I tried doing this:
>  context "LDAP is on" do
>         before(:each) do
>            Directory.stub!(:authenticate_user).and_return(@user).
>           @account.directory = Directory.make :ldap_on
>         end
> ...
> end
> However, the Directory.make fails (since the before_save ldap test fails, because authenticate_user can't connect to the LDAP server). The issue is that it stubs the method as a singleton method of Directory. 

That is how stubbing works in RSpec, and every other Ruby stubbing/mocking framework I know of. If you tell a class to stub a method, it stubs a class method. If you want to stub an instance method, you stub it directly on an instance. Mocha has an any_instance method, which RSpec doesn't have (yet), that allows you to say:


You can either switch to mocha and do that, or stub whatever creation mechanism is being used:

  directory = Directory.new
  account.directory = Directory.make :ldap_on

> One alternative is opening the Directory class and redefining the authenticate_user method, but I'd like to know if rSpec supports somehow stubing a class and let it stub instance too.

I don't think you'd want to stub the same method on the class and instance automatically. You might end up with false positives when one object calls a class method on an instance.


More information about the rspec-users mailing list