Unexpected invocation :remove_method (mocha)

Question

I am trying to test my Smser class in a rails application, and trying to use mocha to stub the actual sending method only. I should mention also that this is my first attempt at mocking/stubbing.

When running the test, I get the failure unexpected invocation: :remove_method - which looks like what mocha called on my object, to stub the method. So I am not sure what to do.

Here are the relevant code snippets:

Smser class

# models/smser.rb
class Smser
  ...<truncated>...

  def self.instance
    @@instance ||= self.new
  end

  private

  # Need to stub this
  def twilio(args)
    @client.account.messages.create args
  end
end

Test

# test/models/smser.rb
test "should send sms" do
  Smser.instance.stubs(:twilio).with(from: '123', to: '234', body: 'Message body')
  # <- ... here we run something that should invoke 'twilio' on the Smser object
end

Test Output

unexpected invocation: 
  #<Smser:0x68e4940>.twilio(:from => '123', :to => :remove_method, :body => :twilio)

satisfied expectations:
- allowed any number of times, invoked once: 
  #<Smser:0x68e4940>.twilio(:from => '123', :to => '234', :body => 'Message body')

Any help is appreciated.

Answer 1

The error practically means that Mocha is expecting different invocation of the twilio method on the Smser class.

Instead of:

Smser.instance.stubs(:twilio).with(from: '123', to: '234', body: 'Message body')

it should be:

Smser.instance.stubs(:twilio).with(from: '123', to: '234', body: :twilio)

because, as the error states, the body isn't "Message body" but :twilio.

HTH