TypeError: RSpec::Mocks::Mock#to_hash should return Hash

[lucasrenan]

controller

def create
  @city = City.new(params[:city])

  respond_with do |format|
    if @city.save
      format.html { redirect_to(admin_city_path(@city), :notice => 'City was successfully created.') }
    else
      format.html { render :action => "new" }
    end
  end
end

spec

def mock_city(stubs={})
  @mock_city ||= mock_model(City, stubs).as_null_object
end

describe "with valid params" do
  it "assigns a newly created city as @city" do
    City.stub(:new).with({'these' => 'params'}) { mock_city(:save => true) }
    post :create, :city => {'these' => 'params'}
    assigns(:city).should be(mock_city)
  end

  it "redirects to the created city" do
    City.stub(:new) { mock_city(:save => true) }
    post :create, :city => {}
    response.should redirect_to(city_url(mock_city))
  end
end

The problem seems to be with:
admin_city_path(@city)

Resulting in this error msg:
TypeError: RSpec::Mocks::Mock#to_hash should return Hash

[justinko]

What does mock_city do? Can you paste that code?

[lucasrenan]

I updated the issue, see the mock_city method above. (it was generated by scaffold)
My app uses CouchRest Model as orm, I tried with Mongoid and specs are running with no problems.

[justinko]

hmmm this same error was also reported here:

http://groups.google.com/group/rspec/browse_thread/thread/3155f6a90641208c/d8dc87a134b09fd1?lnk=gst&q=%23to_hash#d8dc87a134b09fd1

[myronmarston]

Can you paste a backtrace?

[lucasrenan]

exactly the same error

[alindeman]

It seems that something is calling #to_hash ... maybe something within the ORM?

Because you've created a mock with #as_null_object, the mock will return self because you haven't explicitly stubbed it out.

A backtrace should help figure out what part of the system is calling #to_hash.

[alindeman]

Another thing you could do is remove the #as_null_object bit so the mock will immediately raise an error when a method it doesn't recognize is called (in this case, #to_hash).

[lucasrenan]

backtrace:

rake aborted!
ruby -S bundle exec rspec ./spec/controllers/admin/cities_controller_spec.rb failed
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@ozzieboard/gems/rspec-core-2.5.1/lib/rspec/core/rake_task.rb:139:in 'initialize'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:1112:in 'verbose'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@ozzieboard/gems/rspec-core-2.5.1/lib/rspec/core/rake_task.rb:131:in 'send'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@ozzieboard/gems/rspec-core-2.5.1/lib/rspec/core/rake_task.rb:131:in 'initialize'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:636:in 'call'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:636:in 'execute'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:631:in 'each'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:631:in 'execute'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:597:in 'invoke_with_call_chain'
/Users/lucasrenan/.rvm/rubies/ruby-1.8.7-p174/lib/ruby/1.8/monitor.rb:242:in 'synchronize'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:590:in 'invoke_with_call_chain'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:583:in 'invoke'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:2051:in 'invoke_task'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:2029:in 'top_level'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:2029:in 'each'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:2029:in 'top_level'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:2068:in 'standard_exception_handling'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:2023:in 'top_level'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:2001:in 'run'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:2068:in 'standard_exception_handling'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/lib/rake.rb:1998:in 'run'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/gems/rake-0.8.7/bin/rake:31
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/bin/rake:19:in 'load'
/Users/lucasrenan/.rvm/gems/ruby-1.8.7-p174@global/bin/rake:19

[lucasrenan]

I removed #as_null_object then:

Failure/Error: post :create, :city => {'name' => 'sao paulo'} Mock "City_1005" received unexpected message :extractable_options? with (no args)

[dchelimsky]

mock_model (part of rspec-rails, not rspec-mocks) supports code that interacts with a model via the ActiveModel API. The problem with satisfying general methods like to_hash is the question: what should be in the hash that it returns that would satisfy all potential uses?

Once as_null_object is removed, we see a call to extractable_options? which is not an ActiveModel method (or a core Ruby method), so mock_model should not be expected to support it.

I'm going to close this as I think supporting this is definitely out of scope for rspec-mocks and probably even out of scope of rspec-rails. If you want to continue the conversation in terms of what mock_model should or should not support, please submit a new issue to https://github.com/rspec/rspec-rails/issues.