Rspec controller test hanging - testing

Question

Here is my controller test ("spec/controllers/api/tasks_controller_spec.rb")
require 'spec_helper'
describe Api::TasksController do
before :each do
#quadros = create :cat
#task = Task.new(:content => "Example task for #api")
#quadros.add_task(#task)
end
describe "GET index" do
it "returns a list of all user's tasks" do
get :index, :format => 'json'
expect(response).to eq(User.first.all_tasks)
end
end
end
Here is my Api::BaseController
class Api::BaseController < ApplicationController
respond_to :json
skip_before_filter :authenticate_user!
end
And Api::TasksController
class Api::TasksController < Api::BaseController
def index
#tasks = User.first.all_tasks
respond_with #tasks.to_json
end
end
My other test run fine.
When I run the api test, it executes the before block, makes the request as json, and then hangs on this query:
Processing by Api::TasksController#index as JSON
User Load (0.3ms) SELECT `users`.* FROM `users` LIMIT 1
Tag Load (0.3ms) SELECT `tags`.* FROM `tags` WHERE (user_id = 418 AND parent_tag_id IS NOT NULL)
Tag Load (0.2ms) SELECT `tags`.* FROM `tags` WHERE `tags`.`id` IN (NULL)
Tag Load (0.3ms) SELECT `tags`.* FROM `tags` WHERE (user_id = 418 AND parent_tag_id IS NULL)
Task Load (0.7ms) SELECT tasks.* FROM `tasks` JOIN tag_tasks on tasks.id = tag_tasks.task_id WHERE (tag_tasks.tag_id IN (301) OR creator_id = 418) GROUP BY tasks.id ORDER BY tasks.created_at DESC
Completed 200 OK in 99ms (Views: 0.1ms | ActiveRecord: 0.0ms)
User Load (0.3ms) SELECT `users`.* FROM `users` LIMIT 1
Tag Load (0.2ms) SELECT `tags`.* FROM `tags` WHERE (user_id = 418 AND parent_tag_id IS NOT NULL)
Tag Load (0.2ms) SELECT `tags`.* FROM `tags` WHERE `tags`.`id` IN (NULL)
Tag Load (0.2ms) SELECT `tags`.* FROM `tags` WHERE (user_id = 418 AND parent_tag_id IS NULL)
Task Load (0.7ms) SELECT tasks.* FROM `tasks` JOIN tag_tasks on tasks.id = tag_tasks.task_id WHERE (tag_tasks.tag_id IN (301) OR creator_id = 418) GROUP BY tasks.id ORDER BY tasks.created_at DESC
Where it will just sit forever.
Any ideas why this might be happening?

Answer 1

I've come across a similar issue, and it appears the problem is with your expectation line:
expect(response).to eq(User.first.all_tasks)
This is not how RSpec wants you to test the response body. Notice that in the docs, specialized matchers are used instead of the equality matcher:
expect(response).to render_template("index")
So the response object, which is an ActionController::TestResponse, is meant to be queried about what happened, not what the response body was. So your test should be something like:
expect(JSON.parse(response.body)).to eq(User.first.all_tasks)
(Note that the response body is a string.)
As for the explanation of why the test hangs—instead of outright failing—it appears that this block of code (lib/rspec/expectations/fail_with.rb:22 in the rspec-expectations gem version 2.14.0) is the culprit:
if actual && expected
if all_strings?(actual, expected)
if any_multiline_strings?(actual, expected)
message << "\nDiff:" << differ.diff_as_string(coerce_to_string(actual), coerce_to_string(expected))
end
elsif no_procs?(actual, expected) && no_numbers?(actual, expected)
message << "\nDiff:" << differ.diff_as_object(actual, expected)
end
end
The all_strings?, any_multiline_strings?, no_procs?, and no_numbers? methods (defined in the same file) all invoke args.flatten on [actual, expected]. In this case, from what I can tell the problem is that actual is a TestResponse, which causes the flatten method itself to hang without raising a runtime error. I didn't have time to investigate this further, but the source for Array.flatten is here if anyone is interested.