How to test a Ruby Roda app using RSpec--passing an argument to app.new with initialize

[Nick A]

Hello, I posted this on StackOverflow but think it might be more appropriate here.

This question probably has a simple answer but I can't find any examples for what I am trying to do--Use Roda with RSpec3 so it is difficult to troubleshoot.

I am using Marston and Dees 'Effective Testing w/ RSpec3' book which uses Sinatra instead of Roda. I am having difficulty passing an object to API.new. From the book, this is what works with Sinatra but fails with 'wrong number of arguments' error when I substitute Roda.

Depending on whether I pass arguments with super or no no arguments with super(), the error switches to indicate that the failure occurs either at the initialize method or in the call to Rack::Test::Methods post in the spec.

I see that in Rack::Test in github repo README I may have to use Rack::Builder.parse_file("config.ru") but that didn't help.

Thanks for any thoughts, Nick

Here are the two errors that rspec shows.

When using super no brackets...

Failures:

1. MbrTrak::API POST /users when the user is successfully recorded returns the user id Failure/Error: post '/users', JSON.generate(user)

   ArgumentError: wrong number of arguments (given 1, expected 0)

   ./spec/unit/app/api_spec.rb:21:in `block (4 levels) in module:MbrTrak'

And when using super()...

1. MbrTrak::API POST /users when the user is successfully recorded returns the user id Failure/Error: super()

   ArgumentError: wrong number of arguments (given 0, expected 1)

   ./app/api.rb:8:in `initialize' ./spec/unit/app/api_spec.rb:10:in `new' ./spec/unit/app/api_spec.rb:10:in `app' ./spec/unit/app/api_spec.rb:21:in `block (4 levels) in module:MbrTrak'

Here is my api_spec.rb

1. require_relative '../../../app/api'
   require 'rack/test'
   
   module MbrTrak
     RecordResult = Struct.new(:success?, :expense_id, :error_message)
    
     RSpec.describe API do
       include Rack::Test::Methods
       def app
         API.new(directory: directory)
       end
       let(:directory) { instance_double('MbrTrak::Directory')}
      
       describe 'POST /users' do
         context 'when the user is successfully recorded' do
           it 'returns the user id' do
             user = { 'some' => 'user' }
             allow(directory).to receive(:record)
               .with(user)
               .and_return(RecordResult.new(true, 417, nil))
             post '/users', JSON.generate(user)
             parsed = JSON.parse(last_response.body)
             expect(parsed).to include('user_id' => 417)
           end
         end
       end
     end
   end

and my api.rb file

1. require 'roda'
   require 'json'
   
   module MbrTrak
     class API < Roda
       def initialize(directory: Directory.new)
         @directory = directory
         super()
       end
       plugin :render, escape: true
       plugin :json
       route do |r|
         r.on "users" do
           r.is Integer do |id|
             r.get do
               JSON.generate([])
             end
           end
           r.post do
             user = JSON.parse(request.body.read)
             result = @directory.record(user)
             JSON.generate('user_id' => result.user_id)
           end
         end
       end
     end
   end

and my config.ru

1. require "./app/api"
   
   run MbrTrak::API

and finally, Gemfile.lock

1. GEM
     remote: https://rubygems.org/
     specs:
       addressable (2.8.0)
         public_suffix (>= 2.0.2, < 5.0)
       bcrypt (3.1.16)
       coderay (1.1.3)
       diff-lcs (1.5.0)
       domain_name (0.5.20190701)
         unf (>= 0.0.5, < 1.0.0)
       dry-inflector (0.2.1)
       erubi (1.10.0)
       http (2.2.2)
         addressable (~> 2.3)
         http-cookie (~> 1.0)
         http-form_data (~> 1.0.1)
         http_parser.rb (~> 0.6.0)
       http-cookie (1.0.4)
         domain_name (~> 0.5)
       http-form_data (1.0.3)
       http_parser.rb (0.6.0)
       lucid_http (0.11.1)
         http (~> 2.1)
       nio4r (2.5.8)
       pg (1.3.2)
       public_suffix (4.0.6)
       puma (5.6.2)
         nio4r (~> 2.0)
       rack (2.2.3)
       rack-test (1.1.0)
         rack (>= 1.0, < 3)
       rack-unreloader (1.8.0)
       rake (13.0.6)
       roda (3.53.0)
         rack
       rspec (3.11.0)
         rspec-core (~> 3.11.0)
         rspec-expectations (~> 3.11.0)
         rspec-mocks (~> 3.11.0)
       rspec-core (3.11.0)
         rspec-support (~> 3.11.0)
       rspec-expectations (3.11.0)
         diff-lcs (>= 1.2.0, < 2.0)
         rspec-support (~> 3.11.0)
       rspec-its (1.2.0)
         rspec-core (>= 3.0.0)
         rspec-expectations (>= 3.0.0)
       rspec-mocks (3.11.0)
         diff-lcs (>= 1.2.0, < 2.0)
         rspec-support (~> 3.11.0)
       rspec-roda (0.2.2)
         dry-inflector
         rack-test (~> 1.0)
         roda
         rspec (~> 3.7)
         rspec-its (~> 1.2.0)
       rspec-support (3.11.0)
       rspec_sequel_matchers (0.5.0)
         sequel (>= 3.8.0)
       sequel (5.53.0)
       tilt (2.0.10)
       unf (0.1.4)
         unf_ext
       unf_ext (0.0.8)
   
   PLATFORMS
     ruby
   
   DEPENDENCIES
     bcrypt
     coderay
     erubi
     lucid_http
     pg
     puma
     rack-test
     rack-unreloader
     rake
     roda
     rspec
     rspec-roda
     rspec_sequel_matchers
     sequel
     tilt
   
   BUNDLED WITH
      2.1.4

[Jeremy Evans]

On Thu, Mar 3, 2022 at 3:49 PM Nick A <mega...@gmail.com> wrote:

Hello, I posted this on StackOverflow but think it might be more appropriate here.

1. module MbrTrak
     class API < Roda
       def initialize(directory: Directory.new)
         @directory = directory
         super()
       end
   

Here is the specific problem.  You are overriding Roda#initialize in an incompatible way, and calling super with no argument, when it is supposed to accept a rack env hash.

The more general problem is your testing.  You should not attempt to manually instantiate Roda instances.  Instead, use the Rack API:  API.call(rack_env_hash).  You'll have to build the env hash manually, or use something like Rack::MockRequest (comes with Rack).  A Roda app is the Roda subclass (API in your case), not an instance of that subclass (an instance is created per request).

Thanks,

Jeremy