Ensure sub_sequence_id is valid on sequence AST.

Gemfile

@@ -22,6 +22,7 @@ gem 'active_model_serializers', '~> 0.8.3'
 gem 'ice_cube'
 gem 'rack-cors', require: 'rack/cors'
 gem 'mysql'
+gem 'database_cleaner'
 
 source 'https://rails-assets.org' do
   gem 'rails-assets-lodash'

Gemfile.lock

@@ -107,6 +107,7 @@ GEM
       adamantium (~> 0.2.0)
       equalizer (~> 0.0.9)
     concurrent-ruby (1.0.2)
+    database_cleaner (1.5.3)
     diff-lcs (1.2.5)
     docile (1.1.5)
     domain_name (0.5.20160826)
@@ -352,6 +353,7 @@ DEPENDENCIES
   capybara
   codeclimate-test-reporter
   coffee-rails
+  database_cleaner
   devise!
   factory_girl_rails
   faker

app/models/sequence.rb

@@ -28,7 +28,10 @@ class Sequence < ActiveRecord::Base
       .defineArg(:data_type,       [String])
       .defineArg(:milliseconds,    [Fixnum])
       .defineArg(:message,         [String])
-      .defineArg(:sub_sequence_id, [Fixnum])
+      .defineArg(:sub_sequence_id, [Fixnum]) do |node|
+        missing = !exists?(node.value)
+        node.invalidate!("Sequence ##{ node.value } does not exist.") if missing
+      end
       .defineArg(:lhs,             [String])
       .defineArg(:op,              [String])
       .defineArg(:rhs,             [Fixnum])

spec/controllers/api/sequences/sequences_create_spec.rb

@@ -5,17 +5,14 @@ describe Api::SequencesController do
   include Devise::Test::ControllerHelpers
 
   describe '#create' do
-    let(:nodes) {
-      f = File.read("./spec/lib/celery_script/ast_fixture3.json")
-      JSON.parse(f)["body"]
-    }
-
     let(:user) { FactoryGirl.create(:user) }
+    let(:nodes) { sequence_body_for(user) }
 
     it 'handles a well formed AST in the body attribute' do
       sign_in user
       input = { name: "Scare Birds",
                 body: nodes }
+      sequence_body_for(user)
       post :create,
            input.merge(format: :json)
       expect(response.status).to eq(200)

spec/features/helpers.rb

@@ -1,4 +1,23 @@
 module Helpers
+  AST_FIXTURE = File.read("./spec/lib/celery_script/ast_fixture3.json").freeze
+
+  # Create a VALID fake sequence.body for a particular user. Creates a fake
+  # subsequence in the DB when called.
+  def sequence_body_for(input)
+    body = JSON.parse(AST_FIXTURE)["body"]
+    case input
+    when User; id = FactoryGirl.create(:sequence, device: user.device).id
+    when Sequence; id = input.id
+    else; raise "?????"
+    end
+    body.map! do |node|
+      has_subseq = node.dig("args", "sub_sequence_id");
+      node["args"]["sub_sequence_id"] = id if has_subseq
+      node
+    end
+    body
+  end
+
   def sign_in_as(user)
     # For when you're actually testing the login UI components. Otherwise,
     # consider using the devise test helper `sign_in`

spec/lib/celery_script/checker_spec.rb

@@ -1,9 +1,15 @@
 require 'spec_helper'
 
 describe CeleryScript::Checker do
-  file = File.read("./spec/lib/celery_script/ast_fixture3.json")
 
-  let(:hash) { JSON.parse(file).deep_symbolize_keys }
+  let(:hash) do
+    {
+      kind: "sequence",
+      args: {},
+      comment: "Properly formatted, syntactically valid sequence.",
+      body: sequence_body_for(FactoryGirl.create(:sequence))
+    }.deep_symbolize_keys
+  end
 
   let(:tree) do
       CeleryScript::AstNode.new(hash)

spec/mutations/sequences/create_spec.rb

@@ -3,10 +3,7 @@ require 'spec_helper'
 describe Sequences::Create do
   let(:user) { FactoryGirl.create(:user) }
   let(:device) { user.device }
-  let(:body) {
-    f = File.read("./spec/lib/celery_script/ast_fixture3.json")
-    JSON.parse(f)["body"]
-  }
+  let(:body) { sequence_body_for(user) }
 
   name = Faker::Pokemon.name
   let(:sequence_params) do

spec/spec_helper.rb

@@ -38,6 +38,11 @@ SmarfDoc.config do |c|
   c.output_file   = 'api_docs.md'
 end
 
+require 'database_cleaner'
+DatabaseCleaner.strategy = :truncation
+# then, whenever you need to clean the DB
+DatabaseCleaner.clean
+
 RSpec.configure do |config|
 
   config.backtrace_exclusion_patterns = [/gems/]
@@ -49,7 +54,6 @@ RSpec.configure do |config|
   if ENV['docs']
     config.before(:each, type: :controller) do
       SmarfDoc.run!(request, response)
-      ActiveRecord::Base.subclasses.(&:destroy_all)
     end
   end