Add spec for the railtie.

Author: beauby

spec/railtie_spec.rb

@@ -0,0 +1,11 @@
+require 'rails_helper'
+
+describe JSONAPI::Rails::Railtie do
+  it 'registers the JSON API MIME type' do
+    expect(Mime[:jsonapi]).to eq('application/vnd.api+json')
+  end
+
+  it 'registers the params parser for the JSON API MIME type' do
+    expect(::ActionDispatch::Request.parameter_parsers[:jsonapi]).not_to be_nil
+  end
+end