Add dedicated build in rails environment loading

lib/mutant.rb

@@ -41,6 +41,7 @@ module Mutant
 end # Mutant
 
 require 'mutant/bootstrap'
+require 'mutant/bootstrap/rails'
 require 'mutant/version'
 require 'mutant/env'
 require 'mutant/util'

lib/mutant/bootstrap.rb

@@ -31,6 +31,9 @@ module Bootstrap
  #
  # rubocop:disable Metrics/MethodLength
  def self.apply(world, config)
+ # TOOD: Have this behind a conditional.
+ config = Rails.call(world, config)
+
  env = Env
  .empty(world, config)
  .tap(&method(:infect))

lib/mutant/bootstrap/rails.rb

@@ -0,0 +1,49 @@
+module Mutant
+ module Bootstrap
+ class Rails
+ include Procto.call, Concord.new(:world, :config)
+
+ def call
+ world.stdout.puts('Loading mutant config from rails environment')
+
+ # TODO add env to world.
+ #
+ # Make actual env configurable
+ ENV['RAILS_ENV'] = 'test'
+
+ world.kernel.require('./config/environment.rb')
+
+ ::Rails.application.eager_load!
+
+ # TODO: preload engines, these *love* to pack things
+ # in the main project
+ #
+ # TODO: allow custom preload hooks.
+
+ add_rails_matchers
+ end
+
+ private
+
+ def add_rails_matchers
+ # This logic sucks, instead rails should be come a match expression
+ # possibly allow match expressions like: `ActionController.subclasses`
+ return config if config.matcher.match_expressions.any?
+
+ config.with(
+ matcher: config.matcher.with(match_expressions: rails_expressions)
+ )
+ end
+
+ def rails_expressions
+ expressions = [
+ ApplicationController,
+ *ApplicationController.subclasses,
+ ApplicationRecord,
+ *ApplicationRecord.subclasses
+ ].map { |klass| config.expression_parser.apply(klass.name).from_right }
+ end
+
+ end # Rails
+ end # Bootstrap
+end # Mutant