chore: fix test syntax (#33)

Rakefile

@@ -2,6 +2,7 @@ require 'bundler/gem_tasks'
 require 'rake/testtask'
 
 Rake::TestTask.new do |t|
+  t.libs << 'test'
   t.test_files = FileList['test/*_test.rb']
 end
 

test/integration_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class IntegrationTest < BaseTestCase
   def test_should_be_registered

test/machine_by_default_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineByDefaultTest < BaseTestCase
   def setup

test/machine_errors_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineErrorsTest < BaseTestCase
   def setup

test/machine_multiple_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineMultipleTest < BaseTestCase
   def setup

test/machine_with_callbacks_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithCallbacksTest < BaseTestCase
   def setup

test/machine_with_dirty_attribute_and_custom_attributes_during_loopback_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithDirtyAttributeAndCustomAttributesDuringLoopbackTest < BaseTestCase
   def setup

test/machine_with_dirty_attribute_and_state_events_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithDirtyAttributeAndStateEventsTest < BaseTestCase
   def setup

test/machine_with_dirty_attributes_and_custom_attribute_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithDirtyAttributesAndCustomAttributeTest < BaseTestCase
   def setup

test/machine_with_dirty_attributes_during_loopback_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithDirtyAttributesDuringLoopbackTest < BaseTestCase
   def setup

test/machine_with_dirty_attributes_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithDirtyAttributesTest < BaseTestCase
   def setup

test/machine_with_dynamic_initial_state_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithDynamicInitialStateTest < BaseTestCase
   def setup

test/machine_with_events_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithEventsTest < BaseTestCase
   def setup

test/machine_with_failed_after_callbacks_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithFailedAfterCallbacksTest < BaseTestCase
   def setup

test/machine_with_failed_before_callbacks_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithFailedBeforeCallbacksTest < BaseTestCase
   def setup

test/machine_with_initialized_aliased_attribute_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithInitializedAliasedAttributeTest < BaseTestCase
   def test_should_match_original_attribute_value_with_attribute_methods

test/machine_with_initialized_state_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithInitializedStateTest < BaseTestCase
   def setup

test/machine_with_internationalization_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 require 'i18n'
 
 class MachineWithInternationalizationTest < BaseTestCase

test/machine_with_model_state_attribute_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithModelStateAttributeTest < BaseTestCase
   def setup

test/machine_with_non_model_state_attribute_undefined_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithNonModelStateAttributeUndefinedTest < BaseTestCase
   def setup

test/machine_with_state_driven_validations_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithStateDrivenValidationsTest < BaseTestCase
   def setup

test/machine_with_states_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithStatesTest < BaseTestCase
   def setup

test/machine_with_static_initial_state_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithStaticInitialStateTest < BaseTestCase
   def setup

test/machine_with_validations_and_custom_attribute_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithValidationsAndCustomAttributeTest < BaseTestCase
   def setup

test/machine_with_validations_test.rb

@@ -1,4 +1,4 @@
-require_relative 'test_helper'
+require 'test_helper'
 
 class MachineWithValidationsTest < BaseTestCase
   def setup