add test for transparent scopes

lib/state_machines/integrations/active_record.rb

@@ -565,7 +565,13 @@ def locale_path
 
         # Defines a new named scope with the given name
         def create_scope(name, scope)
-          lambda { |model, values| model.where(scope.call(values)) if values.present? }
+          ->(model, values) { values.present? ? model.where(scope.call(values)) : model }
+        end
+
+        # Generates the results for the given scope based on one or more states to filter by
+        def run_scope(scope, machine, klass, states)
+          values = states.compact.flatten.map { |state| machine.states.fetch(state).value }
+          scope.call(klass, values)
         end
 
         # ActiveModel's use of method_missing / respond_to for attribute methods

test/machine_with_scopes_test.rb

@@ -19,6 +19,13 @@ def test_should_only_include_records_with_state_in_singular_with_scope
     assert_equal [parked], @model.with_state(:parked).all
   end
 
+  def test_should_allow_transparent_with_state_in_singular_with_scope
+    @model.create :state => 'parked'
+    @model.create :state => 'idling'
+
+    assert_equal @model.all, @model.with_state(nil).all
+  end
+
   def test_should_create_plural_with_scope
     assert @model.respond_to?(:with_states)
   end
@@ -30,6 +37,13 @@ def test_should_only_include_records_with_states_in_plural_with_scope
     assert_equal [parked, idling], @model.with_states(:parked, :idling).all
   end
 
+  def test_should_allow_transparent_with_states_in_plural_with_scope
+    @model.create :state => 'parked'
+    @model.create :state => 'idling'
+
+    assert_equal @model.all, @model.with_states(nil).all
+  end
+
   def test_should_allow_lookup_by_string_name
     parked = @model.create :state => 'parked'
     idling = @model.create :state => 'idling'
@@ -43,28 +57,49 @@ def test_should_create_singular_without_scope
 
   def test_should_only_include_records_without_state_in_singular_without_scope
     parked = @model.create :state => 'parked'
-    idling = @model.create :state => 'idling'
+    @model.create :state => 'idling'
 
     assert_equal [parked], @model.without_state(:idling).all
   end
 
+  def test_allow_transparent_without_state_in_singular_without_scope
+    @model.create :state => 'parked'
+    @model.create :state => 'idling'
+
+    assert_equal @model.all, @model.without_state(nil).all
+  end
+
   def test_should_create_plural_without_scope
     assert @model.respond_to?(:without_states)
   end
 
   def test_should_only_include_records_without_states_in_plural_without_scope
     parked = @model.create :state => 'parked'
     idling = @model.create :state => 'idling'
-    first_gear = @model.create :state => 'first_gear'
+    @model.create :state => 'first_gear'
 
     assert_equal [parked, idling], @model.without_states(:first_gear).all
   end
 
+  def test_allow_transparent_without_states_in_plural_without_scope
+    @model.create :state => 'parked'
+    @model.create :state => 'idling'
+    @model.create :state => 'first_gear'
+
+    assert_equal @model.all, @model.without_states(nil).all
+  end
+
   def test_should_allow_chaining_scopes
-    parked = @model.create :state => 'parked'
+    @model.create :state => 'parked'
     idling = @model.create :state => 'idling'
 
     assert_equal [idling], @model.without_state(:parked).with_state(:idling).all
   end
-end
 
+  def test_should_allow_chaining_transparent_scopes
+    @model.create :state => 'parked'
+    idling = @model.create :state => 'idling'
+
+    assert_equal [idling], @model.with_state(nil).with_state(:idling).all
+  end
+end