Simpler method to find the subclass name

Also added tests

lib/acts_as_list/active_record/acts/list.rb

@@ -84,7 +84,7 @@ def acts_as_list_top
             end
 
             def acts_as_list_class
-              @acts_as_list_class ||= eval('::'+self.class.name.to_s)
+              self.class
             end
 
             def position_column

test/shared_list_sub.rb

@@ -118,5 +118,10 @@ def test_delete_middle
       assert_equal 1, ListMixin.where(id: 3).first.pos
       assert_equal 2, ListMixin.where(id: 4).first.pos
     end
+
+    def test_acts_as_list_class
+      assert_equal TheSubClass1, TheSubClass1.new.acts_as_list_class
+      assert_equal TheSubClass2, TheSubClass2.new.acts_as_list_class
+    end
   end
 end

test/test_list.rb

@@ -92,6 +92,19 @@ class NoAdditionMixin < Mixin
   acts_as_list column: "pos", add_new_at: nil, scope: :parent_id
 end
 
+class TheBaseClass < ActiveRecord::Base
+  self.abstract_class = true
+  acts_as_list column: "pos", scope: :parent
+end
+
+class TheSubClass1 < TheBaseClass
+  self.table_name = 'mixins'
+end
+
+class TheSubClass2 < TheBaseClass
+  self.table_name = 'mixins'
+end
+
 class ActsAsListTestCase < Minitest::Test
   # No default test required as this class is abstract.
   # Need for test/unit.