1 files changed, 103 insertions, 0 deletions
diff --git a/activerecord/test/cases/attribute_test.rb b/activerecord/test/cases/attribute_test.rb
new file mode 100644
index 0000000000..57dd2e9a5e
--- /dev/null
+++ b/activerecord/test/cases/attribute_test.rb
@@ -0,0 +1,103 @@
+require 'cases/helper'
+require 'minitest/mock'
+
+module ActiveRecord
+  class AttributeTest < ActiveRecord::TestCase
+    setup do
+      @type = MiniTest::Mock.new
+    end
+
+    teardown do
+      assert @type.verify
+    end
+
+    test "from_database + read type casts from database" do
+      @type.expect(:type_cast_from_database, 'type cast from database', ['a value'])
+      attribute = Attribute.from_database('a value', @type)
+
+      type_cast_value = attribute.value
+
+      assert_equal 'type cast from database', type_cast_value
+    end
+
+    test "from_user + read type casts from user" do
+      @type.expect(:type_cast_from_user, 'type cast from user', ['a value'])
+      attribute = Attribute.from_user('a value', @type)
+
+      type_cast_value = attribute.value
+
+      assert_equal 'type cast from user', type_cast_value
+    end
+
+    test "reading memoizes the value" do
+      @type.expect(:type_cast_from_database, 'from the database', ['whatever'])
+      attribute = Attribute.from_database('whatever', @type)
+
+      type_cast_value = attribute.value
+      second_read = attribute.value
+
+      assert_equal 'from the database', type_cast_value
+      assert_same type_cast_value, second_read
+    end
+
+    test "reading memoizes falsy values" do
+      @type.expect(:type_cast_from_database, false, ['whatever'])
+      attribute = Attribute.from_database('whatever', @type)
+
+      attribute.value
+      attribute.value
+    end
+
+    test "read_before_typecast returns the given value" do
+      attribute = Attribute.from_database('raw value', @type)
+
+      raw_value = attribute.value_before_type_cast
+
+      assert_equal 'raw value', raw_value
+    end
+
+    test "from_database + read_for_database type casts to and from database" do
+      @type.expect(:type_cast_from_database, 'read from database', ['whatever'])
+      @type.expect(:type_cast_for_database, 'ready for database', ['read from database'])
+      attribute = Attribute.from_database('whatever', @type)
+
+      type_cast_for_database = attribute.value_for_database
+
+      assert_equal 'ready for database', type_cast_for_database
+    end
+
+    test "from_user + read_for_database type casts from the user to the database" do
+      @type.expect(:type_cast_from_user, 'read from user', ['whatever'])
+      @type.expect(:type_cast_for_database, 'ready for database', ['read from user'])
+      attribute = Attribute.from_user('whatever', @type)
+
+      type_cast_for_database = attribute.value_for_database
+
+      assert_equal 'ready for database', type_cast_for_database
+    end
+
+    test "duping dups the value" do
+      @type.expect(:type_cast_from_database, 'type cast', ['a value'])
+      attribute = Attribute.from_database('a value', @type)
+
+      value_from_orig = attribute.value
+      value_from_clone = attribute.dup.value
+      value_from_orig << ' foo'
+
+      assert_equal 'type cast foo', value_from_orig
+      assert_equal 'type cast', value_from_clone
+    end
+
+    test "duping does not dup the value if it is not dupable" do
+      @type.expect(:type_cast_from_database, false, ['a value'])
+      attribute = Attribute.from_database('a value', @type)
+
+      assert_same attribute.value, attribute.dup.value
+    end
+
+    test "duping does not eagerly type cast if we have not yet type cast" do
+      attribute = Attribute.from_database('a value', @type)
+      attribute.dup
+    end
+  end
+end