rails/rails — pull request #7826 by sikachu (2012-10-03 01:50:19+00:00)
Title: Make `.validators_on` accept `:kind` option

Making `ActiveModel::Validators#validators_on` to accept a `:kind` option which will filter out the validators on a particular attribute based on its kind.

```ruby
Person.validators_on(:name)
# => [#,
# #0..99}>]

Person.validators_on(:name, :presence)
# => [#]
```