A method to return the errors associated with attribute, which returns nil, if no errors are associated with the specified attribute, the error message if one error is associated with the specified attribute, or an array of error messages if more than one error is associated with the specified attribute.

Examples

my_person = Person.new(params[:person])
my_person.errors.on('login')
# => nil

my_person.errors.add('login', 'can not be empty') if my_person.login == ''
my_person.errors.on('login')
# => 'can not be empty'

my_person.errors.add('login', 'can not be longer than 10 characters') if my_person.login.length > 10
my_person.errors.on('login')
# => ['can not be empty', 'can not be longer than 10 characters']

Source Code

# File active_resource/validations.rb, line 87
def on(attribute)
  errors = @errors[attribute.to_s]
  return nil if errors.nil?
  errors.size == 1 ? errors.first : errors
end