Using mongoid (3.0.1):

I have run into problems with the validator. Specifically, it will accept floats and even non-numbers for integer fields and the validation passes.

class MyTest
  include Mongoid::Document
  include Mongoid::Timestamps

  field :filesize, :type => Integer

  validates_numericality_of :filesize, :greater_than_or_equal_to => 0, :only_integer => true
end

mt = MyTest.new
mt.filesize = 5.9
mt.valid? # true
mt.filesize == 5 #true

That shouldn't be valid, but it says it is and truncates it to 5.

There's also this issue:

mt = MyTest.new
mt.filesize = 'horse'
mt.valid? # true
mt.filesize == 0 #true

This seems directly related to issue MONGOID-2137, which was closed. However, this is a relevant issue for us as it breaks the ActiveRecord validation API.