Conditional validations breaks client side validation

entry.rb

class Entry < ActiveRecord::Base

  validates :first_name, :presence => true, :length => {:maximum => 50}, :if => :condition?
  
  def condition?
    return true
  end
  
end

new.html.haml

= simple_form_for @entry, :validate => true do |f|

   = f.input :first_name, :validate => true, :required => true

You have to do:

= f.input :first_name, :input_html => { :validate => true }, :required => true

This is outlined in the SimpleForm wiki page:

https://github.com/bcardarella/client_side_validations/wiki/SimpleForm