You cannot use Widget _elements if the base_element_tag is :checkbox

[svetlalev]

When you have a custom widget which has a base_element_tag :checkbox the multiple accessor is not working.
Example widget:

class Toggle < PageObject::Elements::CheckBox
  def self.accessor_methods(accessor, name)
    // some accessor methods
  end
end
PageObject.register_widget :toggle, Toggle, :checkbox

When you define a multiple accessor:

class MyPage
  include PageObject

  toggles :my_toggle, id: 'some_id'
end

When you call it in you test, you get the following error:

NoMethodError: undefined method `checkboxs' for #<Watir::Browser:0x2e3e1221eca4e1fc url="https://some_url" title="xxx">
Did you mean?  checkboxes
               checkbox
from (eval):1:in `find_watir_elements'

Issue is coming from this line of code: as the base_element_tag is :checkbox, the_call we pass to find_watir_elements is "checkboxs" which is incorrect - it should be "checkboxes".

Possible solution:
define_widget_multiple_accessor can be changed to something like:

def self.define_widget_multiple_accessor(base_element_tag, widget_class, widget_tag)
  send(:define_method, "#{widget_tag}s_for") do |identifier|
    call_keyword = base_element_tag == :checkbox ? 'checkboxe' : base_element_tag
    find_watir_elements("#{call_keyword}s(identifier)", widget_class, identifier, base_element_tag)
  end
end