Rails 3 to Rails 4 upgrade undefined method to_input_field_tag

I'm in the process of upgrading a Rails 3 application to Rails 4 and I get the error message undefined method to_input_field_tag for class ActionView::Helpers::InstanceTag NameError when trying to start the Rails server.

Looking at API Dock http://ift.tt/1OJKxQO it shows this method as deprecated or moved.

Has this been moved or what is an equivalent replacement for this in Rails 4?