Move actionpack/lib/action_view* into actionview/lib

1 files changed, 0 insertions, 1880 deletions

diff --git a/actionpack/lib/action_view/helpers/form_helper.rb b/actionpack/lib/action_view/helpers/form_helper.rb
deleted file mode 100644
index f64c0ca30b..0000000000
--- a/actionpack/lib/action_view/helpers/form_helper.rb
+++ /dev/null
@@ -1,1880 +0,0 @@
-require 'cgi'
-require 'action_view/helpers/date_helper'
-require 'action_view/helpers/tag_helper'
-require 'action_view/helpers/form_tag_helper'
-require 'action_view/helpers/active_model_helper'
-require 'action_view/helpers/tags'
-require 'action_view/model_naming'
-require 'active_support/core_ext/class/attribute_accessors'
-require 'active_support/core_ext/hash/slice'
-require 'active_support/core_ext/string/output_safety'
-require 'active_support/core_ext/string/inflections'
-
-module ActionView
-  # = Action View Form Helpers
-  module Helpers
-    # Form helpers are designed to make working with resources much easier
-    # compared to using vanilla HTML.
-    #
-    # Typically, a form designed to create or update a resource reflects the
-    # identity of the resource in several ways: (i) the url that the form is
-    # sent to (the form element's +action+ attribute) should result in a request
-    # being routed to the appropriate controller action (with the appropriate <tt>:id</tt>
-    # parameter in the case of an existing resource), (ii) input fields should
-    # be named in such a way that in the controller their values appear in the
-    # appropriate places within the +params+ hash, and (iii) for an existing record,
-    # when the form is initially displayed, input fields corresponding to attributes
-    # of the resource should show the current values of those attributes.
-    #
-    # In Rails, this is usually achieved by creating the form using +form_for+ and
-    # a number of related helper methods. +form_for+ generates an appropriate <tt>form</tt>
-    # tag and yields a form builder object that knows the model the form is about.
-    # Input fields are created by calling methods defined on the form builder, which
-    # means they are able to generate the appropriate names and default values
-    # corresponding to the model attributes, as well as convenient IDs, etc.
-    # Conventions in the generated field names allow controllers to receive form data
-    # nicely structured in +params+ with no effort on your side.
-    #
-    # For example, to create a new person you typically set up a new instance of
-    # +Person+ in the <tt>PeopleController#new</tt> action, <tt>@person</tt>, and
-    # in the view template pass that object to +form_for+:
-    #
-    #   <%= form_for @person do |f| %>
-    #     <%= f.label :first_name %>:
-    #     <%= f.text_field :first_name %><br />
-    #
-    #     <%= f.label :last_name %>:
-    #     <%= f.text_field :last_name %><br />
-    #
-    #     <%= f.submit %>
-    #   <% end %>
-    #
-    # The HTML generated for this would be (modulus formatting):
-    #
-    #   <form action="/people" class="new_person" id="new_person" method="post">
-    #     <div style="margin:0;padding:0;display:inline">
-    #       <input name="authenticity_token" type="hidden" value="NrOp5bsjoLRuK8IW5+dQEYjKGUJDe7TQoZVvq95Wteg=" />
-    #     </div>
-    #     <label for="person_first_name">First name</label>:
-    #     <input id="person_first_name" name="person[first_name]" type="text" /><br />
-    #
-    #     <label for="person_last_name">Last name</label>:
-    #     <input id="person_last_name" name="person[last_name]" type="text" /><br />
-    #
-    #     <input name="commit" type="submit" value="Create Person" />
-    #   </form>
-    #
-    # As you see, the HTML reflects knowledge about the resource in several spots,
-    # like the path the form should be submitted to, or the names of the input fields.
-    #
-    # In particular, thanks to the conventions followed in the generated field names, the
-    # controller gets a nested hash <tt>params[:person]</tt> with the person attributes
-    # set in the form. That hash is ready to be passed to <tt>Person.create</tt>:
-    #
-    #   if @person = Person.create(params[:person])
-    #     # success
-    #   else
-    #     # error handling
-    #   end
-    #
-    # Interestingly, the exact same view code in the previous example can be used to edit
-    # a person. If <tt>@person</tt> is an existing record with name "John Smith" and ID 256,
-    # the code above as is would yield instead:
-    #
-    #   <form action="/people/256" class="edit_person" id="edit_person_256" method="post">
-    #     <div style="margin:0;padding:0;display:inline">
-    #       <input name="_method" type="hidden" value="patch" />
-    #       <input name="authenticity_token" type="hidden" value="NrOp5bsjoLRuK8IW5+dQEYjKGUJDe7TQoZVvq95Wteg=" />
-    #     </div>
-    #     <label for="person_first_name">First name</label>:
-    #     <input id="person_first_name" name="person[first_name]" type="text" value="John" /><br />
-    #
-    #     <label for="person_last_name">Last name</label>:
-    #     <input id="person_last_name" name="person[last_name]" type="text" value="Smith" /><br />
-    #
-    #     <input name="commit" type="submit" value="Update Person" />
-    #   </form>
-    #
-    # Note that the endpoint, default values, and submit button label are tailored for <tt>@person</tt>.
-    # That works that way because the involved helpers know whether the resource is a new record or not,
-    # and generate HTML accordingly.
-    #
-    # The controller would receive the form data again in <tt>params[:person]</tt>, ready to be
-    # passed to <tt>Person#update</tt>:
-    #
-    #   if @person.update(params[:person])
-    #     # success
-    #   else
-    #     # error handling
-    #   end
-    #
-    # That's how you typically work with resources.
-    module FormHelper
-      extend ActiveSupport::Concern
-
-      include FormTagHelper
-      include UrlHelper
-      include ModelNaming
-
-      # Creates a form that allows the user to create or update the attributes
-      # of a specific model object.
-      #
-      # The method can be used in several slightly different ways, depending on
-      # how much you wish to rely on Rails to infer automatically from the model
-      # how the form should be constructed. For a generic model object, a form
-      # can be created by passing +form_for+ a string or symbol representing
-      # the object we are concerned with:
-      #
-      #   <%= form_for :person do |f| %>
-      #     First name: <%= f.text_field :first_name %><br />
-      #     Last name : <%= f.text_field :last_name %><br />
-      #     Biography : <%= f.text_area :biography %><br />
-      #     Admin?    : <%= f.check_box :admin %><br />
-      #     <%= f.submit %>
-      #   <% end %>
-      #
-      # The variable +f+ yielded to the block is a FormBuilder object that
-      # incorporates the knowledge about the model object represented by
-      # <tt>:person</tt> passed to +form_for+. Methods defined on the FormBuilder
-      # are used to generate fields bound to this model. Thus, for example,
-      #
-      #   <%= f.text_field :first_name %>
-      #
-      # will get expanded to
-      #
-      #   <%= text_field :person, :first_name %>
-      # which results in an html <tt><input></tt> tag whose +name+ attribute is
-      # <tt>person[first_name]</tt>. This means that when the form is submitted,
-      # the value entered by the user will be available in the controller as
-      # <tt>params[:person][:first_name]</tt>.
-      #
-      # For fields generated in this way using the FormBuilder,
-      # if <tt>:person</tt> also happens to be the name of an instance variable
-      # <tt>@person</tt>, the default value of the field shown when the form is
-      # initially displayed (e.g. in the situation where you are editing an
-      # existing record) will be the value of the corresponding attribute of
-      # <tt>@person</tt>.
-      #
-      # The rightmost argument to +form_for+ is an
-      # optional hash of options -
-      #
-      # * <tt>:url</tt> - The URL the form is to be submitted to. This may be
-      #   represented in the same way as values passed to +url_for+ or +link_to+.
-      #   So for example you may use a named route directly. When the model is
-      #   represented by a string or symbol, as in the example above, if the
-      #   <tt>:url</tt> option is not specified, by default the form will be
-      #   sent back to the current url (We will describe below an alternative
-      #   resource-oriented usage of +form_for+ in which the URL does not need
-      #   to be specified explicitly).
-      # * <tt>:namespace</tt> - A namespace for your form to ensure uniqueness of
-      #   id attributes on form elements. The namespace attribute will be prefixed
-      #   with underscore on the generated HTML id.
-      # * <tt>:html</tt> - Optional HTML attributes for the form tag.
-      #
-      # Also note that +form_for+ doesn't create an exclusive scope. It's still
-      # possible to use both the stand-alone FormHelper methods and methods
-      # from FormTagHelper. For example:
-      #
-      #   <%= form_for :person do |f| %>
-      #     First name: <%= f.text_field :first_name %>
-      #     Last name : <%= f.text_field :last_name %>
-      #     Biography : <%= text_area :person, :biography %>
-      #     Admin?    : <%= check_box_tag "person[admin]", "1", @person.company.admin? %>
-      #     <%= f.submit %>
-      #   <% end %>
-      #
-      # This also works for the methods in FormOptionHelper and DateHelper that
-      # are designed to work with an object as base, like
-      # FormOptionHelper#collection_select and DateHelper#datetime_select.
-      #
-      # === #form_for with a model object
-      #
-      # In the examples above, the object to be created or edited was
-      # represented by a symbol passed to +form_for+, and we noted that
-      # a string can also be used equivalently. It is also possible, however,
-      # to pass a model object itself to +form_for+. For example, if <tt>@post</tt>
-      # is an existing record you wish to edit, you can create the form using
-      #
-      #   <%= form_for @post do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # This behaves in almost the same way as outlined previously, with a
-      # couple of small exceptions. First, the prefix used to name the input
-      # elements within the form (hence the key that denotes them in the +params+
-      # hash) is actually derived from the object's _class_, e.g. <tt>params[:post]</tt>
-      # if the object's class is +Post+. However, this can be overwritten using
-      # the <tt>:as</tt> option, e.g. -
-      #
-      #   <%= form_for(@person, as: :client) do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # would result in <tt>params[:client]</tt>.
-      #
-      # Secondly, the field values shown when the form is initially displayed
-      # are taken from the attributes of the object passed to +form_for+,
-      # regardless of whether the object is an instance
-      # variable. So, for example, if we had a _local_ variable +post+
-      # representing an existing record,
-      #
-      #   <%= form_for post do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # would produce a form with fields whose initial state reflect the current
-      # values of the attributes of +post+.
-      #
-      # === Resource-oriented style
-      #
-      # In the examples just shown, although not indicated explicitly, we still
-      # need to use the <tt>:url</tt> option in order to specify where the
-      # form is going to be sent. However, further simplification is possible
-      # if the record passed to +form_for+ is a _resource_, i.e. it corresponds
-      # to a set of RESTful routes, e.g. defined using the +resources+ method
-      # in <tt>config/routes.rb</tt>. In this case Rails will simply infer the
-      # appropriate URL from the record itself. For example,
-      #
-      #   <%= form_for @post do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # is then equivalent to something like:
-      #
-      #   <%= form_for @post, as: :post, url: post_path(@post), method: :patch, html: { class: "edit_post", id: "edit_post_45" } do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # And for a new record
-      #
-      #   <%= form_for(Post.new) do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # is equivalent to something like:
-      #
-      #   <%= form_for @post, as: :post, url: posts_path, html: { class: "new_post", id: "new_post" } do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # However you can still overwrite individual conventions, such as:
-      #
-      #   <%= form_for(@post, url: super_posts_path) do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # You can also set the answer format, like this:
-      #
-      #   <%= form_for(@post, format: :json) do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # For namespaced routes, like +admin_post_url+:
-      #
-      #   <%= form_for([:admin, @post]) do |f| %>
-      #    ...
-      #   <% end %>
-      #
-      # If your resource has associations defined, for example, you want to add comments
-      # to the document given that the routes are set correctly:
-      #
-      #   <%= form_for([@document, @comment]) do |f| %>
-      #    ...
-      #   <% end %>
-      #
-      # Where <tt>@document = Document.find(params[:id])</tt> and
-      # <tt>@comment = Comment.new</tt>.
-      #
-      # === Setting the method
-      #
-      # You can force the form to use the full array of HTTP verbs by setting
-      #
-      #    method: (:get|:post|:patch|:put|:delete)
-      #
-      # in the options hash. If the verb is not GET or POST, which are natively
-      # supported by HTML forms, the form will be set to POST and a hidden input
-      # called _method will carry the intended verb for the server to interpret.
-      #
-      # === Unobtrusive JavaScript
-      #
-      # Specifying:
-      #
-      #    remote: true
-      #
-      # in the options hash creates a form that will allow the unobtrusive JavaScript drivers to modify its
-      # behavior. The expected default behavior is an XMLHttpRequest in the background instead of the regular
-      # POST arrangement, but ultimately the behavior is the choice of the JavaScript driver implementor.
-      # Even though it's using JavaScript to serialize the form elements, the form submission will work just like
-      # a regular submission as viewed by the receiving side (all elements available in <tt>params</tt>).
-      #
-      # Example:
-      #
-      #   <%= form_for(@post, remote: true) do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # The HTML generated for this would be:
-      #
-      #   <form action='http://www.example.com' method='post' data-remote='true'>
-      #     <div style='margin:0;padding:0;display:inline'>
-      #       <input name='_method' type='hidden' value='patch' />
-      #     </div>
-      #     ...
-      #   </form>
-      #
-      # === Setting HTML options
-      #
-      # You can set data attributes directly by passing in a data hash, but all other HTML options must be wrapped in
-      # the HTML key. Example:
-      #
-      #   <%= form_for(@post, data: { behavior: "autosave" }, html: { name: "go" }) do |f| %>
-      #     ...
-      #   <% end %>
-      #
-      # The HTML generated for this would be:
-      #
-      #   <form action='http://www.example.com' method='post' data-behavior='autosave' name='go'>
-      #     <div style='margin:0;padding:0;display:inline'>
-      #       <input name='_method' type='hidden' value='patch' />
-      #     </div>
-      #     ...
-      #   </form>
-      #
-      # === Removing hidden model id's
-      #
-      # The form_for method automatically includes the model id as a hidden field in the form.
-      # This is used to maintain the correlation between the form data and its associated model.
-      # Some ORM systems do not use IDs on nested models so in this case you want to be able
-      # to disable the hidden id.
-      #
-      # In the following example the Post model has many Comments stored within it in a NoSQL database,
-      # thus there is no primary key for comments.
-      #
-      # Example:
-      #
-      #   <%= form_for(@post) do |f| %>
-      #     <%= f.fields_for(:comments, include_id: false) do |cf| %>
-      #       ...
-      #     <% end %>
-      #   <% end %>
-      #
-      # === Customized form builders
-      #
-      # You can also build forms using a customized FormBuilder class. Subclass
-      # FormBuilder and override or define some more helpers, then use your
-      # custom builder. For example, let's say you made a helper to
-      # automatically add labels to form inputs.
-      #
-      #   <%= form_for @person, url: { action: "create" }, builder: LabellingFormBuilder do |f| %>
-      #     <%= f.text_field :first_name %>
-      #     <%= f.text_field :last_name %>
-      #     <%= f.text_area :biography %>
-      #     <%= f.check_box :admin %>
-      #     <%= f.submit %>
-      #   <% end %>
-      #
-      # In this case, if you use this:
-      #
-      #   <%= render f %>
-      #
-      # The rendered template is <tt>people/_labelling_form</tt> and the local
-      # variable referencing the form builder is called
-      # <tt>labelling_form</tt>.
-      #
-      # The custom FormBuilder class is automatically merged with the options
-      # of a nested fields_for call, unless it's explicitly set.
-      #
-      # In many cases you will want to wrap the above in another helper, so you
-      # could do something like the following:
-      #
-      #   def labelled_form_for(record_or_name_or_array, *args, &block)
-      #     options = args.extract_options!
-      #     form_for(record_or_name_or_array, *(args << options.merge(builder: LabellingFormBuilder)), &block)
-      #   end
-      #
-      # If you don't need to attach a form to a model instance, then check out
-      # FormTagHelper#form_tag.
-      #
-      # === Form to external resources
-      #
-      # When you build forms to external resources sometimes you need to set an authenticity token or just render a form
-      # without it, for example when you submit data to a payment gateway number and types of fields could be limited.
-      #
-      # To set an authenticity token you need to pass an <tt>:authenticity_token</tt> parameter
-      #
-      #   <%= form_for @invoice, url: external_url, authenticity_token: 'external_token' do |f|
-      #     ...
-      #   <% end %>
-      #
-      # If you don't want to an authenticity token field be rendered at all just pass <tt>false</tt>:
-      #
-      #   <%= form_for @invoice, url: external_url, authenticity_token: false do |f|
-      #     ...
-      #   <% end %>
-      def form_for(record, options = {}, &block)
-        raise ArgumentError, "Missing block" unless block_given?
-        html_options = options[:html] ||= {}
-
-        case record
-        when String, Symbol
-          object_name = record
-          object      = nil
-        else
-          object      = record.is_a?(Array) ? record.last : record
-          raise ArgumentError, "First argument in form cannot contain nil or be empty" unless object
-          object_name = options[:as] || model_name_from_record_or_class(object).param_key
-          apply_form_for_options!(record, object, options)
-        end
-
-        html_options[:data]   = options.delete(:data)   if options.has_key?(:data)
-        html_options[:remote] = options.delete(:remote) if options.has_key?(:remote)
-        html_options[:method] = options.delete(:method) if options.has_key?(:method)
-        html_options[:authenticity_token] = options.delete(:authenticity_token)
-
-        builder = instantiate_builder(object_name, object, options)
-        output  = capture(builder, &block)
-        html_options[:multipart] ||= builder.multipart?
-
-        form_tag(options[:url] || {}, html_options) { output }
-      end
-
-      def apply_form_for_options!(record, object, options) #:nodoc:
-        object = convert_to_model(object)
-
-        as = options[:as]
-        action, method = object.respond_to?(:persisted?) && object.persisted? ? [:edit, :patch] : [:new, :post]
-        options[:html].reverse_merge!(
-          class:  as ? "#{action}_#{as}" : dom_class(object, action),
-          id:     as ? "#{action}_#{as}" : [options[:namespace], dom_id(object, action)].compact.join("_").presence,
-          method: method
-        )
-
-        options[:url] ||= polymorphic_path(record, format: options.delete(:format))
-      end
-      private :apply_form_for_options!
-
-      # Creates a scope around a specific model object like form_for, but
-      # doesn't create the form tags themselves. This makes fields_for suitable
-      # for specifying additional model objects in the same form.
-      #
-      # Although the usage and purpose of +field_for+ is similar to +form_for+'s,
-      # its method signature is slightly different. Like +form_for+, it yields
-      # a FormBuilder object associated with a particular model object to a block,
-      # and within the block allows methods to be called on the builder to
-      # generate fields associated with the model object. Fields may reflect
-      # a model object in two ways - how they are named (hence how submitted
-      # values appear within the +params+ hash in the controller) and what
-      # default values are shown when the form the fields appear in is first
-      # displayed. In order for both of these features to be specified independently,
-      # both an object name (represented by either a symbol or string) and the
-      # object itself can be passed to the method separately -
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     First name: <%= person_form.text_field :first_name %>
-      #     Last name : <%= person_form.text_field :last_name %>
-      #
-      #     <%= fields_for :permission, @person.permission do |permission_fields| %>
-      #       Admin?  : <%= permission_fields.check_box :admin %>
-      #     <% end %>
-      #
-      #     <%= f.submit %>
-      #   <% end %>
-      #
-      # In this case, the checkbox field will be represented by an HTML +input+
-      # tag with the +name+ attribute <tt>permission[admin]</tt>, and the submitted
-      # value will appear in the controller as <tt>params[:permission][:admin]</tt>.
-      # If <tt>@person.permission</tt> is an existing record with an attribute
-      # +admin+, the initial state of the checkbox when first displayed will
-      # reflect the value of <tt>@person.permission.admin</tt>.
-      #
-      # Often this can be simplified by passing just the name of the model
-      # object to +fields_for+ -
-      #
-      #   <%= fields_for :permission do |permission_fields| %>
-      #     Admin?: <%= permission_fields.check_box :admin %>
-      #   <% end %>
-      #
-      # ...in which case, if <tt>:permission</tt> also happens to be the name of an
-      # instance variable <tt>@permission</tt>, the initial state of the input
-      # field will reflect the value of that variable's attribute <tt>@permission.admin</tt>.
-      #
-      # Alternatively, you can pass just the model object itself (if the first
-      # argument isn't a string or symbol +fields_for+ will realize that the
-      # name has been omitted) -
-      #
-      #   <%= fields_for @person.permission do |permission_fields| %>
-      #     Admin?: <%= permission_fields.check_box :admin %>
-      #   <% end %>
-      #
-      # and +fields_for+ will derive the required name of the field from the
-      # _class_ of the model object, e.g. if <tt>@person.permission</tt>, is
-      # of class +Permission+, the field will still be named <tt>permission[admin]</tt>.
-      #
-      # Note: This also works for the methods in FormOptionHelper and
-      # DateHelper that are designed to work with an object as base, like
-      # FormOptionHelper#collection_select and DateHelper#datetime_select.
-      #
-      # === Nested Attributes Examples
-      #
-      # When the object belonging to the current scope has a nested attribute
-      # writer for a certain attribute, fields_for will yield a new scope
-      # for that attribute. This allows you to create forms that set or change
-      # the attributes of a parent object and its associations in one go.
-      #
-      # Nested attribute writers are normal setter methods named after an
-      # association. The most common way of defining these writers is either
-      # with +accepts_nested_attributes_for+ in a model definition or by
-      # defining a method with the proper name. For example: the attribute
-      # writer for the association <tt>:address</tt> is called
-      # <tt>address_attributes=</tt>.
-      #
-      # Whether a one-to-one or one-to-many style form builder will be yielded
-      # depends on whether the normal reader method returns a _single_ object
-      # or an _array_ of objects.
-      #
-      # ==== One-to-one
-      #
-      # Consider a Person class which returns a _single_ Address from the
-      # <tt>address</tt> reader method and responds to the
-      # <tt>address_attributes=</tt> writer method:
-      #
-      #   class Person
-      #     def address
-      #       @address
-      #     end
-      #
-      #     def address_attributes=(attributes)
-      #       # Process the attributes hash
-      #     end
-      #   end
-      #
-      # This model can now be used with a nested fields_for, like so:
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :address do |address_fields| %>
-      #       Street  : <%= address_fields.text_field :street %>
-      #       Zip code: <%= address_fields.text_field :zip_code %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # When address is already an association on a Person you can use
-      # +accepts_nested_attributes_for+ to define the writer method for you:
-      #
-      #   class Person < ActiveRecord::Base
-      #     has_one :address
-      #     accepts_nested_attributes_for :address
-      #   end
-      #
-      # If you want to destroy the associated model through the form, you have
-      # to enable it first using the <tt>:allow_destroy</tt> option for
-      # +accepts_nested_attributes_for+:
-      #
-      #   class Person < ActiveRecord::Base
-      #     has_one :address
-      #     accepts_nested_attributes_for :address, allow_destroy: true
-      #   end
-      #
-      # Now, when you use a form element with the <tt>_destroy</tt> parameter,
-      # with a value that evaluates to +true+, you will destroy the associated
-      # model (eg. 1, '1', true, or 'true'):
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :address do |address_fields| %>
-      #       ...
-      #       Delete: <%= address_fields.check_box :_destroy %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # ==== One-to-many
-      #
-      # Consider a Person class which returns an _array_ of Project instances
-      # from the <tt>projects</tt> reader method and responds to the
-      # <tt>projects_attributes=</tt> writer method:
-      #
-      #   class Person
-      #     def projects
-      #       [@project1, @project2]
-      #     end
-      #
-      #     def projects_attributes=(attributes)
-      #       # Process the attributes hash
-      #     end
-      #   end
-      #
-      # Note that the <tt>projects_attributes=</tt> writer method is in fact
-      # required for fields_for to correctly identify <tt>:projects</tt> as a
-      # collection, and the correct indices to be set in the form markup.
-      #
-      # When projects is already an association on Person you can use
-      # +accepts_nested_attributes_for+ to define the writer method for you:
-      #
-      #   class Person < ActiveRecord::Base
-      #     has_many :projects
-      #     accepts_nested_attributes_for :projects
-      #   end
-      #
-      # This model can now be used with a nested fields_for. The block given to
-      # the nested fields_for call will be repeated for each instance in the
-      # collection:
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :projects do |project_fields| %>
-      #       <% if project_fields.object.active? %>
-      #         Name: <%= project_fields.text_field :name %>
-      #       <% end %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # It's also possible to specify the instance to be used:
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <% @person.projects.each do |project| %>
-      #       <% if project.active? %>
-      #         <%= person_form.fields_for :projects, project do |project_fields| %>
-      #           Name: <%= project_fields.text_field :name %>
-      #         <% end %>
-      #       <% end %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # Or a collection to be used:
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :projects, @active_projects do |project_fields| %>
-      #       Name: <%= project_fields.text_field :name %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # If you want to destroy any of the associated models through the
-      # form, you have to enable it first using the <tt>:allow_destroy</tt>
-      # option for +accepts_nested_attributes_for+:
-      #
-      #   class Person < ActiveRecord::Base
-      #     has_many :projects
-      #     accepts_nested_attributes_for :projects, allow_destroy: true
-      #   end
-      #
-      # This will allow you to specify which models to destroy in the
-      # attributes hash by adding a form element for the <tt>_destroy</tt>
-      # parameter with a value that evaluates to +true+
-      # (eg. 1, '1', true, or 'true'):
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :projects do |project_fields| %>
-      #       Delete: <%= project_fields.check_box :_destroy %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # When a collection is used you might want to know the index of each
-      # object into the array. For this purpose, the <tt>index</tt> method
-      # is available in the FormBuilder object.
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :projects do |project_fields| %>
-      #       Project #<%= project_fields.index %>
-      #       ...
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # Note that fields_for will automatically generate a hidden field
-      # to store the ID of the record. There are circumstances where this
-      # hidden field is not needed and you can pass <tt>include_id: false</tt>
-      # to prevent fields_for from rendering it automatically.
-      def fields_for(record_name, record_object = nil, options = {}, &block)
-        builder = instantiate_builder(record_name, record_object, options)
-        capture(builder, &block)
-      end
-
-      # Returns a label tag tailored for labelling an input field for a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). The text of label will default to the attribute name unless a translation
-      # is found in the current I18n locale (through helpers.label.<modelname>.<attribute>) or you specify it explicitly.
-      # Additional options on the label tag can be passed as a hash with +options+. These options will be tagged
-      # onto the HTML as an HTML element attribute as in the example shown, except for the <tt>:value</tt> option, which is designed to
-      # target labels for radio_button tags (where the value is used in the ID of the input tag).
-      #
-      # ==== Examples
-      #   label(:post, :title)
-      #   # => <label for="post_title">Title</label>
-      #
-      # You can localize your labels based on model and attribute names.
-      # For example you can define the following in your locale (e.g. en.yml)
-      #
-      #   helpers:
-      #     label:
-      #       post:
-      #         body: "Write your entire text here"
-      #
-      # Which then will result in
-      #
-      #   label(:post, :body)
-      #   # => <label for="post_body">Write your entire text here</label>
-      #
-      # Localization can also be based purely on the translation of the attribute-name
-      # (if you are using ActiveRecord):
-      #
-      #   activerecord:
-      #     attributes:
-      #       post:
-      #         cost: "Total cost"
-      #
-      #   label(:post, :cost)
-      #   # => <label for="post_cost">Total cost</label>
-      #
-      #   label(:post, :title, "A short title")
-      #   # => <label for="post_title">A short title</label>
-      #
-      #   label(:post, :title, "A short title", class: "title_label")
-      #   # => <label for="post_title" class="title_label">A short title</label>
-      #
-      #   label(:post, :privacy, "Public Post", value: "public")
-      #   # => <label for="post_privacy_public">Public Post</label>
-      #
-      #   label(:post, :terms) do
-      #     'Accept <a href="/terms">Terms</a>.'.html_safe
-      #   end
-      def label(object_name, method, content_or_options = nil, options = nil, &block)
-        Tags::Label.new(object_name, method, self, content_or_options, options).render(&block)
-      end
-
-      # Returns an input tag of the "text" type tailored for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). Additional options on the input tag can be passed as a
-      # hash with +options+. These options will be tagged onto the HTML as an HTML element attribute as in the example
-      # shown.
-      #
-      # ==== Examples
-      #   text_field(:post, :title, size: 20)
-      #   # => <input type="text" id="post_title" name="post[title]" size="20" value="#{@post.title}" />
-      #
-      #   text_field(:post, :title, class: "create_input")
-      #   # => <input type="text" id="post_title" name="post[title]" value="#{@post.title}" class="create_input" />
-      #
-      #   text_field(:session, :user, onchange: "if ($('#session_user').val() === 'admin') { alert('Your login can not be admin!'); }")
-      #   # => <input type="text" id="session_user" name="session[user]" value="#{@session.user}" onchange="if ($('#session_user').val() === 'admin') { alert('Your login can not be admin!'); }"/>
-      #
-      #   text_field(:snippet, :code, size: 20, class: 'code_input')
-      #   # => <input type="text" id="snippet_code" name="snippet[code]" size="20" value="#{@snippet.code}" class="code_input" />
-      def text_field(object_name, method, options = {})
-        Tags::TextField.new(object_name, method, self, options).render
-      end
-
-      # Returns an input tag of the "password" type tailored for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). Additional options on the input tag can be passed as a
-      # hash with +options+. These options will be tagged onto the HTML as an HTML element attribute as in the example
-      # shown. For security reasons this field is blank by default; pass in a value via +options+ if this is not desired.
-      #
-      # ==== Examples
-      #   password_field(:login, :pass, size: 20)
-      #   # => <input type="password" id="login_pass" name="login[pass]" size="20" />
-      #
-      #   password_field(:account, :secret, class: "form_input", value: @account.secret)
-      #   # => <input type="password" id="account_secret" name="account[secret]" value="#{@account.secret}" class="form_input" />
-      #
-      #   password_field(:user, :password, onchange: "if ($('#user_password').val().length > 30) { alert('Your password needs to be shorter!'); }")
-      #   # => <input type="password" id="user_password" name="user[password]" onchange="if ($('#user_password').val().length > 30) { alert('Your password needs to be shorter!'); }"/>
-      #
-      #   password_field(:account, :pin, size: 20, class: 'form_input')
-      #   # => <input type="password" id="account_pin" name="account[pin]" size="20" class="form_input" />
-      def password_field(object_name, method, options = {})
-        Tags::PasswordField.new(object_name, method, self, options).render
-      end
-
-      # Returns a hidden input tag tailored for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). Additional options on the input tag can be passed as a
-      # hash with +options+. These options will be tagged onto the HTML as an HTML element attribute as in the example
-      # shown.
-      #
-      # ==== Examples
-      #   hidden_field(:signup, :pass_confirm)
-      #   # => <input type="hidden" id="signup_pass_confirm" name="signup[pass_confirm]" value="#{@signup.pass_confirm}" />
-      #
-      #   hidden_field(:post, :tag_list)
-      #   # => <input type="hidden" id="post_tag_list" name="post[tag_list]" value="#{@post.tag_list}" />
-      #
-      #   hidden_field(:user, :token)
-      #   # => <input type="hidden" id="user_token" name="user[token]" value="#{@user.token}" />
-      def hidden_field(object_name, method, options = {})
-        Tags::HiddenField.new(object_name, method, self, options).render
-      end
-
-      # Returns a file upload input tag tailored for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). Additional options on the input tag can be passed as a
-      # hash with +options+. These options will be tagged onto the HTML as an HTML element attribute as in the example
-      # shown.
-      #
-      # Using this method inside a +form_for+ block will set the enclosing form's encoding to <tt>multipart/form-data</tt>.
-      #
-      # ==== Options
-      # * Creates standard HTML attributes for the tag.
-      # * <tt>:disabled</tt> - If set to true, the user will not be able to use this input.
-      # * <tt>:multiple</tt> - If set to true, *in most updated browsers* the user will be allowed to select multiple files.
-      # * <tt>:accept</tt> - If set to one or multiple mime-types, the user will be suggested a filter when choosing a file. You still need to set up model validations.
-      #
-      # ==== Examples
-      #   file_field(:user, :avatar)
-      #   # => <input type="file" id="user_avatar" name="user[avatar]" />
-      #
-      #   file_field(:post, :image, :multiple => true)
-      #   # => <input type="file" id="post_image" name="post[image]" multiple="true" />
-      #
-      #   file_field(:post, :attached, accept: 'text/html')
-      #   # => <input accept="text/html" type="file" id="post_attached" name="post[attached]" />
-      #
-      #   file_field(:post, :image, accept: 'image/png,image/gif,image/jpeg')
-      #   # => <input type="file" id="post_image" name="post[image]" accept="image/png,image/gif,image/jpeg" />
-      #
-      #   file_field(:attachment, :file, class: 'file_input')
-      #   # => <input type="file" id="attachment_file" name="attachment[file]" class="file_input" />
-      def file_field(object_name, method, options = {})
-        Tags::FileField.new(object_name, method, self, options).render
-      end
-
-      # Returns a textarea opening and closing tag set tailored for accessing a specified attribute (identified by +method+)
-      # on an object assigned to the template (identified by +object+). Additional options on the input tag can be passed as a
-      # hash with +options+.
-      #
-      # ==== Examples
-      #   text_area(:post, :body, cols: 20, rows: 40)
-      #   # => <textarea cols="20" rows="40" id="post_body" name="post[body]">
-      #   #      #{@post.body}
-      #   #    </textarea>
-      #
-      #   text_area(:comment, :text, size: "20x30")
-      #   # => <textarea cols="20" rows="30" id="comment_text" name="comment[text]">
-      #   #      #{@comment.text}
-      #   #    </textarea>
-      #
-      #   text_area(:application, :notes, cols: 40, rows: 15, class: 'app_input')
-      #   # => <textarea cols="40" rows="15" id="application_notes" name="application[notes]" class="app_input">
-      #   #      #{@application.notes}
-      #   #    </textarea>
-      #
-      #   text_area(:entry, :body, size: "20x20", disabled: 'disabled')
-      #   # => <textarea cols="20" rows="20" id="entry_body" name="entry[body]" disabled="disabled">
-      #   #      #{@entry.body}
-      #   #    </textarea>
-      def text_area(object_name, method, options = {})
-        Tags::TextArea.new(object_name, method, self, options).render
-      end
-
-      # Returns a checkbox tag tailored for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). This object must be an instance object (@object) and not a local object.
-      # It's intended that +method+ returns an integer and if that integer is above zero, then the checkbox is checked.
-      # Additional options on the input tag can be passed as a hash with +options+. The +checked_value+ defaults to 1
-      # while the default +unchecked_value+ is set to 0 which is convenient for boolean values.
-      #
-      # ==== Gotcha
-      #
-      # The HTML specification says unchecked check boxes are not successful, and
-      # thus web browsers do not send them. Unfortunately this introduces a gotcha:
-      # if an +Invoice+ model has a +paid+ flag, and in the form that edits a paid
-      # invoice the user unchecks its check box, no +paid+ parameter is sent. So,
-      # any mass-assignment idiom like
-      #
-      #   @invoice.update(params[:invoice])
-      #
-      # wouldn't update the flag.
-      #
-      # To prevent this the helper generates an auxiliary hidden field before
-      # the very check box. The hidden field has the same name and its
-      # attributes mimic an unchecked check box.
-      #
-      # This way, the client either sends only the hidden field (representing
-      # the check box is unchecked), or both fields. Since the HTML specification
-      # says key/value pairs have to be sent in the same order they appear in the
-      # form, and parameters extraction gets the last occurrence of any repeated
-      # key in the query string, that works for ordinary forms.
-      #
-      # Unfortunately that workaround does not work when the check box goes
-      # within an array-like parameter, as in
-      #
-      #   <%= fields_for "project[invoice_attributes][]", invoice, index: nil do |form| %>
-      #     <%= form.check_box :paid %>
-      #     ...
-      #   <% end %>
-      #
-      # because parameter name repetition is precisely what Rails seeks to distinguish
-      # the elements of the array. For each item with a checked check box you
-      # get an extra ghost item with only that attribute, assigned to "0".
-      #
-      # In that case it is preferable to either use +check_box_tag+ or to use
-      # hashes instead of arrays.
-      #
-      #   # Let's say that @post.validated? is 1:
-      #   check_box("post", "validated")
-      #   # => <input name="post[validated]" type="hidden" value="0" />
-      #   #    <input checked="checked" type="checkbox" id="post_validated" name="post[validated]" value="1" />
-      #
-      #   # Let's say that @puppy.gooddog is "no":
-      #   check_box("puppy", "gooddog", {}, "yes", "no")
-      #   # => <input name="puppy[gooddog]" type="hidden" value="no" />
-      #   #    <input type="checkbox" id="puppy_gooddog" name="puppy[gooddog]" value="yes" />
-      #
-      #   check_box("eula", "accepted", { class: 'eula_check' }, "yes", "no")
-      #   # => <input name="eula[accepted]" type="hidden" value="no" />
-      #   #    <input type="checkbox" class="eula_check" id="eula_accepted" name="eula[accepted]" value="yes" />
-      def check_box(object_name, method, options = {}, checked_value = "1", unchecked_value = "0")
-        Tags::CheckBox.new(object_name, method, self, checked_value, unchecked_value, options).render
-      end
-
-      # Returns a radio button tag for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). If the current value of +method+ is +tag_value+ the
-      # radio button will be checked.
-      #
-      # To force the radio button to be checked pass <tt>checked: true</tt> in the
-      # +options+ hash. You may pass HTML options there as well.
-      #
-      #   # Let's say that @post.category returns "rails":
-      #   radio_button("post", "category", "rails")
-      #   radio_button("post", "category", "java")
-      #   # => <input type="radio" id="post_category_rails" name="post[category]" value="rails" checked="checked" />
-      #   #    <input type="radio" id="post_category_java" name="post[category]" value="java" />
-      #
-      #   radio_button("user", "receive_newsletter", "yes")
-      #   radio_button("user", "receive_newsletter", "no")
-      #   # => <input type="radio" id="user_receive_newsletter_yes" name="user[receive_newsletter]" value="yes" />
-      #   #    <input type="radio" id="user_receive_newsletter_no" name="user[receive_newsletter]" value="no" checked="checked" />
-      def radio_button(object_name, method, tag_value, options = {})
-        Tags::RadioButton.new(object_name, method, self, tag_value, options).render
-      end
-
-      # Returns a text_field of type "color".
-      #
-      #   color_field("car", "color")
-      #   # => <input id="car_color" name="car[color]" type="color" value="#000000" />
-      def color_field(object_name, method, options = {})
-        Tags::ColorField.new(object_name, method, self, options).render
-      end
-
-      # Returns an input of type "search" for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object_name+). Inputs of type "search" may be styled differently by
-      # some browsers.
-      #
-      #   search_field(:user, :name)
-      #   # => <input id="user_name" name="user[name]" type="search" />
-      #   search_field(:user, :name, autosave: false)
-      #   # => <input autosave="false" id="user_name" name="user[name]" type="search" />
-      #   search_field(:user, :name, results: 3)
-      #   # => <input id="user_name" name="user[name]" results="3" type="search" />
-      #   #  Assume request.host returns "www.example.com"
-      #   search_field(:user, :name, autosave: true)
-      #   # => <input autosave="com.example.www" id="user_name" name="user[name]" results="10" type="search" />
-      #   search_field(:user, :name, onsearch: true)
-      #   # => <input id="user_name" incremental="true" name="user[name]" onsearch="true" type="search" />
-      #   search_field(:user, :name, autosave: false, onsearch: true)
-      #   # => <input autosave="false" id="user_name" incremental="true" name="user[name]" onsearch="true" type="search" />
-      #   search_field(:user, :name, autosave: true, onsearch: true)
-      #   # => <input autosave="com.example.www" id="user_name" incremental="true" name="user[name]" onsearch="true" results="10" type="search" />
-      def search_field(object_name, method, options = {})
-        Tags::SearchField.new(object_name, method, self, options).render
-      end
-
-      # Returns a text_field of type "tel".
-      #
-      #   telephone_field("user", "phone")
-      #   # => <input id="user_phone" name="user[phone]" type="tel" />
-      #
-      def telephone_field(object_name, method, options = {})
-        Tags::TelField.new(object_name, method, self, options).render
-      end
-      # aliases telephone_field
-      alias phone_field telephone_field
-
-      # Returns a text_field of type "date".
-      #
-      #   date_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="date" />
-      #
-      # The default value is generated by trying to call "to_date"
-      # on the object's value, which makes it behave as expected for instances
-      # of DateTime and ActiveSupport::TimeWithZone. You can still override that
-      # by passing the "value" option explicitly, e.g.
-      #
-      #   @user.born_on = Date.new(1984, 1, 27)
-      #   date_field("user", "born_on", value: "1984-05-12")
-      #   # => <input id="user_born_on" name="user[born_on]" type="date" value="1984-05-12" />
-      #
-      def date_field(object_name, method, options = {})
-        Tags::DateField.new(object_name, method, self, options).render
-      end
-
-      # Returns a text_field of type "time".
-      #
-      # The default value is generated by trying to call +strftime+ with "%T.%L"
-      # on the objects's value. It is still possible to override that
-      # by passing the "value" option.
-      #
-      # === Options
-      # * Accepts same options as time_field_tag
-      #
-      # === Example
-      #   time_field("task", "started_at")
-      #   # => <input id="task_started_at" name="task[started_at]" type="time" />
-      #
-      def time_field(object_name, method, options = {})
-        Tags::TimeField.new(object_name, method, self, options).render
-      end
-
-      # Returns a text_field of type "datetime".
-      #
-      #   datetime_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="datetime" />
-      #
-      # The default value is generated by trying to call +strftime+ with "%Y-%m-%dT%T.%L%z"
-      # on the object's value, which makes it behave as expected for instances
-      # of DateTime and ActiveSupport::TimeWithZone.
-      #
-      #   @user.born_on = Date.new(1984, 1, 12)
-      #   datetime_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="datetime" value="1984-01-12T00:00:00.000+0000" />
-      #
-      def datetime_field(object_name, method, options = {})
-        Tags::DatetimeField.new(object_name, method, self, options).render
-      end
-
-      # Returns a text_field of type "datetime-local".
-      #
-      #   datetime_local_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="datetime-local" />
-      #
-      # The default value is generated by trying to call +strftime+ with "%Y-%m-%dT%T"
-      # on the object's value, which makes it behave as expected for instances
-      # of DateTime and ActiveSupport::TimeWithZone.
-      #
-      #   @user.born_on = Date.new(1984, 1, 12)
-      #   datetime_local_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="datetime-local" value="1984-01-12T00:00:00" />
-      #
-      def datetime_local_field(object_name, method, options = {})
-        Tags::DatetimeLocalField.new(object_name, method, self, options).render
-      end
-
-      # Returns a text_field of type "month".
-      #
-      #   month_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="month" />
-      #
-      # The default value is generated by trying to call +strftime+ with "%Y-%m"
-      # on the object's value, which makes it behave as expected for instances
-      # of DateTime and ActiveSupport::TimeWithZone.
-      #
-      #   @user.born_on = Date.new(1984, 1, 27)
-      #   month_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="date" value="1984-01" />
-      #
-      def month_field(object_name, method, options = {})
-        Tags::MonthField.new(object_name, method, self, options).render
-      end
-
-      # Returns a text_field of type "week".
-      #
-      #   week_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="week" />
-      #
-      # The default value is generated by trying to call +strftime+ with "%Y-W%W"
-      # on the object's value, which makes it behave as expected for instances
-      # of DateTime and ActiveSupport::TimeWithZone.
-      #
-      #   @user.born_on = Date.new(1984, 5, 12)
-      #   week_field("user", "born_on")
-      #   # => <input id="user_born_on" name="user[born_on]" type="date" value="1984-W19" />
-      #
-      def week_field(object_name, method, options = {})
-        Tags::WeekField.new(object_name, method, self, options).render
-      end
-
-      # Returns a text_field of type "url".
-      #
-      #   url_field("user", "homepage")
-      #   # => <input id="user_homepage" name="user[homepage]" type="url" />
-      #
-      def url_field(object_name, method, options = {})
-        Tags::UrlField.new(object_name, method, self, options).render
-      end
-
-      # Returns a text_field of type "email".
-      #
-      #   email_field("user", "address")
-      #   # => <input id="user_address" name="user[address]" type="email" />
-      #
-      def email_field(object_name, method, options = {})
-        Tags::EmailField.new(object_name, method, self, options).render
-      end
-
-      # Returns an input tag of type "number".
-      #
-      # ==== Options
-      # * Accepts same options as number_field_tag
-      def number_field(object_name, method, options = {})
-        Tags::NumberField.new(object_name, method, self, options).render
-      end
-
-      # Returns an input tag of type "range".
-      #
-      # ==== Options
-      # * Accepts same options as range_field_tag
-      def range_field(object_name, method, options = {})
-        Tags::RangeField.new(object_name, method, self, options).render
-      end
-
-      private
-
-        def instantiate_builder(record_name, record_object, options)
-          case record_name
-          when String, Symbol
-            object = record_object
-            object_name = record_name
-          else
-            object = record_name
-            object_name = model_name_from_record_or_class(object).param_key
-          end
-
-          builder = options[:builder] || default_form_builder
-          builder.new(object_name, object, self, options)
-        end
-
-        def default_form_builder
-          builder = ActionView::Base.default_form_builder
-          builder.respond_to?(:constantize) ? builder.constantize : builder
-        end
-    end
-
-    # A +FormBuilder+ object is associated with a particular model object and
-    # allows you to generate fields associated with the model object. The
-    # +FormBuilder+ object is yielded when using +form_for+ or +fields_for+.
-    # For example:
-    #
-    #   <%= form_for @person do |person_form| %>
-    #     Name: <%= person_form.text_field :name %>
-    #     Admin: <%= person_form.check_box :admin %>
-    #   <% end %>
-    #
-    # In the above block, the a +FormBuilder+ object is yielded as the
-    # +person_form+ variable. This allows you to generate the +text_field+
-    # and +check_box+ fields by specifying their eponymous methods, which
-    # modify the underlying template and associates the +@person+ model object
-    # with the form.
-    #
-    # The +FormBuilder+ object can be thought of as serving as a proxy for the
-    # methods in the +FormHelper+ module. This class, however, allows you to
-    # call methods with the model object you are building the form for.
-    #
-    # You can create your own custom FormBuilder templates by subclasses this
-    # class. For example:
-    #
-    #   class MyFormBuilder < ActionView::Helpers::FormBuilder
-    #     def div_radio_button(method, tag_value, options = {})
-    #       @template.content_tag(:div,
-    #         @template.radio_button(
-    #           @object_name, method, tag_value, objectify_options(options)
-    #         )
-    #       )
-    #     end
-    #
-    # The above code creates a new method +div_radio_button+ which wraps a div
-    # around the a new radio button. Note that when options are passed in, you
-    # must called +objectify_options+ in order for the model object to get
-    # correctly passed to the method. If +objectify_options+ is not called,
-    # then the newly created helper will not be linked back to the model.
-    #
-    # The +div_radio_button+ code from above can now be used as follows:
-    #
-    #   <%= form_for @person, :builder => MyFormBuilder do |f| %>
-    #     I am a child: <%= f.div_radio_button(:admin, "child") %>
-    #     I am an adult: <%= f.div_radio_button(:admin, "adult") %>
-    #   <% end -%>
-    #
-    # The standard set of helper methods for form building are located in the
-    # +field_helpers+ class attribute.
-    class FormBuilder
-      include ModelNaming
-
-      # The methods which wrap a form helper call.
-      class_attribute :field_helpers
-      self.field_helpers = [:fields_for, :label, :text_field, :password_field,
-                            :hidden_field, :file_field, :text_area, :check_box,
-                            :radio_button, :color_field, :search_field,
-                            :telephone_field, :phone_field, :date_field,
-                            :time_field, :datetime_field, :datetime_local_field,
-                            :month_field, :week_field, :url_field, :email_field,
-                            :number_field, :range_field]
-
-      attr_accessor :object_name, :object, :options
-
-      attr_reader :multipart, :index
-      alias :multipart? :multipart
-
-      def multipart=(multipart)
-        @multipart = multipart
-
-        if parent_builder = @options[:parent_builder]
-          parent_builder.multipart = multipart
-        end
-      end
-
-      def self._to_partial_path
-        @_to_partial_path ||= name.demodulize.underscore.sub!(/_builder$/, '')
-      end
-
-      def to_partial_path
-        self.class._to_partial_path
-      end
-
-      def to_model
-        self
-      end
-
-      def initialize(object_name, object, template, options, block=nil)
-        if block
-          ActiveSupport::Deprecation.warn "Giving a block to FormBuilder is deprecated and has no effect anymore."
-        end
-
-        @nested_child_index = {}
-        @object_name, @object, @template, @options = object_name, object, template, options
-        @default_options = @options ? @options.slice(:index, :namespace) : {}
-        if @object_name.to_s.match(/\[\]$/)
-          if object ||= @template.instance_variable_get("@#{Regexp.last_match.pre_match}") and object.respond_to?(:to_param)
-            @auto_index = object.to_param
-          else
-            raise ArgumentError, "object[] naming but object param and @object var don't exist or don't respond to to_param: #{object.inspect}"
-          end
-        end
-        @multipart = nil
-        @index = options[:index] || options[:child_index]
-      end
-
-      (field_helpers - [:label, :check_box, :radio_button, :fields_for, :hidden_field, :file_field]).each do |selector|
-        class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
-          def #{selector}(method, options = {})  # def text_field(method, options = {})
-            @template.send(                      #   @template.send(
-              #{selector.inspect},               #     "text_field",
-              @object_name,                      #     @object_name,
-              method,                            #     method,
-              objectify_options(options))        #     objectify_options(options))
-          end                                    # end
-        RUBY_EVAL
-      end
-
-      # Creates a scope around a specific model object like form_for, but
-      # doesn't create the form tags themselves. This makes fields_for suitable
-      # for specifying additional model objects in the same form.
-      #
-      # Although the usage and purpose of +field_for+ is similar to +form_for+'s,
-      # its method signature is slightly different. Like +form_for+, it yields
-      # a FormBuilder object associated with a particular model object to a block,
-      # and within the block allows methods to be called on the builder to
-      # generate fields associated with the model object. Fields may reflect
-      # a model object in two ways - how they are named (hence how submitted
-      # values appear within the +params+ hash in the controller) and what
-      # default values are shown when the form the fields appear in is first
-      # displayed. In order for both of these features to be specified independently,
-      # both an object name (represented by either a symbol or string) and the
-      # object itself can be passed to the method separately -
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     First name: <%= person_form.text_field :first_name %>
-      #     Last name : <%= person_form.text_field :last_name %>
-      #
-      #     <%= fields_for :permission, @person.permission do |permission_fields| %>
-      #       Admin?  : <%= permission_fields.check_box :admin %>
-      #     <% end %>
-      #
-      #     <%= person_form.submit %>
-      #   <% end %>
-      #
-      # In this case, the checkbox field will be represented by an HTML +input+
-      # tag with the +name+ attribute <tt>permission[admin]</tt>, and the submitted
-      # value will appear in the controller as <tt>params[:permission][:admin]</tt>.
-      # If <tt>@person.permission</tt> is an existing record with an attribute
-      # +admin+, the initial state of the checkbox when first displayed will
-      # reflect the value of <tt>@person.permission.admin</tt>.
-      #
-      # Often this can be simplified by passing just the name of the model
-      # object to +fields_for+ -
-      #
-      #   <%= fields_for :permission do |permission_fields| %>
-      #     Admin?: <%= permission_fields.check_box :admin %>
-      #   <% end %>
-      #
-      # ...in which case, if <tt>:permission</tt> also happens to be the name of an
-      # instance variable <tt>@permission</tt>, the initial state of the input
-      # field will reflect the value of that variable's attribute <tt>@permission.admin</tt>.
-      #
-      # Alternatively, you can pass just the model object itself (if the first
-      # argument isn't a string or symbol +fields_for+ will realize that the
-      # name has been omitted) -
-      #
-      #   <%= fields_for @person.permission do |permission_fields| %>
-      #     Admin?: <%= permission_fields.check_box :admin %>
-      #   <% end %>
-      #
-      # and +fields_for+ will derive the required name of the field from the
-      # _class_ of the model object, e.g. if <tt>@person.permission</tt>, is
-      # of class +Permission+, the field will still be named <tt>permission[admin]</tt>.
-      #
-      # Note: This also works for the methods in FormOptionHelper and
-      # DateHelper that are designed to work with an object as base, like
-      # FormOptionHelper#collection_select and DateHelper#datetime_select.
-      #
-      # === Nested Attributes Examples
-      #
-      # When the object belonging to the current scope has a nested attribute
-      # writer for a certain attribute, fields_for will yield a new scope
-      # for that attribute. This allows you to create forms that set or change
-      # the attributes of a parent object and its associations in one go.
-      #
-      # Nested attribute writers are normal setter methods named after an
-      # association. The most common way of defining these writers is either
-      # with +accepts_nested_attributes_for+ in a model definition or by
-      # defining a method with the proper name. For example: the attribute
-      # writer for the association <tt>:address</tt> is called
-      # <tt>address_attributes=</tt>.
-      #
-      # Whether a one-to-one or one-to-many style form builder will be yielded
-      # depends on whether the normal reader method returns a _single_ object
-      # or an _array_ of objects.
-      #
-      # ==== One-to-one
-      #
-      # Consider a Person class which returns a _single_ Address from the
-      # <tt>address</tt> reader method and responds to the
-      # <tt>address_attributes=</tt> writer method:
-      #
-      #   class Person
-      #     def address
-      #       @address
-      #     end
-      #
-      #     def address_attributes=(attributes)
-      #       # Process the attributes hash
-      #     end
-      #   end
-      #
-      # This model can now be used with a nested fields_for, like so:
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :address do |address_fields| %>
-      #       Street  : <%= address_fields.text_field :street %>
-      #       Zip code: <%= address_fields.text_field :zip_code %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # When address is already an association on a Person you can use
-      # +accepts_nested_attributes_for+ to define the writer method for you:
-      #
-      #   class Person < ActiveRecord::Base
-      #     has_one :address
-      #     accepts_nested_attributes_for :address
-      #   end
-      #
-      # If you want to destroy the associated model through the form, you have
-      # to enable it first using the <tt>:allow_destroy</tt> option for
-      # +accepts_nested_attributes_for+:
-      #
-      #   class Person < ActiveRecord::Base
-      #     has_one :address
-      #     accepts_nested_attributes_for :address, allow_destroy: true
-      #   end
-      #
-      # Now, when you use a form element with the <tt>_destroy</tt> parameter,
-      # with a value that evaluates to +true+, you will destroy the associated
-      # model (eg. 1, '1', true, or 'true'):
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :address do |address_fields| %>
-      #       ...
-      #       Delete: <%= address_fields.check_box :_destroy %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # ==== One-to-many
-      #
-      # Consider a Person class which returns an _array_ of Project instances
-      # from the <tt>projects</tt> reader method and responds to the
-      # <tt>projects_attributes=</tt> writer method:
-      #
-      #   class Person
-      #     def projects
-      #       [@project1, @project2]
-      #     end
-      #
-      #     def projects_attributes=(attributes)
-      #       # Process the attributes hash
-      #     end
-      #   end
-      #
-      # Note that the <tt>projects_attributes=</tt> writer method is in fact
-      # required for fields_for to correctly identify <tt>:projects</tt> as a
-      # collection, and the correct indices to be set in the form markup.
-      #
-      # When projects is already an association on Person you can use
-      # +accepts_nested_attributes_for+ to define the writer method for you:
-      #
-      #   class Person < ActiveRecord::Base
-      #     has_many :projects
-      #     accepts_nested_attributes_for :projects
-      #   end
-      #
-      # This model can now be used with a nested fields_for. The block given to
-      # the nested fields_for call will be repeated for each instance in the
-      # collection:
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :projects do |project_fields| %>
-      #       <% if project_fields.object.active? %>
-      #         Name: <%= project_fields.text_field :name %>
-      #       <% end %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # It's also possible to specify the instance to be used:
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <% @person.projects.each do |project| %>
-      #       <% if project.active? %>
-      #         <%= person_form.fields_for :projects, project do |project_fields| %>
-      #           Name: <%= project_fields.text_field :name %>
-      #         <% end %>
-      #       <% end %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # Or a collection to be used:
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :projects, @active_projects do |project_fields| %>
-      #       Name: <%= project_fields.text_field :name %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # If you want to destroy any of the associated models through the
-      # form, you have to enable it first using the <tt>:allow_destroy</tt>
-      # option for +accepts_nested_attributes_for+:
-      #
-      #   class Person < ActiveRecord::Base
-      #     has_many :projects
-      #     accepts_nested_attributes_for :projects, allow_destroy: true
-      #   end
-      #
-      # This will allow you to specify which models to destroy in the
-      # attributes hash by adding a form element for the <tt>_destroy</tt>
-      # parameter with a value that evaluates to +true+
-      # (eg. 1, '1', true, or 'true'):
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :projects do |project_fields| %>
-      #       Delete: <%= project_fields.check_box :_destroy %>
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # When a collection is used you might want to know the index of each
-      # object into the array. For this purpose, the <tt>index</tt> method
-      # is available in the FormBuilder object.
-      #
-      #   <%= form_for @person do |person_form| %>
-      #     ...
-      #     <%= person_form.fields_for :projects do |project_fields| %>
-      #       Project #<%= project_fields.index %>
-      #       ...
-      #     <% end %>
-      #     ...
-      #   <% end %>
-      #
-      # Note that fields_for will automatically generate a hidden field
-      # to store the ID of the record. There are circumstances where this
-      # hidden field is not needed and you can pass <tt>include_id: false</tt>
-      # to prevent fields_for from rendering it automatically.
-      def fields_for(record_name, record_object = nil, fields_options = {}, &block)
-        fields_options, record_object = record_object, nil if record_object.is_a?(Hash) && record_object.extractable_options?
-        fields_options[:builder] ||= options[:builder]
-        fields_options[:namespace] = options[:namespace]
-        fields_options[:parent_builder] = self
-
-        case record_name
-        when String, Symbol
-          if nested_attributes_association?(record_name)
-            return fields_for_with_nested_attributes(record_name, record_object, fields_options, block)
-          end
-        else
-          record_object = record_name.is_a?(Array) ? record_name.last : record_name
-          record_name   = model_name_from_record_or_class(record_object).param_key
-        end
-
-        index = if options.has_key?(:index)
-          options[:index]
-        elsif defined?(@auto_index)
-          self.object_name = @object_name.to_s.sub(/\[\]$/,"")
-          @auto_index
-        end
-
-        record_name = index ? "#{object_name}[#{index}][#{record_name}]" : "#{object_name}[#{record_name}]"
-        fields_options[:child_index] = index
-
-        @template.fields_for(record_name, record_object, fields_options, &block)
-      end
-
-      # Returns a label tag tailored for labelling an input field for a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). The text of label will default to the attribute name unless a translation
-      # is found in the current I18n locale (through helpers.label.<modelname>.<attribute>) or you specify it explicitly.
-      # Additional options on the label tag can be passed as a hash with +options+. These options will be tagged
-      # onto the HTML as an HTML element attribute as in the example shown, except for the <tt>:value</tt> option, which is designed to
-      # target labels for radio_button tags (where the value is used in the ID of the input tag).
-      #
-      # ==== Examples
-      #   label(:post, :title)
-      #   # => <label for="post_title">Title</label>
-      #
-      # You can localize your labels based on model and attribute names.
-      # For example you can define the following in your locale (e.g. en.yml)
-      #
-      #   helpers:
-      #     label:
-      #       post:
-      #         body: "Write your entire text here"
-      #
-      # Which then will result in
-      #
-      #   label(:post, :body)
-      #   # => <label for="post_body">Write your entire text here</label>
-      #
-      # Localization can also be based purely on the translation of the attribute-name
-      # (if you are using ActiveRecord):
-      #
-      #   activerecord:
-      #     attributes:
-      #       post:
-      #         cost: "Total cost"
-      #
-      #   label(:post, :cost)
-      #   # => <label for="post_cost">Total cost</label>
-      #
-      #   label(:post, :title, "A short title")
-      #   # => <label for="post_title">A short title</label>
-      #
-      #   label(:post, :title, "A short title", class: "title_label")
-      #   # => <label for="post_title" class="title_label">A short title</label>
-      #
-      #   label(:post, :privacy, "Public Post", value: "public")
-      #   # => <label for="post_privacy_public">Public Post</label>
-      #
-      #   label(:post, :terms) do
-      #     'Accept <a href="/terms">Terms</a>.'.html_safe
-      #   end
-      def label(method, text = nil, options = {}, &block)
-        @template.label(@object_name, method, text, objectify_options(options), &block)
-      end
-
-      # Returns a checkbox tag tailored for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). This object must be an instance object (@object) and not a local object.
-      # It's intended that +method+ returns an integer and if that integer is above zero, then the checkbox is checked.
-      # Additional options on the input tag can be passed as a hash with +options+. The +checked_value+ defaults to 1
-      # while the default +unchecked_value+ is set to 0 which is convenient for boolean values.
-      #
-      # ==== Gotcha
-      #
-      # The HTML specification says unchecked check boxes are not successful, and
-      # thus web browsers do not send them. Unfortunately this introduces a gotcha:
-      # if an +Invoice+ model has a +paid+ flag, and in the form that edits a paid
-      # invoice the user unchecks its check box, no +paid+ parameter is sent. So,
-      # any mass-assignment idiom like
-      #
-      #   @invoice.update(params[:invoice])
-      #
-      # wouldn't update the flag.
-      #
-      # To prevent this the helper generates an auxiliary hidden field before
-      # the very check box. The hidden field has the same name and its
-      # attributes mimic an unchecked check box.
-      #
-      # This way, the client either sends only the hidden field (representing
-      # the check box is unchecked), or both fields. Since the HTML specification
-      # says key/value pairs have to be sent in the same order they appear in the
-      # form, and parameters extraction gets the last occurrence of any repeated
-      # key in the query string, that works for ordinary forms.
-      #
-      # Unfortunately that workaround does not work when the check box goes
-      # within an array-like parameter, as in
-      #
-      #   <%= fields_for "project[invoice_attributes][]", invoice, index: nil do |form| %>
-      #     <%= form.check_box :paid %>
-      #     ...
-      #   <% end %>
-      #
-      # because parameter name repetition is precisely what Rails seeks to distinguish
-      # the elements of the array. For each item with a checked check box you
-      # get an extra ghost item with only that attribute, assigned to "0".
-      #
-      # In that case it is preferable to either use +check_box_tag+ or to use
-      # hashes instead of arrays.
-      #
-      #   # Let's say that @post.validated? is 1:
-      #   check_box("post", "validated")
-      #   # => <input name="post[validated]" type="hidden" value="0" />
-      #   #    <input checked="checked" type="checkbox" id="post_validated" name="post[validated]" value="1" />
-      #
-      #   # Let's say that @puppy.gooddog is "no":
-      #   check_box("puppy", "gooddog", {}, "yes", "no")
-      #   # => <input name="puppy[gooddog]" type="hidden" value="no" />
-      #   #    <input type="checkbox" id="puppy_gooddog" name="puppy[gooddog]" value="yes" />
-      #
-      #   check_box("eula", "accepted", { class: 'eula_check' }, "yes", "no")
-      #   # => <input name="eula[accepted]" type="hidden" value="no" />
-      #   #    <input type="checkbox" class="eula_check" id="eula_accepted" name="eula[accepted]" value="yes" />
-      def check_box(method, options = {}, checked_value = "1", unchecked_value = "0")
-        @template.check_box(@object_name, method, objectify_options(options), checked_value, unchecked_value)
-      end
-
-      # Returns a radio button tag for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). If the current value of +method+ is +tag_value+ the
-      # radio button will be checked.
-      #
-      # To force the radio button to be checked pass <tt>checked: true</tt> in the
-      # +options+ hash. You may pass HTML options there as well.
-      #
-      #   # Let's say that @post.category returns "rails":
-      #   radio_button("post", "category", "rails")
-      #   radio_button("post", "category", "java")
-      #   # => <input type="radio" id="post_category_rails" name="post[category]" value="rails" checked="checked" />
-      #   #    <input type="radio" id="post_category_java" name="post[category]" value="java" />
-      #
-      #   radio_button("user", "receive_newsletter", "yes")
-      #   radio_button("user", "receive_newsletter", "no")
-      #   # => <input type="radio" id="user_receive_newsletter_yes" name="user[receive_newsletter]" value="yes" />
-      #   #    <input type="radio" id="user_receive_newsletter_no" name="user[receive_newsletter]" value="no" checked="checked" />
-      def radio_button(method, tag_value, options = {})
-        @template.radio_button(@object_name, method, tag_value, objectify_options(options))
-      end
-
-      # Returns a hidden input tag tailored for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). Additional options on the input tag can be passed as a
-      # hash with +options+. These options will be tagged onto the HTML as an HTML element attribute as in the example
-      # shown.
-      #
-      # ==== Examples
-      #   hidden_field(:signup, :pass_confirm)
-      #   # => <input type="hidden" id="signup_pass_confirm" name="signup[pass_confirm]" value="#{@signup.pass_confirm}" />
-      #
-      #   hidden_field(:post, :tag_list)
-      #   # => <input type="hidden" id="post_tag_list" name="post[tag_list]" value="#{@post.tag_list}" />
-      #
-      #   hidden_field(:user, :token)
-      #   # => <input type="hidden" id="user_token" name="user[token]" value="#{@user.token}" />
-      #
-      def hidden_field(method, options = {})
-        @emitted_hidden_id = true if method == :id
-        @template.hidden_field(@object_name, method, objectify_options(options))
-      end
-
-      # Returns a file upload input tag tailored for accessing a specified attribute (identified by +method+) on an object
-      # assigned to the template (identified by +object+). Additional options on the input tag can be passed as a
-      # hash with +options+. These options will be tagged onto the HTML as an HTML element attribute as in the example
-      # shown.
-      #
-      # Using this method inside a +form_for+ block will set the enclosing form's encoding to <tt>multipart/form-data</tt>.
-      #
-      # ==== Options
-      # * Creates standard HTML attributes for the tag.
-      # * <tt>:disabled</tt> - If set to true, the user will not be able to use this input.
-      # * <tt>:multiple</tt> - If set to true, *in most updated browsers* the user will be allowed to select multiple files.
-      # * <tt>:accept</tt> - If set to one or multiple mime-types, the user will be suggested a filter when choosing a file. You still need to set up model validations.
-      #
-      # ==== Examples
-      #   file_field(:user, :avatar)
-      #   # => <input type="file" id="user_avatar" name="user[avatar]" />
-      #
-      #   file_field(:post, :image, :multiple => true)
-      #   # => <input type="file" id="post_image" name="post[image]" multiple="true" />
-      #
-      #   file_field(:post, :attached, accept: 'text/html')
-      #   # => <input accept="text/html" type="file" id="post_attached" name="post[attached]" />
-      #
-      #   file_field(:post, :image, accept: 'image/png,image/gif,image/jpeg')
-      #   # => <input type="file" id="post_image" name="post[image]" accept="image/png,image/gif,image/jpeg" />
-      #
-      #   file_field(:attachment, :file, class: 'file_input')
-      #   # => <input type="file" id="attachment_file" name="attachment[file]" class="file_input" />
-      def file_field(method, options = {})
-        self.multipart = true
-        @template.file_field(@object_name, method, objectify_options(options))
-      end
-
-      # Add the submit button for the given form. When no value is given, it checks
-      # if the object is a new resource or not to create the proper label:
-      #
-      #   <%= form_for @post do |f| %>
-      #     <%= f.submit %>
-      #   <% end %>
-      #
-      # In the example above, if @post is a new record, it will use "Create Post" as
-      # submit button label, otherwise, it uses "Update Post".
-      #
-      # Those labels can be customized using I18n, under the helpers.submit key and accept
-      # the %{model} as translation interpolation:
-      #
-      #   en:
-      #     helpers:
-      #       submit:
-      #         create: "Create a %{model}"
-      #         update: "Confirm changes to %{model}"
-      #
-      # It also searches for a key specific for the given object:
-      #
-      #   en:
-      #     helpers:
-      #       submit:
-      #         post:
-      #           create: "Add %{model}"
-      #
-      def submit(value=nil, options={})
-        value, options = nil, value if value.is_a?(Hash)
-        value ||= submit_default_value
-        @template.submit_tag(value, options)
-      end
-
-      # Add the submit button for the given form. When no value is given, it checks
-      # if the object is a new resource or not to create the proper label:
-      #
-      #   <%= form_for @post do |f| %>
-      #     <%= f.button %>
-      #   <% end %>
-      #
-      # In the example above, if @post is a new record, it will use "Create Post" as
-      # button label, otherwise, it uses "Update Post".
-      #
-      # Those labels can be customized using I18n, under the helpers.submit key
-      # (the same as submit helper) and accept the %{model} as translation interpolation:
-      #
-      #   en:
-      #     helpers:
-      #       submit:
-      #         create: "Create a %{model}"
-      #         update: "Confirm changes to %{model}"
-      #
-      # It also searches for a key specific for the given object:
-      #
-      #   en:
-      #     helpers:
-      #       submit:
-      #         post:
-      #           create: "Add %{model}"
-      #
-      # ==== Examples
-      #   button("Create a post")
-      #   # => <button name='button' type='submit'>Create post</button>
-      #
-      #   button do
-      #     content_tag(:strong, 'Ask me!')
-      #   end
-      #   # => <button name='button' type='submit'>
-      #   #      <strong>Ask me!</strong>
-      #   #    </button>
-      #
-      def button(value = nil, options = {}, &block)
-        value, options = nil, value if value.is_a?(Hash)
-        value ||= submit_default_value
-        @template.button_tag(value, options, &block)
-      end
-
-      def emitted_hidden_id?
-        @emitted_hidden_id ||= nil
-      end
-
-      private
-        def objectify_options(options)
-          @default_options.merge(options.merge(object: @object))
-        end
-
-        def submit_default_value
-          object = convert_to_model(@object)
-          key    = object ? (object.persisted? ? :update : :create) : :submit
-
-          model = if object.class.respond_to?(:model_name)
-            object.class.model_name.human
-          else
-            @object_name.to_s.humanize
-          end
-
-          defaults = []
-          defaults << :"helpers.submit.#{object_name}.#{key}"
-          defaults << :"helpers.submit.#{key}"
-          defaults << "#{key.to_s.humanize} #{model}"
-
-          I18n.t(defaults.shift, model: model, default: defaults)
-        end
-
-        def nested_attributes_association?(association_name)
-          @object.respond_to?("#{association_name}_attributes=")
-        end
-
-        def fields_for_with_nested_attributes(association_name, association, options, block)
-          name = "#{object_name}[#{association_name}_attributes]"
-          association = convert_to_model(association)
-
-          if association.respond_to?(:persisted?)
-            association = [association] if @object.send(association_name).respond_to?(:to_ary)
-          elsif !association.respond_to?(:to_ary)
-            association = @object.send(association_name)
-          end
-
-          if association.respond_to?(:to_ary)
-            explicit_child_index = options[:child_index]
-            output = ActiveSupport::SafeBuffer.new
-            association.each do |child|
-              options[:child_index] = nested_child_index(name) unless explicit_child_index
-              output << fields_for_nested_model("#{name}[#{options[:child_index]}]", child, options, block)
-            end
-            output
-          elsif association
-            fields_for_nested_model(name, association, options, block)
-          end
-        end
-
-        def fields_for_nested_model(name, object, fields_options, block)
-          object = convert_to_model(object)
-          emit_hidden_id = object.persisted? && fields_options.fetch(:include_id) {
-            options.fetch(:include_id, true)
-          }
-
-          @template.fields_for(name, object, fields_options) do |f|
-            output = @template.capture(f, &block)
-            output.concat f.hidden_field(:id) if output && emit_hidden_id && !f.emitted_hidden_id?
-            output
-          end
-        end
-
-        def nested_child_index(name)
-          @nested_child_index[name] ||= -1
-          @nested_child_index[name] += 1
-        end
-    end
-  end
-
-  ActiveSupport.on_load(:action_view) do
-    cattr_accessor(:default_form_builder) { ::ActionView::Helpers::FormBuilder }
-  end
-end