Change `form_with` to generates ids by default

When `form_with` was introduced we disabled the automatic
generation of ids that was enabled in `form_for`. This usually
is not an good idea since labels don't work when the input
doesn't have an id and it made harder to test with Capybara.

You can still disable the automatic generation of ids setting
`config.action_view.form_with_generates_ids` to `false.`

actionview/CHANGELOG.md

+*   Change `form_with` to generates ids by default.
+
+    When `form_with` was introduced we disabled the automatic generation of ids
+    that was enabled in `form_for`. This usually is not an good idea since labels don't work
+    when the input doesn't have an id and it made harder to test with Capybara.
+
+    You can still disable the automatic generation of ids setting `config.action_view.form_with_generates_ids`
+    to `false.`
+
+    *Nick Pezza*
+
 *   Fix issues with `field_error_proc` wrapping `optgroup` and select divider `option`.
 
     Fixes #31088

actionview/lib/action_view/helpers/form_helper.rb

@@ -478,6 +478,8 @@ def apply_form_for_options!(record, object, options) #:nodoc:
 
       mattr_accessor :form_with_generates_remote_forms, default: true
 
+      mattr_accessor :form_with_generates_ids, default: true
+
       # Creates a form tag based on mixing URLs, scopes, or models.
       #
       #   # Using just a URL:
@@ -640,16 +642,6 @@ def apply_form_for_options!(record, object, options) #:nodoc:
       #
       # Where <tt>@document = Document.find(params[:id])</tt>.
       #
-      # When using labels +form_with+ requires setting the id on the field being
-      # labelled:
-      #
-      #   <%= form_with(model: @post) do |form| %>
-      #     <%= form.label :title %>
-      #     <%= form.text_field :title, id: :post_title %>
-      #   <% end %>
-      #
-      # See +label+ for more on how the +for+ attribute is derived.
-      #
       # === Mixing with other form helpers
       #
       # While +form_with+ uses a FormBuilder object it's possible to mix and
@@ -746,7 +738,6 @@ def apply_form_for_options!(record, object, options) #:nodoc:
       #   end
       def form_with(model: nil, scope: nil, url: nil, format: nil, **options)
         options[:allow_method_names_outside_object] = true
-        options[:skip_default_ids] = true
 
         if model
           url ||= polymorphic_path(model, format: format)
@@ -1044,16 +1035,6 @@ def fields_for(record_name, record_object = nil, options = {}, &block)
       # or model is yielded, so any generated field names are prefixed with
       # either the passed scope or the scope inferred from the <tt>:model</tt>.
       #
-      # When using labels +fields+ requires setting the id on the field being
-      # labelled:
-      #
-      #   <%= fields :comment do |fields| %>
-      #     <%= fields.label :body %>
-      #     <%= fields.text_field :body, id: :comment_body %>
-      #   <% end %>
-      #
-      # See +label+ for more on how the +for+ attribute is derived.
-      #
       # === Mixing with other form helpers
       #
       # While +form_with+ uses a FormBuilder object it's possible to mix and
@@ -1072,7 +1053,6 @@ def fields_for(record_name, record_object = nil, options = {}, &block)
       # FormOptionsHelper#collection_select and DateHelper#datetime_select.
       def fields(scope = nil, model: nil, **options, &block)
         options[:allow_method_names_outside_object] = true
-        options[:skip_default_ids] = true
 
         if model
           scope ||= model_name_from_record_or_class(model).param_key
@@ -1676,7 +1656,7 @@ def to_model
       def initialize(object_name, object, template, options)
         @nested_child_index = {}
         @object_name, @object, @template, @options = object_name, object, template, options
-        @default_options = @options ? @options.slice(:index, :namespace, :skip_default_ids, :allow_method_names_outside_object) : {}
+        @default_options = @options ? @options.slice(:index, :namespace, :allow_method_names_outside_object) : {}
 
         convert_to_legacy_options(@options)
 
@@ -1985,7 +1965,6 @@ def fields_for(record_name, record_object = nil, fields_options = {}, &block)
       # See the docs for the <tt>ActionView::FormHelper.fields</tt> helper method.
       def fields(scope = nil, model: nil, **options, &block)
         options[:allow_method_names_outside_object] = true
-        options[:skip_default_ids] = true
 
         convert_to_legacy_options(options)
 

actionview/lib/action_view/helpers/tags/base.rb

@@ -15,7 +15,6 @@ def initialize(object_name, method_name, template_object, options = {})
 
           @object_name.sub!(/\[\]$/, "") || @object_name.sub!(/\[\]\]$/, "]")
           @object = retrieve_object(options.delete(:object))
-          @skip_default_ids = options.delete(:skip_default_ids)
           @allow_method_names_outside_object = options.delete(:allow_method_names_outside_object)
           @options = options
 
@@ -97,7 +96,7 @@ def add_default_name_and_id(options)
             index = name_and_id_index(options)
             options["name"] = options.fetch("name") { tag_name(options["multiple"], index) }
 
-            unless skip_default_ids?
+            if generate_ids?
               options["id"] = options.fetch("id") { tag_id(index) }
               if namespace = options.delete("namespace")
                 options["id"] = options["id"] ? "#{namespace}_#{options['id']}" : namespace
@@ -183,8 +182,8 @@ def name_and_id_index(options)
             end
           end
 
-          def skip_default_ids?
-            @skip_default_ids
+          def generate_ids?
+            ActionView::Helpers::FormHelper.form_with_generates_ids
           end
       end
     end

actionview/lib/action_view/helpers/tags/collection_check_boxes.rb

@@ -12,7 +12,6 @@ class CheckBoxBuilder < Builder # :nodoc:
           def check_box(extra_html_options = {})
             html_options = extra_html_options.merge(@input_html_options)
             html_options[:multiple] = true
-            html_options[:skip_default_ids] = false
             @template_object.check_box(@object_name, @method_name, html_options, @value, nil)
           end
         end

actionview/lib/action_view/helpers/tags/collection_radio_buttons.rb

@@ -11,7 +11,6 @@ class CollectionRadioButtons < Base # :nodoc:
         class RadioButtonBuilder < Builder # :nodoc:
           def radio_button(extra_html_options = {})
             html_options = extra_html_options.merge(@input_html_options)
-            html_options[:skip_default_ids] = false
             @template_object.radio_button(@object_name, @method_name, @value, html_options)
           end
         end

actionview/lib/action_view/helpers/tags/label.rb

@@ -75,10 +75,6 @@ def render(&block)
           def render_component(builder)
             builder.translation
           end
-
-          def skip_default_ids?
-            false # The id is used as the `for` attribute.
-          end
       end
     end
   end

actionview/lib/action_view/helpers/tags/select.rb

@@ -8,7 +8,7 @@ def initialize(object_name, method_name, template_object, choices, options, html
           @choices = block_given? ? template_object.capture { yield || "" } : choices
           @choices = @choices.to_a if @choices.is_a?(Range)
 
-          @html_options = html_options.except(:skip_default_ids, :allow_method_names_outside_object)
+          @html_options = html_options.except(:allow_method_names_outside_object)
 
           super(object_name, method_name, template_object, options)
         end

actionview/lib/action_view/railtie.rb

@@ -28,6 +28,15 @@ class Railtie < Rails::Engine # :nodoc:
       end
     end
 
+    initializer "action_view.form_with_generates_ids" do |app|
+      ActiveSupport.on_load(:action_view) do
+        form_with_generates_ids = app.config.action_view.delete(:form_with_generates_ids)
+        unless form_with_generates_ids.nil?
+          ActionView::Helpers::FormHelper.form_with_generates_ids = form_with_generates_ids
+        end
+      end
+    end
+
     initializer "action_view.logger" do
       ActiveSupport.on_load(:action_view) { self.logger ||= Rails.logger }
     end

guides/source/configuring.md

@@ -578,6 +578,8 @@ Defaults to `'signed cookie'`.
 
 * `config.action_view.form_with_generates_remote_forms` determines whether `form_with` generates remote forms or not. This defaults to `true`.
 
+* `config.action_view.form_with_generates_ids` determines whether `form_with` generates ids on inputs. This defaults to `true`.
+
 ### Configuring Action Mailer
 
 There are a number of settings available on `config.action_mailer`:

railties/lib/rails/application/configuration.rb

@@ -81,6 +81,7 @@ def load_defaults(target_version)
 
           if respond_to?(:action_view)
             action_view.form_with_generates_remote_forms = true
+            action_view.form_with_generates_ids = true
           end
 
         when "5.2"

railties/test/application/configuration_test.rb

@@ -757,6 +757,68 @@ def index
       assert_match(/label/, last_response.body)
     end
 
+    test "form_with can be configured with form_with_generates_ids" do
+      app_file "config/initializers/form_builder.rb", <<-RUBY
+      Rails.configuration.action_view.form_with_generates_ids = false
+      RUBY
+
+      app_file "app/models/post.rb", <<-RUBY
+      class Post
+        include ActiveModel::Model
+        attr_accessor :name
+      end
+      RUBY
+
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
+      class PostsController < ApplicationController
+        def index
+          render inline: "<%= begin; form_with(model: Post.new) {|f| f.text_field(:name)}; rescue => e; e.to_s; end %>"
+        end
+      end
+      RUBY
+
+      add_to_config <<-RUBY
+        routes.prepend do
+          resources :posts
+        end
+      RUBY
+
+      app "development"
+
+      get "/posts"
+
+      assert_no_match(/id=('|")post_name('|")/, last_response.body)
+    end
+
+    test "form_with outputs ids by default" do
+      app_file "app/models/post.rb", <<-RUBY
+      class Post
+        include ActiveModel::Model
+        attr_accessor :name
+      end
+      RUBY
+
+      app_file "app/controllers/posts_controller.rb", <<-RUBY
+      class PostsController < ApplicationController
+        def index
+          render inline: "<%= begin; form_with(model: Post.new) {|f| f.text_field(:name)}; rescue => e; e.to_s; end %>"
+        end
+      end
+      RUBY
+
+      add_to_config <<-RUBY
+        routes.prepend do
+          resources :posts
+        end
+      RUBY
+
+      app "development"
+
+      get "/posts"
+
+      assert_match(/id=('|")post_name('|")/, last_response.body)
+    end
+
     test "form_with can be configured with form_with_generates_remote_forms" do
       app_file "config/initializers/form_builder.rb", <<-RUBY
       Rails.configuration.action_view.form_with_generates_remote_forms = false