1 files changed, 119 insertions, 0 deletions
diff --git a/actionview/lib/action_view/helpers/tags/collection_helpers.rb b/actionview/lib/action_view/helpers/tags/collection_helpers.rb
new file mode 100644
index 0000000000..e1ad11bff8
--- /dev/null
+++ b/actionview/lib/action_view/helpers/tags/collection_helpers.rb
@@ -0,0 +1,119 @@
+# frozen_string_literal: true
+
+module ActionView
+  module Helpers
+    module Tags # :nodoc:
+      module CollectionHelpers # :nodoc:
+        class Builder # :nodoc:
+          attr_reader :object, :text, :value
+
+          def initialize(template_object, object_name, method_name, object,
+                         sanitized_attribute_name, text, value, input_html_options)
+            @template_object = template_object
+            @object_name = object_name
+            @method_name = method_name
+            @object = object
+            @sanitized_attribute_name = sanitized_attribute_name
+            @text = text
+            @value = value
+            @input_html_options = input_html_options
+          end
+
+          def label(label_html_options = {}, &block)
+            html_options = @input_html_options.slice(:index, :namespace).merge(label_html_options)
+            html_options[:for] ||= @input_html_options[:id] if @input_html_options[:id]
+
+            @template_object.label(@object_name, @sanitized_attribute_name, @text, html_options, &block)
+          end
+        end
+
+        def initialize(object_name, method_name, template_object, collection, value_method, text_method, options, html_options)
+          @collection   = collection
+          @value_method = value_method
+          @text_method  = text_method
+          @html_options = html_options
+
+          super(object_name, method_name, template_object, options)
+        end
+
+        private
+
+          def instantiate_builder(builder_class, item, value, text, html_options)
+            builder_class.new(@template_object, @object_name, @method_name, item,
+                              sanitize_attribute_name(value), text, value, html_options)
+          end
+
+          # Generate default options for collection helpers, such as :checked and
+          # :disabled.
+          def default_html_options_for_collection(item, value)
+            html_options = @html_options.dup
+
+            [:checked, :selected, :disabled, :readonly].each do |option|
+              current_value = @options[option]
+              next if current_value.nil?
+
+              accept = if current_value.respond_to?(:call)
+                current_value.call(item)
+              else
+                Array(current_value).map(&:to_s).include?(value.to_s)
+              end
+
+              if accept
+                html_options[option] = true
+              elsif option == :checked
+                html_options[option] = false
+              end
+            end
+
+            html_options[:object] = @object
+            html_options
+          end
+
+          def sanitize_attribute_name(value)
+            "#{sanitized_method_name}_#{sanitized_value(value)}"
+          end
+
+          def render_collection
+            @collection.map do |item|
+              value = value_for_collection(item, @value_method)
+              text  = value_for_collection(item, @text_method)
+              default_html_options = default_html_options_for_collection(item, value)
+              additional_html_options = option_html_attributes(item)
+
+              yield item, value, text, default_html_options.merge(additional_html_options)
+            end.join.html_safe
+          end
+
+          def render_collection_for(builder_class, &block)
+            options = @options.stringify_keys
+            rendered_collection = render_collection do |item, value, text, default_html_options|
+              builder = instantiate_builder(builder_class, item, value, text, default_html_options)
+
+              if block_given?
+                @template_object.capture(builder, &block)
+              else
+                render_component(builder)
+              end
+            end
+
+            # Prepend a hidden field to make sure something will be sent back to the
+            # server if all radio buttons are unchecked.
+            if options.fetch("include_hidden", true)
+              hidden_field + rendered_collection
+            else
+              rendered_collection
+            end
+          end
+
+          def hidden_field
+            hidden_name = @html_options[:name] || hidden_field_name
+            @template_object.hidden_field_tag(hidden_name, "", id: nil)
+          end
+
+          def hidden_field_name
+            "#{tag_name(false, @options[:index])}"
+          end
+      end
+    end
+  end
+end