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• List of pre-built components

Pre-built components: WithForm

Compony::Components::WithForm is the abstract base for components that render and submit a form. It is twinned with a Form component: WithForm provides the route, authorization and resource handling; the Form provides the inputs and param schema. New and Edit both inherit from WithForm — you rarely subclass it directly, but understanding the twinning explains how they work.

A WithForm component may be resourceful (New/Edit are) but does not have to be.

How the twinning works

• form_comp returns the Form instance, built lazily. It defaults to the component named Form in the same family, instantiated with this component as parent_comp and passed submit_verb, submit_path and cancancan_action.
• The Form renders inside this component's content (e.g. New/Edit do concat form_comp.render(controller, data: @data)).
• The form's <form> posts back to submit_path using submit_verb; that same component handles the submit verb (POST for New, PATCH for Edit) and runs the resourceful lifecycle (assign_attributes → store_data → respond).

DSL methods

Method	Signature	Description
submit_verb	submit_verb(:patch)	HTTP verb the twinned form submits with. Mandatory (New sets :post, Edit :patch).
form_comp_class	form_comp_class(Components::Users::SignupForm)	Use a specific Form class instead of the same-family Form.
submit_path	submit_path { Compony.path(:create, :users) }	Override where the form submits. Block is given the controller; defaults to this component's own path.
form_cancancan_action	form_cancancan_action(:edit)	CanCanCan action used by the Form for per-field permitted_attributes (New sets :new, Edit :edit). Pass nil to disable per-field auth.
form_comp	form_comp	(Not DSL — a reader.) The Form instance; override in a subclass for full control.

Example: a custom non-default form

class Components::Users::Signup < Compony::Components::New
  setup do
    standalone path: 'signup' do
      skip_authentication!
      verb :get  do authorize { true } end
      verb :post do authorize { true } end
    end
    form_comp_class Components::Users::SignupForm   # not the default Users::Form
    on_created_redirect_path { Compony.path(:show, @data) }
  end
end

class Components::Users::SignupForm < Compony::Components::Form
  setup do
    form_fields do
      concat field(:email)
      concat pw_field(:password)
    end
    schema_field :email
    schema_pw_field :password
  end
end

For the full submit/redirect behavior see New and Edit; for the form input/schema DSL see Form; for the lifecycle hooks see Resourceful. Multi-step and clone flows that reuse this machinery are in Real-world patterns.