Module: Guardrails::Lookbook::PanelRegistration

Defined in:
lib/guardrails/lookbook/panel_registration.rb

Overview

Registers a ‘:guardrails` Lookbook panel that renders ComponentReport findings inline next to each preview. The Railtie calls `register!` at app boot when `defined?(::Lookbook)`, so users no longer need to wire the panel by hand.

Extracted from the Railtie so the registration logic and the locals lambda are unit-testable without booting Rails — pass a stub ‘lookbook` and the assertions can inspect what got registered.

Constant Summary collapse

VIEW_PATH =

The gem ships the panel partial inside ‘lib/guardrails/lookbook/views/`. Adding that dir to ActionView’s view paths means the standard Rails partial-resolution machinery finds ‘lookbook_panels/_guardrails.html.erb` without users having to copy it into their app.

File.expand_path("views", __dir__)

Class Method Summary collapse

Class Method Details

.append_view_path(view_consumer = nil) ⇒ Object

APPEND, not prepend — the host’s ‘app/views` must keep precedence so that `app/views/lookbook_panels/_guardrails.html.erb` in the host wins over the gem’s bundled default. Prepending would flip that and silently break the documented override mechanism.



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# File 'lib/guardrails/lookbook/panel_registration.rb', line 33

def append_view_path(view_consumer = nil)
  target = view_consumer || (defined?(::ActionController::Base) ? ::ActionController::Base : nil)
  return unless target&.respond_to?(:append_view_path)

  target.append_view_path(VIEW_PATH)
end

.component_class_name_from(preview_class_name) ⇒ Object

The preview class for a ViewComponent is conventionally ‘<Component>Preview` — Lookbook itself relies on this in `PreviewEntity#guess_render_targets`. Strip the suffix to get the component class name ComponentReport expects. If there’s no ‘Preview` suffix we can’t infer the target component, so we punt rather than guess.



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# File 'lib/guardrails/lookbook/panel_registration.rb', line 86

def component_class_name_from(preview_class_name)
  return nil unless preview_class_name.to_s.end_with?("Preview")

  preview_class_name.to_s.chomp("Preview")
end

.preview_class_name_from(data) ⇒ Object

Lookbook’s inspector_data exposes the current preview’s class via data.preview.preview_class_name (2.x) or data.preview.preview_class.name (older). Probe defensively rather than hardcoding one path.



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# File 'lib/guardrails/lookbook/panel_registration.rb', line 67

def preview_class_name_from(data)
  return nil if data.nil?

  if data.respond_to?(:preview) && data.preview
    preview = data.preview
    return preview.preview_class_name if preview.respond_to?(:preview_class_name)
    return preview.preview_class.name if preview.respond_to?(:preview_class)
  end
  return data.preview_class.name if data.respond_to?(:preview_class)

  nil
end

.register!(lookbook: ::Lookbook, view_consumer: nil) ⇒ Object 



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# File 'lib/guardrails/lookbook/panel_registration.rb', line 24

def register!(lookbook: ::Lookbook, view_consumer: nil)
  append_view_path(view_consumer)
  register_panel(lookbook)
end

.register_panel(lookbook = ::Lookbook) ⇒ Object

Lookbook 2.x exposes ‘Lookbook.add_panel(name, partial_path, opts)` at the module level. opts can be a callable that receives the inspector_data Store at render time and returns a Hash of locals for the partial. The pre-2.x API of `config.lookbook.preview_inspector.panels.add` doesn’t exist.



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# File 'lib/guardrails/lookbook/panel_registration.rb', line 45

def register_panel(lookbook = ::Lookbook)
  return unless lookbook.respond_to?(:add_panel)

  lookbook.add_panel(:guardrails, "lookbook_panels/guardrails", {
    label: "Guardrails",
    locals: ->(data) { { findings: report_for_preview(data) } }
  })
end

.report_for_preview(data) ⇒ Object 



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# File 'lib/guardrails/lookbook/panel_registration.rb', line 54

def report_for_preview(data)
  preview_class_name = preview_class_name_from(data)
  return nil unless preview_class_name

  component_class_name = component_class_name_from(preview_class_name)
  return nil unless component_class_name

  ComponentReport.new(root: ::Rails.root).for(component_class_name)
end