Add options contexts to set conventions for more involved definitions

app/models/showcase/options.rb

@@ -1,5 +1,5 @@
 class Showcase::Options
-  include Enumerable
+  include Enumerable, Contexts
 
   def initialize(view_context)
     @view_context = view_context
@@ -9,11 +9,19 @@ def initialize(view_context)
   delegate :empty?, to: :@options
 
   def required(*arguments, **keywords, &block)
-    option(*arguments, **keywords, required: true, &block)
+    if arguments.none?
+      with_options required: true
+    else
+      option(*arguments, **keywords, required: true, &block)
+    end
   end
 
   def optional(*arguments, **keywords, &block)
-    option(*arguments, **keywords, required: false, &block)
+    if arguments.none?
+      with_options required: false
+    else
+      option(*arguments, **keywords, required: false, &block)
+    end
   end
 
   DEFAULT_OMITTED = Object.new

app/models/showcase/options/contexts.rb

@@ -0,0 +1,65 @@
+module Showcase::Options::Contexts
+  class Context < Showcase::Options
+    def initialize(view_context, options, **kwargs)
+      super(view_context)
+      @options = options
+      kwargs.each { instance_variable_set(:"@#{_1}", _2) }
+    end
+  end
+
+  # showcase.options.context :stimulus, controller: :welcome
+  def context(key, **options, &block)
+    context = self.class.contexts.fetch(key)
+    context.new(@view_context, @options, **options).tap { yield _1 if block_given? }
+  end
+
+  module ClassMethods
+    #   Showcase.options.define :stimulus do
+    #     def value(name, ...)
+    #       option("data-#{@controller}-#{name}-value", ...)
+    #     end
+    #   end
+    #
+    #   showcase.options.stimulus controller: :welcome do |o|
+    #     o.value :greeting, default: "Hello"
+    #   end
+    attr_reader :contexts
+
+    def define(key, &block)
+      contexts[key].class_eval(&block) # Lets users reopen an already defined context class.
+    end
+  end
+
+  def self.included(klass)
+    klass.extend ClassMethods
+    klass.instance_variable_set :@contexts, Hash.new { |h,k| h[k] = Class.new Context }
+
+    klass.define :stimulus do
+      def target(name, ...)
+        option(%(data-#{@controller}-target="#{name}"), ...)
+      end
+
+      def value(name, ...)
+        option("data-#{@controller}-#{name}-value", ...)
+      end
+
+      def klass(name, ...)
+        option("data-#{@controller}-#{name}-class", ...)
+      end
+
+      def outlet(name, ...)
+        option("data-#{@controller}-#{name}-outlet", ...)
+      end
+
+      def action(name, ...)
+        option(%(data-action="#{name}"), ...)
+      end
+    end
+
+    klass.define :nice_partials do
+      def content_block(*arguments, **options, &block)
+        option(*arguments, **options, type: "Content Block", &block)
+      end
+    end
+  end
+end

lib/showcase.rb

@@ -15,6 +15,10 @@ def self.previews
       Dir.glob("**/*.*", base: File.join(root, previews_path))
     end.uniq
   end
+
+  def self.options
+    Options
+  end
 end
 
 require "showcase/engine" if defined?(Rails::Engine)

test/controllers/showcase/previews_controller_test.rb

@@ -102,9 +102,14 @@ class Showcase::PreviewsControllerTest < Showcase::InternalIntegrationTest
 
     within :section, "Options" do
       assert_table with_rows: [
-        {"Name" => "data-welcome-target", "Required" => "", "Type" => "String", "Default" => "", "Description" => "If the id of the target element must be printed"},
-        {"Name" => "data-welcome-yell-value", "Required" => "", "Type" => "Boolean", "Default" => "false", "Description" => "Whether the hello is to be YELLED"}
+        {"Name" => %(data-welcome-target="greeter"), "Required" => "", "Type" => "String", "Default" => "", "Description" => "If the id of the target element must be printed"},
+        {"Name" => "data-welcome-yell-value", "Required" => "", "Type" => "Boolean", "Default" => "false", "Description" => "Whether the hello is to be YELLED"},
+        {"Name" => "data-welcome-success-class", "Required" => "", "Type" => "String", "Default" => "", "Description" => "The success class to append after greeting"},
+        {"Name" => "data-welcome-list-outlet", "Required" => "", "Type" => "String", "Default" => "", "Description" => "An outlet to append each yelled greeter to"},
+        {"Name" => %(data-action="greet"), "Required" => "", "Type" => "String", "Default" => "", "Description" => "An action to repeat the greeting, if need be"}
       ]
+
+      assert_element "input", count: 3
     end
   end
 end

test/dummy/app/views/showcase/previews/stimulus_controllers/_welcome.html.erb

@@ -14,7 +14,10 @@
   <div data-controller="welcome" data-welcome-yell-value="true">
 <% end %>
 
-<% showcase.options do |o| %>
-  <% o.optional "data-welcome-target", "If the id of the target element must be printed" %>
-  <% o.optional "data-welcome-yell-value", "Whether the hello is to be YELLED", default: false %>
+<% showcase.options.context :stimulus, controller: :welcome do |o| %>
+  <% o.optional.target :greeter, "If the id of the target element must be printed" %>
+  <% o.required.value :yell, "Whether the hello is to be YELLED", default: false %>
+  <% o.required.klass :success, "The success class to append after greeting" %>
+  <% o.required.outlet :list, "An outlet to append each yelled greeter to" %>
+  <% o.optional.action :greet, "An action to repeat the greeting, if need be" %>
 <% end %>