Add support to render subtitle as slot from title component

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## [Unreleased]
 
+- Added support to render subtitle as slot from `Bulma::TitleComponent`
 - Added support to specify HTML tag to use for `Bulma::SubtitleComponent`
 - Updated `Bulma::TitleComponent` previews to use helper method
 - Updated `Bulma::ImageComponent` previews to use Ruby logo

app/components/bulma/title_component.rb

@@ -2,6 +2,8 @@
 
 module Bulma
   class TitleComponent < Component
+    renders_one :subtitle, SubtitleComponent
+
     def initialize(title = nil, as: :h1, size: 1)
       raise ArgumentError, "invalid value to size" if size > 6
 
@@ -11,10 +13,8 @@ def initialize(title = nil, as: :h1, size: 1)
     end
 
     def call
-      content_tag @as, @title || content, class: class_names(
-        "title",
-        "is-#{@size}"
-      )
+      concat content_tag(@as, @title || content, class: class_names("title", "is-#{@size}"))
+      concat subtitle
     end
   end
 end

spec/components/bulma/title_component_spec.rb

@@ -30,4 +30,10 @@
       described_class.new(size: 999)
     }.to raise_error ArgumentError, /invalid value to size/
   end
+
+  it "allows to render a subtitle" do
+    render_inline(described_class.new("Title")) { _1.with_subtitle "Subtitle" }
+
+    expect(page).to have_css "p.subtitle", text: "Subtitle"
+  end
 end