Add configuration to treat content as a slot

lib/view_component/base.rb

@@ -103,6 +103,13 @@ def render_in(view_context, &block)
       @__vc_content_evaluated = false
       @__vc_render_in_block = block
 
+      if self.class.send(:__vc_content_is_a_slot?)
+        @__vc_content_evaluated = true
+        if __vc_render_in_block_provided?
+          view_context.capture(self, &@__vc_render_in_block)
+        end
+      end
+
       before_render
 
       if render?
@@ -549,6 +556,10 @@ def render_template_for(variant = nil, format = nil)
           child.instance_variable_set(:@__vc_ancestor_calls, vc_ancestor_calls)
         end
 
+        if defined?(@__vc_content_is_a_slot)
+          child.instance_variable_set(:@__vc_content_is_a_slot, @__vc_content_is_a_slot)
+        end
+
         super
       end
 
@@ -687,6 +698,19 @@ def initialize_parameters
       def provided_collection_parameter
         @provided_collection_parameter ||= nil
       end
+
+      def __vc_content_is_a_slot?
+        defined?(@__vc_content_is_a_slot) && @__vc_content_is_a_slot
+      end
+
+      def content_is_a_slot!
+        @__vc_content_is_a_slot = true
+        renders_one :content
+      end
+
+      def do_not_use_content_as_a_slot!
+        @__vc_content_is_a_slot = false
+      end
     end
 
     ActiveSupport.run_load_hooks(:view_component, self)

lib/view_component/slotable.rb

@@ -298,8 +298,10 @@ def define_slot(slot_name, collection:, callable:)
       end
 
       def validate_plural_slot_name(slot_name)
-        if RESERVED_NAMES[:plural].include?(slot_name.to_sym)
-          raise ReservedPluralSlotNameError.new(name, slot_name)
+        if slot_name.to_sym == :contents && !__vc_content_is_a_slot?
+          if RESERVED_NAMES[:plural].include?(slot_name.to_sym)
+            raise ReservedPluralSlotNameError.new(name, slot_name)
+          end
         end
 
         raise_if_slot_name_uncountable(slot_name)
@@ -309,12 +311,12 @@ def validate_plural_slot_name(slot_name)
       end
 
       def validate_singular_slot_name(slot_name)
-        if slot_name.to_sym == :content
+        if slot_name.to_sym == :content && !__vc_content_is_a_slot?
           raise ContentSlotNameError.new(name)
-        end
-
-        if RESERVED_NAMES[:singular].include?(slot_name.to_sym)
-          raise ReservedSingularSlotNameError.new(name, slot_name)
+        elsif !__vc_content_is_a_slot?
+          if RESERVED_NAMES[:singular].include?(slot_name.to_sym)
+            raise ReservedSingularSlotNameError.new(name, slot_name)
+          end
         end
 
         raise_if_slot_conflicts_with_call(slot_name)

test/sandbox/app/components/content_as_slot_component.html.erb

@@ -0,0 +1,5 @@
+<div>
+  <% if content? %>
+    <%= content %>
+  <% end %>
+</div>

test/sandbox/app/components/content_as_slot_component.rb

@@ -0,0 +1,3 @@
+class ContentAsSlotComponent < ViewComponent::Base
+  content_is_a_slot!
+end

test/sandbox/app/components/content_not_a_slot_component.rb

@@ -0,0 +1,3 @@
+class ContentNotASlotComponent < ViewComponent::Base
+  do_not_use_content_as_a_slot!
+end

test/sandbox/test/slotable_test.rb

@@ -819,4 +819,62 @@ def test_overridden_slot_name_can_be_inherited
   def test_slot_name_methods_are_not_shared_accross_components
     assert_not_equal SlotsComponent.instance_method(:title).owner, SlotNameOverrideComponent::OtherComponent.instance_method(:title).owner
   end
+
+  def test_content_as_a_slot_component
+    component = ContentAsSlotComponent.new
+    render_inline(component) do |c|
+      c.with_content do
+        "The truth is out there"
+      end
+    end
+
+    assert component.content?
+    assert_selector "div", text: "The truth is out there"
+  end
+
+  def test_content_as_a_slot_component_with_content
+    component = ContentAsSlotComponent.new
+    component.with_content do
+      "The truth is out there"
+    end
+    render_inline(component)
+
+    assert component.content?
+    assert_selector "div", text: "The truth is out there"
+  end
+
+  def test_content_as_a_slot_inheritance
+    new_component_class = Class.new(ContentAsSlotComponent)
+    assert new_component_class.send(:__vc_content_is_a_slot?)
+  end
+
+  def test_content_is_not_a_slot
+    new_component_class = Class.new(SlotsComponent) do
+      do_not_use_content_as_a_slot!
+    end
+    refute new_component_class.send(:__vc_content_is_a_slot?)
+
+    render_inline(SlotsComponent.new) do |component|
+      component.with_title do
+        "This is my title!"
+      end
+
+      component.with_subtitle do
+        "This is my subtitle!"
+      end
+
+      component.with_footer do
+        "This is the footer"
+      end
+    end
+
+    assert_text "No tabs provided"
+    assert_text "No items provided"
+  end
+
+  def test_content_is_not_a_slot_inheritance
+    refute ContentNotASlotComponent.send(:__vc_content_is_a_slot?)
+    new_component_class = Class.new(ContentNotASlotComponent)
+    refute new_component_class.send(:__vc_content_is_a_slot?)
+  end
 end