Allow preselecting a grouped option

app/presenters/hotwire_combobox/component.rb

@@ -243,7 +243,7 @@ def prefilled_display
       if async_src && associated_object
         associated_object.to_combobox_display
       elsif hidden_field_value
-        options.find { |option| option.value == hidden_field_value }&.autocompletable_as
+        options.find_by_value(hidden_field_value)&.autocompletable_as
       end
     end
 

app/presenters/hotwire_combobox/listbox/group.rb

@@ -1,6 +1,8 @@
 require "securerandom"
 
 class HotwireCombobox::Listbox::Group
+  attr_reader :options
+
   def initialize(name, options:)
     @name = name
     @options = options
@@ -17,7 +19,7 @@ def render_in(view)
   end
 
   private
-    attr_reader :name, :options
+    attr_reader :name
 
     def id
       @id ||= SecureRandom.uuid

app/presenters/hotwire_combobox/listbox/item.rb

@@ -1,7 +1,7 @@
 class HotwireCombobox::Listbox::Item
   class << self
     def collection_for(view, options, render_in:, include_blank:, **custom_methods)
-      new(view, options, render_in: render_in, include_blank: include_blank, **custom_methods).items
+      new(view, options, render_in: render_in, include_blank: include_blank, **custom_methods).collection
     end
   end
 
@@ -13,10 +13,10 @@ def initialize(view, options, render_in:, include_blank:, **custom_methods)
     @custom_methods = custom_methods
   end
 
-  def items
+  def collection
     items = groups_or_options
     items.unshift(blank_option) if include_blank.present?
-    items
+    Collection.new items
   end
 
   private
@@ -31,7 +31,7 @@ def groups_or_options
     end
 
     def grouped?
-      key, value = options.to_a.first
+      _key, value = options.to_a.first
       value.is_a? Array
     end
 
@@ -43,8 +43,12 @@ def create_listbox_group(options)
     end
 
     def create_listbox_options(options)
-      options.map do |option|
-        HotwireCombobox::Listbox::Option.new **option_attrs(option)
+      if options.first.is_a? HotwireCombobox::Listbox::Option
+        options
+      else
+        options.map do |option|
+          HotwireCombobox::Listbox::Option.new **option_attrs(option)
+        end
       end
     end
 

app/presenters/hotwire_combobox/listbox/item/collection.rb

@@ -0,0 +1,14 @@
+class HotwireCombobox::Listbox::Item::Collection < Array
+  def find_by_value(value)
+    if grouped?
+      flat_map { |item| item.options }.find { |option| option.value == value }
+    else
+      find { |option| option.value == value }
+    end
+  end
+
+  private
+    def grouped?
+      first.is_a? HotwireCombobox::Listbox::Group
+    end
+end

lib/hotwire_combobox/helper.rb

@@ -26,16 +26,12 @@ def hw_combobox_options(
           include_blank: nil,
           display: :to_combobox_display,
           **custom_methods)
-      if options.first.is_a? HotwireCombobox::Listbox::Option
-        options
-      else
-        HotwireCombobox::Listbox::Item.collection_for \
-          self,
-          options,
-          render_in: render_in,
-          include_blank: include_blank,
-          **custom_methods.merge(display: display)
-      end
+      HotwireCombobox::Listbox::Item.collection_for \
+        self,
+        options,
+        render_in: render_in,
+        include_blank: include_blank,
+        **custom_methods.merge(display: display)
     end
 
     def hw_paginated_combobox_options(
@@ -184,7 +180,7 @@ def hw_call_method_or_proc(object, method_or_proc)
     private
       def hw_extract_options_and_src(options_or_src, render_in, include_blank)
         if options_or_src.is_a? String
-          [ [], options_or_src ]
+          [ hw_combobox_options([]), options_or_src ]
         else
           [ hw_combobox_options(options_or_src, render_in: render_in, include_blank: include_blank), nil ]
         end

test/dummy/app/views/comboboxes/grouped_options.html.erb

@@ -14,3 +14,4 @@
 <%= combobox_tag "state", State.all.group_by(&:location), id: "state-field" %>
 <%= combobox_tag "state_but_weird", weird_options, id: "weird-state-field" %>
 <%= combobox_tag "state_with_blank", State.all.group_by(&:location), id: "state-field-with-blank", include_blank: "All" %>
+<%= combobox_tag "preselected", State.all.group_by(&:location), id: "preselected", value: State.first.id %>

test/system/hotwire_combobox_test.rb

@@ -1114,6 +1114,10 @@ class HotwireComboboxTest < ApplicationSystemTestCase
     assert_selected_option_with text: "All"
     type_in_combobox "#state-field-with-blank", :down
     assert_selected_option_with text: "Alabama"
+
+    assert_combobox_display_and_value "#preselected", "Alabama", states(:alabama).id
+    open_combobox "#preselected"
+    assert_selected_option_with text: "Alabama"
   end
 
   test "preselected morph" do