Scope transfer destinations to the source event's kind

A facilitator training only transfers to another facilitator training, and a
non-training only to another non-training, so the destination picker matches
the source event's facilitator_training flag.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: maebeale

app/controllers/event_registrations_controller.rb

@@ -358,10 +358,12 @@ def set_event_registration
     @event_registration = EventRegistration.includes({ registrant: [ :user, { affiliations: :organization } ] }, { event: [ :location, :event_forms ] }, :organizations, comments: [ :created_by, :updated_by ]).find(params[:id])
   end
 
-  # Events a registrant can be transferred into: any published event other than
-  # the one they're transferring out of, most recent first.
+  # Events a registrant can be transferred into: published events of the same
+  # kind as the one they're leaving — a facilitator training only transfers to
+  # another facilitator training, and a non-training only to another
+  # non-training — excluding the source event, most recent first.
   def transfer_destination_events
-    Event.where(published: true)
+    Event.where(published: true, facilitator_training: @event_registration.event.facilitator_training)
          .where.not(id: @event_registration.event_id)
          .order(start_date: :desc)
   end

app/views/event_registrations/transfer.html.erb

@@ -44,6 +44,9 @@
               include_blank: "Select an event…",
               required: true,
               class: "w-full rounded-lg border border-gray-300 px-3 py-2 text-sm text-gray-700 shadow-sm focus:border-blue-500 focus:ring focus:ring-blue-200 focus:outline-none" %>
+        <p class="mt-1.5 text-xs text-gray-500">
+          Only <%= source.event.facilitator_training? ? "other facilitator trainings" : "other (non-training) events" %> are shown.
+        </p>
       </div>
 
       <div class="flex items-center gap-3 border-t border-gray-200 pt-4">

spec/requests/event_registrations_spec.rb

@@ -396,15 +396,29 @@ def toggle_day(field, value)
       let!(:source) { create(:event_registration, event: event, status: "transferred_out") }
 
       describe "GET /event_registrations/:id/transfer" do
-        it "renders the destination picker, excluding the source event" do
-          other = create(:event, title: "Destination Event", published: true)
+        it "offers same-kind events, excluding the source and the other kind" do
+          same_kind = create(:event, title: "Destination Event", published: true, facilitator_training: false)
+          other_kind = create(:event, title: "A Facilitator Training", published: true, facilitator_training: true)
 
           get transfer_event_registration_path(source)
 
           expect(response).to have_http_status(:success)
           expect(response.body).to include("Destination Event")
-          # The source event isn't offered as a transfer destination.
+          # The source event and the opposite kind aren't offered as destinations.
           expect(response.body).not_to include("<option value=\"#{event.id}\"")
+          expect(response.body).not_to include("<option value=\"#{other_kind.id}\"")
+        end
+
+        it "offers only other facilitator trainings when transferring out of one" do
+          training = create(:event, title: "Source Training", facilitator_training: true)
+          training_source = create(:event_registration, event: training, status: "transferred_out")
+          another_training = create(:event, title: "Another Training", published: true, facilitator_training: true)
+          non_training = create(:event, title: "A Non-Training Event", published: true, facilitator_training: false)
+
+          get transfer_event_registration_path(training_source)
+
+          expect(response.body).to include("<option value=\"#{another_training.id}\"")
+          expect(response.body).not_to include("<option value=\"#{non_training.id}\"")
         end
       end