feat: make email optional for under-16 participants except applicant

tests/BusProNet/DataProcessor/BookingPayloadBuilderTest.php

@@ -13,7 +13,7 @@ use App\Form\Model\ParticipantDto;
 use PHPUnit\Framework\TestCase;
 
 /**
- * Covers who the <anmelder> block is built from, and the participant email fallback.
+ * Covers who the <anmelder> block is built from, and that a participant's blank email stays blank.
  */
 class BookingPayloadBuilderTest extends TestCase
 {
@@ -69,7 +69,7 @@ class BookingPayloadBuilderTest extends TestCase
         $this->assertArrayNotHasKey('idadresse', $payload['anmelder']);
     }
 
-    public function testParticipantWithoutEmailInheritsTheApplicants(): void
+    public function testParticipantWithoutEmailIsSentWithoutOne(): void
     {
         $bookingDto = $this->createBookingDto();
         $bookingDto->applicantTravels = false;
@@ -78,10 +78,10 @@ class BookingPayloadBuilderTest extends TestCase
 
         $payload = $this->builder->buildCreatePayload($bookingDto, 'BUCHUNG');
 
-        $this->assertSame(
-            'e[email protected]',
-            $payload['teilnehmerliste']['teilnehmer'][0]['kommunikation']['email'],
-            'BusPro rejects a participant without a Mail-Adresse with 650, but accepts a shared one'
+        $this->assertArrayNotHasKey(
+            'email',
+            $payload['teilnehmerliste']['teilnehmer'][0]['kommunikation'],
+            'BusPro accepts a participant without a Mail-Adresse; the applicant\'s must not be borrowed'
         );
     }