test stable schedule snapshots

backend/tests/Fakes/FakeScheduleRepository.php

@@ -23,7 +23,9 @@ class FakeScheduleRepository implements ScheduleRepository
         foreach ($dto->assignments as $assignmentDto) {
             $assignments[] = new ScheduleAssignment(
                 id: count($assignments) + 1,
-                element: $assignmentDto->element,
+                name: $assignmentDto->name,
+                kind: $assignmentDto->kind,
+                path: $assignmentDto->path,
                 scheduledDate: $assignmentDto->scheduledDate,
                 position: $assignmentDto->position,
             );
@@ -32,7 +34,7 @@ class FakeScheduleRepository implements ScheduleRepository
         $schedule = new Schedule(
             id: $id,
             user: $dto->user,
-            set: $dto->set,
+            setName: $dto->setName,
             elementKind: $dto->elementKind,
             startDate: $dto->startDate,
             targetDate: $dto->targetDate,
@@ -76,7 +78,9 @@ class FakeScheduleRepository implements ScheduleRepository
             function (ScheduleAssignment $assignment): ScheduleAssignment {
                 return new ScheduleAssignment(
                     id: $assignment->getId(),
-                    element: $assignment->getElement(),
+                    name: $assignment->getName(),
+                    kind: $assignment->getKind(),
+                    path: $assignment->getPath(),
                     scheduledDate: $assignment->getScheduledDate(),
                     position: $assignment->getPosition(),
                 );
@@ -87,7 +91,7 @@ class FakeScheduleRepository implements ScheduleRepository
         return new Schedule(
             id: $schedule->getId(),
             user: $schedule->getUser(),
-            set: $schedule->getSet(),
+            setName: $schedule->getSetName(),
             elementKind: $schedule->getElementKind(),
             startDate: $schedule->getStartDate(),
             targetDate: $schedule->getTargetDate(),

backend/tests/Feature/Schedule/ScheduleEndpointTest.php

@@ -5,10 +5,12 @@ namespace Tests\Feature\Schedule;
 use App\Auth\CreateSessionDto;
 use App\Auth\SessionRepository;
 use App\Element\CreateElementDto;
+use App\Element\ElementModel;
 use App\Element\ElementRepository;
 use App\Http\Middleware\AuthMiddleware;
 use App\Set\CreateSetDto;
 use App\Set\Set;
+use App\Set\SetModel;
 use App\Set\SetRepository;
 use App\Shared\ValueObject\EmailAddress;
 use App\User\CreateUserDto;
@@ -17,6 +19,7 @@ use App\User\UserRepository;
 use DateTimeImmutable;
 use DateTimeZone;
 use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\Schema;
 use Illuminate\Testing\TestResponse;
 use Tests\TestCase;
 
@@ -73,7 +76,6 @@ class ScheduleEndpointTest extends TestCase
             'schedule' => [
                 'id' => 1,
                 'set' => [
-                    'id' => $set->getId(),
                     'name' => 'Bible',
                 ],
                 'elementKind' => 'chapter',
@@ -85,8 +87,8 @@ class ScheduleEndpointTest extends TestCase
                         'date' => '2026-08-10',
                         'assignments' => [
                             [
+                                'id' => 1,
                                 'element' => [
-                                    'id' => $chapterOne->getId(),
                                     'name' => 'Chapter 1',
                                     'kind' => 'chapter',
                                     'path' => [
@@ -106,8 +108,8 @@ class ScheduleEndpointTest extends TestCase
                         'date' => '2026-08-12',
                         'assignments' => [
                             [
+                                'id' => 2,
                                 'element' => [
-                                    'id' => $chapterTwo->getId(),
                                     'name' => 'Chapter 1',
                                     'kind' => 'chapter',
                                     'path' => [
@@ -123,12 +125,29 @@ class ScheduleEndpointTest extends TestCase
         ]);
         $this->assertDatabaseHas('schedules', [
             'user_id' => $user->getId(),
-            'set_id' => $set->getId(),
+            'set_name' => 'Bible',
             'element_kind' => 'chapter',
             'start_date' => '2026-08-10',
             'target_date' => '2026-08-12',
         ]);
+        $this->assertDatabaseHas('schedule_assignments', [
+            'schedule_id' => 1,
+            'element_name' => 'Chapter 1',
+            'element_kind' => 'chapter',
+            'element_path' => json_encode([
+                'Genesis',
+                'Creation',
+                'Chapter 1',
+            ]),
+            'scheduled_date' => '2026-08-10',
+            'position' => 1,
+        ]);
         $this->assertDatabaseCount('schedule_assignments', 2);
+        $this->assertFalse(Schema::hasColumn('schedules', 'set_id'));
+        $this->assertFalse(Schema::hasColumn(
+            'schedule_assignments',
+            'element_id',
+        ));
 
         $this->credentialedGet('/api/schedules/1')
             ->assertOk()
@@ -179,7 +198,6 @@ class ScheduleEndpointTest extends TestCase
                     [
                         'id' => 2,
                         'set' => [
-                            'id' => $set->getId(),
                             'name' => 'Course',
                         ],
                         'elementKind' => 'lesson',
@@ -190,7 +208,6 @@ class ScheduleEndpointTest extends TestCase
                     [
                         'id' => 1,
                         'set' => [
-                            'id' => $set->getId(),
                             'name' => 'Course',
                         ],
                         'elementKind' => 'lesson',
@@ -202,6 +219,55 @@ class ScheduleEndpointTest extends TestCase
             ]);
     }
 
+    public function test_it_is_stable_after_sources_change_or_are_deleted(): void
+    {
+        $user = $this->createUser('reader@example.com');
+        $set = $this->createSet($user, 'Original set');
+        $repository = app(ElementRepository::class);
+        $parent = $repository->create(new CreateElementDto(
+            set: $set,
+            name: 'Original parent',
+            kind: 'group',
+            parentElement: null,
+        ));
+        $element = $repository->create(new CreateElementDto(
+            set: $set,
+            name: 'Original item',
+            kind: 'task',
+            parentElement: $parent,
+        ));
+        $this->createSession($user, 'valid-token');
+        $createdResponse = $this->credentialedPost('/api/schedules', [
+            'setId' => $set->getId(),
+            'elementKind' => 'task',
+            'startDate' => '2026-08-10',
+            'targetDate' => '2026-08-10',
+        ])->assertCreated();
+
+        SetModel::query()->whereKey($set->getId())->update([
+            'name' => 'Changed set',
+        ]);
+        ElementModel::query()->whereKey($parent->getId())->update([
+            'name' => 'Changed parent',
+        ]);
+        ElementModel::query()->whereKey($element->getId())->update([
+            'name' => 'Changed item',
+            'kind' => 'changed-kind',
+        ]);
+
+        $this->credentialedGet('/api/schedules/1')
+            ->assertOk()
+            ->assertExactJson($createdResponse->json());
+
+        ElementModel::query()->whereKey($element->getId())->delete();
+        ElementModel::query()->whereKey($parent->getId())->delete();
+        SetModel::query()->whereKey($set->getId())->delete();
+
+        $this->credentialedGet('/api/schedules/1')
+            ->assertOk()
+            ->assertExactJson($createdResponse->json());
+    }
+
     public function test_it_hides_another_users_schedule(): void
     {
         $owner = $this->createUser('owner@example.com');

backend/tests/Unit/Schedule/UseCases/CreateScheduleTest.php

@@ -107,16 +107,20 @@ class CreateScheduleTest extends TestCase
         ));
         $this->assertSame(
             [
-                $genesisChapterOne->getId(),
+                $genesisChapterOne->getName(),
-                $genesisChapterTwo->getId(),
+                $genesisChapterTwo->getName(),
-                $genesisChapterThree->getId(),
+                $genesisChapterThree->getName(),
-                $exodusChapterOne->getId(),
+                $exodusChapterOne->getName(),
-                $exodusChapterTwo->getId(),
+                $exodusChapterTwo->getName(),
             ],
-            array_map(function ($assignment): int {
+            array_map(function ($assignment): string {
-                return $assignment->getElement()->getId();
+                return $assignment->getName();
             }, $schedule->getAssignments()),
         );
+        $this->assertSame(
+            ['Genesis', 'Creation', 'Genesis 1'],
+            $schedule->getAssignments()[0]->getPath(),
+        );
         $this->assertSame(
             [
                 '2026-08-10',