test sets list endpoint

backend/tests/Fakes/FakeSetRepository.php

@@ -0,0 +1,49 @@
+<?php
+
+namespace Tests\Fakes;
+
+use App\Set\CreateSetDto;
+use App\Set\Set;
+use App\Set\SetRepository;
+
+class FakeSetRepository implements SetRepository
+{
+    /**
+     * @var array<int, Set>
+     */
+    private array $sets = [];
+
+    public function create(CreateSetDto $dto): Set
+    {
+        $id = count($this->sets) + 1;
+        $set = new Set(
+            id: $id,
+            name: $dto->name,
+            creator: $dto->creator,
+        );
+        $this->sets[$id] = $set;
+
+        return $this->copy($set);
+    }
+
+    public function all(): array
+    {
+        $sets = array_values($this->sets);
+        usort($sets, function (Set $first, Set $second): int {
+            return $first->getName() <=> $second->getName();
+        });
+
+        return array_map(function (Set $set): Set {
+            return $this->copy($set);
+        }, $sets);
+    }
+
+    private function copy(Set $set): Set
+    {
+        return new Set(
+            id: $set->getId(),
+            name: $set->getName(),
+            creator: $set->getCreator(),
+        );
+    }
+}