test pdf use case

backend/tests/Fakes/FakeStoredFileReader.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace Tests\Fakes;
+
+use App\Shared\Files\StoredFileReader;
+
+class FakeStoredFileReader implements StoredFileReader
+{
+    /**
+     * @var array<string, string>
+     */
+    private array $filesByPath = [];
+
+    /**
+     * @var string[]
+     */
+    public array $readPaths = [];
+
+    public function put(string $path, string $contents): void
+    {
+        $this->filesByPath[$path] = $contents;
+    }
+
+    public function read(string $path): ?string
+    {
+        $this->readPaths[] = $path;
+
+        return $this->filesByPath[$path] ?? null;
+    }
+}