Migrate mapper unit tests

tests/Unit/Mapper/ArrayMapperTest.php

@@ -0,0 +1,18 @@
+<?php
+/**
+ * @author Daniel J. Summers <daniel@bitbadger.solutions>
+ * @license MIT
+ */
+
+declare(strict_types=1);
+
+use BitBadger\PDODocument\Mapper\ArrayMapper;
+
+pest()->group('unit');
+
+describe('->map()', function () {
+    test('returns the given array', function () {
+        $result = ['one' => 2, 'three' => 4, 'eight' => 'five'];
+        expect((new ArrayMapper())->map($result))->toBe($result);
+    });
+});