Make sure transformers can be mocked.

app/Transformers/TransactionLinkTransformer.php

@@ -0,0 +1,88 @@
+<?php
+/**
+ * JournalLinkTransformer.php
+ * Copyright (c) 2018 thegrumpydictator@gmail.com
+ *
+ * This file is part of Firefly III.
+ *
+ * Firefly III is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Firefly III is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Firefly III. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Transformers;
+
+
+use FireflyIII\Models\Note;
+use FireflyIII\Models\TransactionJournalLink;
+use League\Fractal\TransformerAbstract;
+use Log;
+use Symfony\Component\HttpFoundation\ParameterBag;
+
+/**
+ *
+ * Class JournalLinkTransformer
+ */
+class JournalLinkTransformer extends TransformerAbstract
+{
+    /** @var ParameterBag */
+    protected $parameters;
+
+    /**
+     * CurrencyTransformer constructor.
+     *
+     * @codeCoverageIgnore
+     *
+     * @param ParameterBag $parameters
+     */
+    public function __construct(ParameterBag $parameters)
+    {
+        $this->parameters = $parameters;
+        if ('testing' === config('app.env')) {
+            Log::warning(sprintf('%s should not be instantiated in the TEST environment!', \get_class($this)));
+        }
+    }
+
+    /**
+     * @param TransactionJournalLink $link
+     *
+     * @return array
+     */
+    public function transform(TransactionJournalLink $link): array
+    {
+        $notes = null;
+        /** @var Note $note */
+        $note = $link->notes()->first();
+        if (null !== $note) {
+            $notes = $note->text;
+        }
+
+        $data = [
+            'id'         => (int)$link->id,
+            'created_at' => $link->created_at->toAtomString(),
+            'updated_at' => $link->updated_at->toAtomString(),
+            'inward_id'  => $link->source_id,
+            'outward_id' => $link->destination_id,
+            'notes'      => $notes,
+            'links'      => [
+                [
+                    'rel' => 'self',
+                    'uri' => '/transaction_links/' . $link->id,
+                ],
+            ],
+        ];
+
+        return $data;
+    }
+}