AC-953: Create unit test for Magento2\Less\TypeSelectorConcatenationSniff check

Author: loginesta

Magento2/Tests/Less/TypeSelectorConcatenationUnitTest.less

@@ -0,0 +1,25 @@
+// /**
+//  * Copyright © Magento, Inc. All rights reserved.
+//  * See COPYING.txt for license details.
+//  */
+
+.product-list-item {
+    background: green;
+}
+
+.product-image {
+    background: green;
+}
+
+.product {
+    random: 'stuff  ';
+    &-list {
+        background: red;
+        &-item {
+            background: red;
+        }
+    }
+    &-image {
+        background: red;
+    }
+}

Magento2/Tests/Less/TypeSelectorConcatenationUnitTest.php

@@ -0,0 +1,28 @@
+<?php
+/**
+ * Copyright © Magento. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento2\Tests\Less;
+
+class TypeSelectorConcatenationUnitTest extends AbstractLessSniffUnitTestCase
+{
+    /**
+     * @inheritdoc
+     */
+    public function getErrorList()
+    {
+        return [
+            16 => 1,
+            22 => 1
+        ];
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getWarningList()
+    {
+        return [];
+    }
+}