add test - not yet working

tests/TestCase/Filter/CleanCssTest.php

@@ -0,0 +1,46 @@
+<?php
+/**
+ * MiniAsset
+ * Copyright (c) Mark Story (http://mark-story.com)
+ *
+ * Licensed under The MIT License
+ * For full copyright and license information, please see the LICENSE.txt
+ * Redistributions of files must retain the above copyright notice.
+ *
+ * @copyright Copyright (c) Mark Story (http://mark-story.com)
+ * @since     0.0.1
+ * @license   http://www.opensource.org/licenses/mit-license.php MIT License
+ */
+namespace MiniAsset\Test\TestCase\Filter;
+
+use MiniAsset\Filter\CleanCss;
+use PHPUnit\Framework\TestCase;
+
+class CleanCssTest extends TestCase
+{
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+        $this->_cssDir = APP . 'css' . DS;
+        $this->filter = new CleanCss();
+    }
+
+    public function testUnminified()
+    {
+        $content = file_get_contents($this->_cssDir . 'unminified.css');
+        $result = $this->filter->output($this->_cssDir . 'unminified.css', $content);
+
+        $expected = file_get_contents($this->_cssDir . 'minified.css');
+        $this->assertEquals(trim($expected), $result);
+    }
+
+    public function testAlreadyMinified()
+    {
+        $content = file_get_contents($this->_cssDir . 'minified.css');
+        $result = $this->filter->output($this->_cssDir . 'minified.css', $content);
+
+        $expected = file_get_contents($this->_cssDir . 'minified.css');
+        $this->assertEquals(trim($expected), $result);
+    }
+}