Set PhpUnit version for older php

tests/BaseTestCase.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace Tests\FFMpeg;
+
+use PHPUnit\Framework\TestCase;
+
+class BaseTestCase extends TestCase
+{
+    public function assertScalar($value, $message = '')
+    {
+        $this->assertTrue(is_scalar($value), $message);
+    }
+
+    /**
+     * Can be removed when phpunit 4.8 (<= needed for php 5.5) support is removed.
+     */
+    public function assertIsArray($value, $message = '')
+    {
+        $this->assertTrue(is_array($value), $message);
+    }
+
+    /**
+     * Can be removed when phpunit 4.8 (<= needed for php 5.5) support is removed.
+     */
+    public function assertIsInt($value, $message = '')
+    {
+        $this->assertTrue(is_int($value), $message);
+    }
+
+    /**
+     * Can be removed when phpunit 4.8 (<= needed for php 5.5) support is removed.
+     */
+    public function assertIsBool($value, $message = '')
+    {
+        $this->assertTrue(is_bool($value), $message);
+    }
+
+    /**
+     * Can be removed when phpunit 4.8 (<= needed for php 5.5) support is removed.
+     */
+    public function assertIsString($value, $message = '')
+    {
+        $this->assertTrue(is_string($value), $message);
+    }
+
+    /**
+     * Can be removed when phpunit 4.8 (<= needed for php 5.5) support is removed.
+     */
+    public function expectException($exception)
+    {
+        // PHPUnt BC Layer
+        if (method_exists(get_parent_class(), 'expectException')) {
+            parent::expectException($exception);
+
+            return;
+        }
+
+        $this->setExpectedException($exception);
+    }
+}