test: add function to make namespaces backwards compatible between di…

…fferent versions of PHPUnit

tests/Imgix/Tests/UrlBuilderTest.php

@@ -6,6 +6,17 @@
 
 class UrlBuilderTest extends \PHPUnit\Framework\TestCase {
 
+    private function testBackwardsCompatibility(){
+        // There is a difference in namespace structure 
+        // between different version of PHPUnit.
+        // This will perform any aliasing needed to support
+        // backwards compatibility.
+        if (!class_exists('\PHPUnit\Framework\TestCase') && class_exists('\PHPUnit_Framework_TestCase')) {
+            class_alias('\PHPUnit_Framework_TestCase', 'PHPUnit\Framework\TestCase');
+        }
+        assertTrue(true);
+    }
+
     public function testURLBuilderRaisesExceptionOnNoDomains() {
         // Because PHP treats warnings the same as exceptions,
         // they will be temporarily disabled in certain cases