diff -u b/core/scripts/run-tests.sh b/core/scripts/run-tests.sh
--- b/core/scripts/run-tests.sh
+++ b/core/scripts/run-tests.sh
@@ -312,7 +312,8 @@
       // This is the last line of defense.
       // @see simpletest_script_get_test_list()
       $test_class = array_shift($test_classes);
-      if (!method_exists($test_class, 'getInfo')) {
+      $class_info = new \ReflectionClass($test_class);
+      if (!$class_info->hasMethod('getInfo')) {
         continue;
       }
 
@@ -558,7 +559,8 @@
 
   // Filter out abstract/base classes.
   foreach ($test_list as $i => $test_class) {
-    if (!method_exists($test_class, 'getInfo')) {
+    $class_info = new \ReflectionClass($test_class);
+    if (!$class_info->hasMethod('getInfo')) {
       unset($test_list[$i]);
     }
   }