diff --git a/core/modules/migrate_drupal/src/Tests/MigrateCckFieldPluginManagerTest.php b/core/modules/migrate_drupal/src/Tests/MigrateCckFieldPluginManagerTest.php
index d403f51..723280d 100644
--- a/core/modules/migrate_drupal/src/Tests/MigrateCckFieldPluginManagerTest.php
+++ b/core/modules/migrate_drupal/src/Tests/MigrateCckFieldPluginManagerTest.php
@@ -41,12 +41,15 @@ public function testPluginSelection() {
 
     $this->assertIdentical('Drupal\\file\\Plugin\\migrate\\cckfield\\d7\\ImageField', get_class($plugin_manager->createInstance('image', ['core' => 7])));
     $this->assertIdentical('Drupal\\file\\Plugin\\migrate\\cckfield\\d7\\FileField', get_class($plugin_manager->createInstance('file', ['core' => 7])));
+
+    // Tests plugin selection when different plugins manage the same field_type
+    // in different versions of drupal.
     $this->assertIdentical('Drupal\\migrate_cckfield_plugin_manager_test\\Plugin\\migrate\\cckfield\\D6FileField', get_class($plugin_manager->createInstance('file', ['core' => 6])));
 
     $this->assertIdentical('Drupal\\text\\Plugin\\migrate\\cckfield\\TextField', get_class($plugin_manager->createInstance('text', ['core' => 6])));
     $this->assertIdentical('Drupal\\text\\Plugin\\migrate\\cckfield\\TextField', get_class($plugin_manager->createInstance('text', ['core' => 7])));
 
-    // Test fallback when no core version is specified.
+    // Tests fallback when no core version is specified.
     $this->assertIdentical('Drupal\\migrate_cckfield_plugin_manager_test\\Plugin\\migrate\\cckfield\\D6NoCoreVersionSpecified', get_class($plugin_manager->createInstance('d6_no_core_version_specified', ['core' => 6])));
 
     try {