DisplayCachedMessagesTest: allow for the tests to pass in CBF mode

Author: jrfnl

tests/Core/Ruleset/DisplayCachedMessagesTest.php

@@ -229,18 +229,24 @@ public function testNonBlockingErrorsDoNotShowUnderSpecificCircumstances($config
      */
     public static function dataSelectiveDisplayOfMessages()
     {
-        return [
-            'Explain mode'               => [
+        $data = [
+            'Explain mode' => [
                 'configArgs' => ['-e'],
             ],
-            'Quiet mode'                 => [
+            'Quiet mode'   => [
                 'configArgs' => ['-q'],
             ],
-            'Documentation is requested' => [
-                'configArgs' => ['--generator=text'],
-            ],
         ];
 
+        // Setting the `--generator` arg is only supported when running `phpcs`.
+        if (PHP_CODESNIFFER_CBF === false) {
+            $data['Documentation is requested'] = [
+                'configArgs' => ['--generator=text'],
+            ];
+        }
+
+        return $data;
+
     }//end dataSelectiveDisplayOfMessages()