Index: tests/phpunit/tests/image/functions.php
===================================================================
--- tests/phpunit/tests/image/functions.php	(revision 26308)
+++ tests/phpunit/tests/image/functions.php	(working copy)
@@ -30,8 +30,10 @@
 		if ( extension_loaded( 'fileinfo' ) ) {
 			$finfo = new finfo();
 			$mime_type = $finfo->file( $filename, FILEINFO_MIME );
-		} elseif ( function_exists('mime_content_type') ) {
+		} elseif ( function_exists( 'mime_content_type' ) ) {
 			$mime_type = mime_content_type( $filename );
+		} else {
+			$this->markTestSkipped( 'The fileinfo PHP extension is not loaded.' );
 		}
 		if ( false !== strpos( $mime_type, ';' ) ) {
 			list( $mime_type, $charset ) = explode( ';', $mime_type, 2 );