anchor.diff:      }
       directory = directory.parent;
     }
  +  
  +  _DEVTOOLS_HOME = directory;
  +  
     return directory;
   }
   
   bool fileExists(String path) => new File(path).existsSync();
  +
  +File firstExistingFile(List<File> files) {
  +  for (var file in files) {
  +    if (file.existsSync()) {
  +      return file;
  +    }
  +  }
  +  return null;
  +}
positive.code: }
  
  Directory findDevToolsHome() {
    var directory = new File.fromUri(Platform.script).parent;
    while (!new File("${directory.path}/pubspec.yaml").existsSync()) {
      if (directory == null) {
  
negative.code: part of devtools.util;
  
  Directory _DEVTOOLS_HOME;
  
  File file(String path, [Directory directory]) {
    var it = "";
  