anchor.diff:          .createTempSync('flutter_test_compiler.');
       final File outputDill = outputDillDirectory.childFile('output.dill');
   
  +    printTrace('Compiler will use the following file as its incremental dill file: ${outputDill.path}');
  +
       bool suppressOutput = false;
       void reportCompilerMessage(String message) {
         if (suppressOutput)
  
positive.code:         while (compilationQueue.isNotEmpty) {
            final _CompilationRequest request = compilationQueue.first;
            printTrace('Compiling ${request.path}');
            compiler ??= createCompiler();
            suppressOutput = false;
            final CompilerOutput compilerOutput = await handleTimeout<CompilerOutput>(
  
negative.code:     return handleTimeout<String>(completer.future, mainDart);
    }
  
    Future<void> _shutdown() async {
      // Check for null in case this instance is shut down before the
      // lazily-created compiler has been created.
      if (compiler != null) {
        await compiler.shutdown();
        compiler = null;
      }
    }
  
    Future<void> dispose() async {
      await _shutdown();
      await compilerController.close();
    }
  
    static Future<T> handleTimeout<T>(Future<T> value, String path) {
  