anchor.diff:      Expect.equals(true, exceptionCaught);
       Expect.equals(true, !wrongExceptionCaught);
       file.closeSync();
  +    file.deleteSync();
       return 1;
     }
   
  
positive.code:     input.close();
      // Write the contents of the file just read into another file.
      String outFilenameBase = getFilename("tests/vm/data/fixed_length_file");
      file = new File(outFilenameBase + "_out");
      OutputStream output = file.openOutputStream();
      bool writeDone = output.writeFrom(buffer1, 0, 42);
      Expect.equals(true, writeDone);
      output.close();
      // Now read the contents of the file just written.
      List<int> buffer2 = new List<int>(42);
      file = new File(outFilenameBase + "_out");
      input = file.openInputStream();
      bytesRead = input.readInto(buffer2, 0, 42);
      input.close();
  
negative.code:                   file.closeHandler = () {
                      // Now read the contents of the file just written.
                      List<int> buffer2 = new List<int>(bytes_read);
                      file = new File(outFilename);
                      file.errorHandler = (s) {
                        Expect.fail("No errors expected");
                      };
  