Method findFileIndex

arduino-core/src/processing/app/Sketch.java:225–233

Finds the file with the given filename and returns its index. Returns -1 when the file was not found.

(File filename)

   * Returns -1 when the file was not found.
   */
  public int findFileIndex(File filename) {
    int i = 0;
    for (SketchFile file : files) {
      if (file.getFile().equals(filename))
        return i;
      i++;
    }
    return -1;
  }

  /**
   * Check if renaming/saving this sketch to the given folder would