code: protected void copyFile(File src, File dest, Replacement replaceFn) throws IOException {
          boolean isSource = isSourceFile(src);
          copyFile(src, dest, replaceFn, isSource);
      }
docs: Copies single file from <code>src</code> to <code>dest</code>.
  If the file is source file, variable references will be escaped, so they'll survive Velocity template merging.