private static boolean isOffsetInsideInjected(Editor injectedEditor, int injectedOffset) {
    if (injectedOffset == 0 || injectedOffset >= injectedEditor.getDocument().getTextLength()) {
      return false;
    }
    PsiFile injectedFile = ((EditorWindow)injectedEditor).getInjectedFile();
    InjectedLanguageManager ilm = InjectedLanguageManager.getInstance(injectedFile.getProject());
    TextRange rangeToEdit = new TextRange(injectedOffset - 1, injectedOffset+1);
    List<TextRange> editables = ilm.intersectWithAllEditableFragments(injectedFile, rangeToEdit);

    return editables.size() == 1 && editables.get(0).equals(rangeToEdit);
  }
private static boolean isOffsetInsideInjected(Editor injectedEditor, int injectedOffset)