void assertReadAccessAllowed() {
    if (ApplicationManager.getApplication().isReadAccessAllowed()) return;
    FileElement fileElement = TreeUtil.getFileElement(this);
    PsiElement psi = fileElement == null ? null : fileElement.getCachedPsi();
    if (psi == null) return;
    FileViewProvider provider = psi instanceof PsiFile ? ((PsiFile)psi).getViewProvider() : null;
    boolean ok = provider != null && provider.getVirtualFile() instanceof ReadOnlyLightVirtualFile;
    if (!ok) {
      ApplicationManager.getApplication().assertReadAccessAllowed();
    }
  }
void assertReadAccessAllowed()