@Nullable
  private static HighlightInfo.Builder checkGuardingExpressionHasBooleanType(@Nullable PsiExpression guardingExpression) {
    if (guardingExpression != null && !TypeConversionUtil.isBooleanType(guardingExpression.getType())) {
      String message = JavaErrorBundle.message("incompatible.types", JavaHighlightUtil.formatType(PsiTypes.booleanType()),
                                               JavaHighlightUtil.formatType(guardingExpression.getType()));
      return HighlightInfo.newHighlightInfo(HighlightInfoType.ERROR).range(guardingExpression).descriptionAndTooltip(message);
    }
    return null;
  }
@Nullable
  private static HighlightInfo.Builder checkGuardingExpressionHasBooleanType(@Nullable PsiExpression guardingExpression)