private void checkOptionalDepthProblem(@NotNull PsiExpression expression, int optionalDepth, int pos) {
        if (optionalDepth < 0) {
          holder.registerProblem(expression, ExpressionUtils.findStringLiteralRange(expression, pos, pos + 1),
                                 InspectionGadgetsBundle.message("inspection.incorrect.date.format.message.unpaired", '['));
        }
      }
private void checkOptionalDepthProblem(@NotNull PsiExpression expression, int optionalDepth, int pos)