flutter_application_1/test/unit_test.dart

import 'package:flutter_test/flutter_test.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter_application_1/utils.dart';
import 'package:flutter_application_1/enums.dart';
import 'package:flutter_application_1/calculator.dart';

void main() {
  group('Calculation Tests', () {
    test('Calculates correct invested money', () {
      expect(calculateInvestedMoney(1000, 100, 5, []), equals(7000.0));
      expect(calculateInvestedMoney(2000, 50, 10, []), equals(8000.0));
    });
    test('Calculates correct compound interest', () {
      // Testen mit jährlicher Auszahlung
      List<double> investedMoneyListYearly = [];
      List<double> compoundInterestListYearly = [];
      calculateInvestedMoney(1000, 100, 10, investedMoneyListYearly);
      expect(calculateCompoundInterest(1000, 100, 5, 10, PayoutInterval.yearly, investedMoneyListYearly, compoundInterestListYearly), equals(16722.0));

      // Testen mit monatlicher Auszahlung
      List<double> investedMoneyListMonthly = [];
      List<double> compoundInterestListMonthly = [];
      calculateInvestedMoney(2000, 50, 10, investedMoneyListMonthly);
      expect(calculateCompoundInterest(2000, 50, 5, 10, PayoutInterval.monthly, investedMoneyListMonthly, compoundInterestListMonthly), equals(11058.0));
    });
    test('Calculates correct invested money with extremely high input values', () {
      expect(calculateInvestedMoney(1e15, 1e12, 100, []), equals(2.2e15));
    });
    test('Calculates correct invested money with extremely low input values', () {
      expect(calculateInvestedMoney(0, 0, 0, []), equals(0.0));
      expect(calculateInvestedMoney(0.1, 0.01, 0.001, []), equals(0.0));
    });
    test('Calculates correct compound interest with extremely high interest rate', () {
      List<double> investedMoneyListHighInterest = [];
      List<double> compoundInterestListHighInterest = [];
      calculateInvestedMoney(1000, 100, 10, investedMoneyListHighInterest);
      expect(calculateCompoundInterest(1000, 100, 1000, 10, PayoutInterval.yearly, investedMoneyListHighInterest, compoundInterestListHighInterest), equals(29049915553000.0));
    });
  });

  group('Utility Methods Tests', () {
    test('roundToInteger should round the value to the nearest integer', () {
      final controller = TextEditingController();
      controller.text = '2.7';
      roundToInteger(controller);
      expect(controller.text, '3');

      controller.text = '2.3';
      roundToInteger(controller);
      expect(controller.text, '2');
    });

    test('isNumeric should check if a string is a valid number', () {
      expect(isNumeric('123'), true);
      expect(isNumeric('12.3'), true);
      expect(isNumeric('12,3'), true);
      expect(isNumeric('abc'), false);
      expect(isNumeric('12a'), false);
    });

    test('restoreDefaultValuesIfEmpty should set default value 0 if the field is empty', () {
      final controller = TextEditingController();
      controller.text = '';
      restoreDefaultValuesIfEmpty(controller);
      expect(controller.text, '0');

      controller.text = '5';
      restoreDefaultValuesIfEmpty(controller);
      expect(controller.text, '5');
    });
  });
}