src/test/java/example/MainTest.java - master - Irelion/tdd

src/test/java/example/MainTest.java
117 строк4 KB
irelion
TDD-0005: add task 16
17 фев 2026, 15:22
17 фев 2026, 15:2264001b2
package example;

import org.junit.jupiter.api.Test;

import static example.Currency.DOLLAR;
import static example.Currency.FRANC;
import static org.junit.jupiter.api.Assertions.*;

class MainTest {

    private static Money ONE_DOLLAR = Money.dollar(1);
    private static Money ONE_FRANC= Money.franc(1);

    @Test
    void multiplicationTest() {
        final Money five = Money.dollar(5);
        assertEquals(Money.dollar(10), five.times(2));
        assertEquals(Money.dollar(15), five.times(3));
    }

    @Test
    void testEquality(){
        assertTrue(Money.dollar(5).equals(Money.dollar(5)));
        assertFalse(Money.franc(5).equals(Money.franc(6)));
        assertFalse(Money.dollar(5).equals(Money.franc(5)));
    }

    @Test
    void testCurrency() {
        assertEquals("USD", ONE_DOLLAR.currency());
        assertEquals("CHF", ONE_FRANC.currency());
    }

    @Test
    void testSimpleAddition() {
        final Money five = Money.dollar(5);
        final Expression plus  = five.plus(five);
        final Bank bank = new Bank();
        final Money reduced = bank.reduce(plus, DOLLAR.getCurrency());
        assertEquals(Money.dollar(10), reduced);

    }

    @Test
    void testPluReturnsSum() {
        final Money five = Money.dollar(5);
        final Expression result = five.plus(five);
        final Sum sum = ((Sum) result);
        assertEquals(five, sum.augend);
        assertEquals(five, sum.addend);
    }

    @Test
    void testReduceSum(){
        final Expression sum = new Sum(Money.dollar(3), Money.dollar(4));
        final Bank bank = new Bank();
        final Money result = bank.reduce(sum, DOLLAR.getCurrency());
        assertEquals(Money.dollar(7), result);
    }

    @Test
    void testReduceMoney(){
        final Bank bank = new Bank();
        final Money result = bank.reduce(ONE_DOLLAR, DOLLAR.getCurrency());
        assertEquals(ONE_DOLLAR, result);
    }

    @Test
    void testReduceMoneyDifferentCurrent() {
        final Bank bank = new Bank();
        bank.addRate(FRANC.getCurrency(), DOLLAR.getCurrency(), 2);
        final Money result = bank.reduce(Money.franc(2), DOLLAR.getCurrency());
        assertEquals(ONE_DOLLAR, result);

    }

    @Test
    void testIdentityRate(){
        assertEquals(1, new Bank().rate(DOLLAR.getCurrency(), DOLLAR.getCurrency()));
    }

    @Test
    void testMixedAdditions(){
        final Expression fiveBucks = Money.dollar(5);
        final Expression tenFrancs = Money.franc(10);
        final Bank bank = new Bank();
        bank.addRate(FRANC.getCurrency(), DOLLAR.getCurrency(), 2);
        final Money result = bank.reduce(fiveBucks.plus(tenFrancs), DOLLAR.getCurrency());

        assertEquals(Money.dollar(10), result);
    }

    @Test
    void testSumPlusMoney() {
        final Expression fiveBucks = Money.dollar(5);
        final Expression tenFrancs = Money.franc(10);
        final Bank bank = new Bank();

        bank.addRate(FRANC.getCurrency(), DOLLAR.getCurrency(), 2);
        final Expression sum = new Sum(fiveBucks, tenFrancs).plus(fiveBucks);
        final Money result = bank.reduce(sum, DOLLAR.getCurrency());

        assertEquals(Money.dollar(15), result);
    }

    @Test
    void testSumTimes(){
        final Expression fiveBucks = Money.dollar(5);
        final Expression tenFrancs = Money.franc(10);
        final Bank bank = new Bank();
        bank.addRate(FRANC.getCurrency(), DOLLAR.getCurrency(), 2);

        final Expression sum = new Sum(fiveBucks, tenFrancs).times(2);
        final Money result = bank.reduce(sum, DOLLAR.getCurrency());
        assertEquals(Money.dollar(20), result);
    }
}