UnitsConverterTest.java

packagecom.thealgorithms.conversions;

importstaticjava.util.Map.entry;
importstaticorg.junit.jupiter.api.Assertions.assertEquals;
importstaticorg.junit.jupiter.api.Assertions.assertThrows;

importjava.util.Map;
importjava.util.NoSuchElementException;
importjava.util.Set;
importorg.apache.commons.lang3.tuple.Pair;
importorg.junit.jupiter.api.Test;

publicclassUnitsConverterTest {

@Test
voidtestConvertThrowsForSameUnits() {
finalUnitsConvertersomeConverter = newUnitsConverter(Map.ofEntries(entry(Pair.of("A", "B"), newAffineConverter(10.0, -20.0))));
assertThrows(IllegalArgumentException.class, () -> someConverter.convert("A", "A", 20.0));
assertThrows(IllegalArgumentException.class, () -> someConverter.convert("B", "B", 20.0));
 }

@Test
voidtestConvertThrowsForUnknownUnits() {
finalUnitsConvertersomeConverter = newUnitsConverter(Map.ofEntries(entry(Pair.of("A", "B"), newAffineConverter(10.0, -20.0))));
assertThrows(NoSuchElementException.class, () -> someConverter.convert("A", "X", 20.0));
assertThrows(NoSuchElementException.class, () -> someConverter.convert("X", "A", 20.0));
assertThrows(NoSuchElementException.class, () -> someConverter.convert("X", "Y", 20.0));
 }

@Test
voidtestAvailableUnits() {
finalUnitsConvertersomeConverter = newUnitsConverter(Map.ofEntries(entry(Pair.of("Celsius", "Fahrenheit"), newAffineConverter(9.0 / 5.0, 32.0)), entry(Pair.of("Kelvin", "Celsius"), newAffineConverter(1.0, -273.15))));
assertEquals(Set.of("Celsius", "Fahrenheit", "Kelvin"), someConverter.availableUnits());
 }

@Test
voidtestInvertConversion() {
finalUnitsConvertersomeConverter = newUnitsConverter(Map.ofEntries(entry(Pair.of("A", "B"), newAffineConverter(2.0, 5.0))));
// Check conversion from A -> B
assertEquals(25.0, someConverter.convert("A", "B", 10.0), 0.0001);
// Check inverse conversion from B -> A
assertEquals(10.0, someConverter.convert("B", "A", 25.0), 0.0001);
 }
}