TaxAggregatorTest.java

package io.konik.validation;

import io.konik.zugferd.entity.Tax;
import io.konik.zugferd.entity.trade.TradeTax;
import io.konik.zugferd.unece.codes.TaxCategory;
import io.konik.zugferd.unece.codes.TaxCode;
import org.junit.Test;

import java.math.BigDecimal;

import static io.konik.validation.AmountCalculator.TaxAggregator;
import static org.assertj.core.api.Assertions.assertThat;

public class TaxAggregatorTest {

	private Tax vat19 = new TradeTax()
			.setPercentage(BigDecimal.valueOf(19))
			.setType(TaxCode.VAT)
			.setCategory(TaxCategory.C);

	private Tax vat23 = new TradeTax()
			.setPercentage(BigDecimal.valueOf(23))
			.setType(TaxCode.VAT)
			.setCategory(TaxCategory.C);

	@Test
	public void taxBasisForEmptyTaxAggregatorIsEqualToZero() {
		//given:
		TaxAggregator aggregator = new TaxAggregator();
		//when:
		BigDecimal value = aggregator.calculateTaxBasis();
		//then:
		assertThat(value).isEqualByComparingTo(BigDecimal.ZERO);
	}

	@Test
	public void taxTotalForEmptyTaxAggregatorIsEqualToZero() {
		//given:
		TaxAggregator aggregator = new TaxAggregator();
		//when:
		BigDecimal value = aggregator.calculateTaxTotal();
		//then:
		assertThat(value).isEqualByComparingTo(BigDecimal.ZERO);
	}

	@Test
	public void shouldCalculateTaxBasisFromAddedTaxAmounts() {
		//given:
		TaxAggregator aggregator = new TaxAggregator();
		aggregator.add(vat19, BigDecimal.valueOf(100));
		aggregator.add(vat19, BigDecimal.valueOf(54));
		aggregator.add(vat19, BigDecimal.valueOf(2.34));
		aggregator.add(vat23, BigDecimal.valueOf(50));
		aggregator.add(vat23, BigDecimal.valueOf(99.99));
		//when:
		BigDecimal taxBasis = aggregator.calculateTaxBasis();
		//then:
		assertThat(taxBasis).isEqualByComparingTo(BigDecimal.valueOf(306.33));
	}

	@Test
	public void shouldCalculateTaxTotalFromAddedTaxAmounts() {
		//given:
		TaxAggregator aggregator = new TaxAggregator();
		aggregator.add(vat19, BigDecimal.valueOf(100));
		aggregator.add(vat19, BigDecimal.valueOf(54));
		aggregator.add(vat19, BigDecimal.valueOf(2.34));
		aggregator.add(vat23, BigDecimal.valueOf(50));
		aggregator.add(vat23, BigDecimal.valueOf(99.99));
		//when:
		BigDecimal taxBasis = aggregator.calculateTaxTotal();
		//then:
		assertThat(taxBasis).isEqualByComparingTo(BigDecimal.valueOf(64.20));
	}
}