package com.example.util;

import org.junit.jupiter.api.Test;

import static org.junit.jupiter.api.Assertions.assertEquals;

class SubtractFunctionTest {

    private final SubtractFunction subtractFunction = new SubtractFunction();

    @Test
    void subtractsMultipleValues() {
        assertEquals(1.0, subtractFunction.calc(6.0, 2.0, 3.0));
    }

    @Test
    void returnsSingleValue() {
        assertEquals(5.0, subtractFunction.calc(5.0));
    }

    @Test
    void returnsZeroForNoInput() {
        assertEquals(0.0, subtractFunction.calc());
    }

    @Test
    void subtractsNegativeValues() {
        assertEquals(3.0, subtractFunction.calc(1.0, -2.0));
    }
}