Multiple parameter types in JUnit - Test Execution Trace

Test Overview

This test verifies a method that accepts multiple parameter types using JUnit's parameterized test feature. It checks that the method correctly processes different combinations of input values.

Test Code - JUnit 5

JUnit

import static org.junit.jupiter.api.Assertions.assertEquals;
import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.CsvSource;

public class CalculatorTest {

    public static int add(int a, int b) {
        return a + b;
    }

    @ParameterizedTest
    @CsvSource({
        "1, 2, 3",
        "-1, 1, 0",
        "100, 200, 300",
        "0, 0, 0"
    })
    void testAddMultipleParameters(int a, int b, int expected) {
        assertEquals(expected, add(a, b));
    }
}

Execution Trace - 6 Steps

Step	Action	System State	Assertion	Result
1	Test starts	JUnit test runner initializes CalculatorTest class	-	PASS
2	Runs parameterized test with parameters (1, 2, 3)	Method add(1, 2) is called	Check if add(1, 2) == 3	PASS
3	Runs parameterized test with parameters (-1, 1, 0)	Method add(-1, 1) is called	Check if add(-1, 1) == 0	PASS
4	Runs parameterized test with parameters (100, 200, 300)	Method add(100, 200) is called	Check if add(100, 200) == 300	PASS
5	Runs parameterized test with parameters (0, 0, 0)	Method add(0, 0) is called	Check if add(0, 0) == 0	PASS
6	All parameterized tests completed	Test suite finished with all assertions passed	-	PASS

Failure Scenario

Failing Condition: The add method returns incorrect sum for any parameter set

Execution Trace Quiz - 3 Questions

What does the @CsvSource annotation provide in this test?

A Multiple sets of parameters for the test method

B A single parameter value for the test

C The expected output only

D The test method name

Key Result

Using parameterized tests with multiple parameter types helps efficiently verify method behavior with various inputs, reducing repetitive code and improving test coverage.