@ValueSource for simple values in JUnit - Test Execution Trace

Test Overview

This test uses JUnit's @ValueSource to run the same test method multiple times with different simple input values. It verifies that the input strings are not empty.

Test Code - JUnit 5

JUnit

import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.ValueSource;
import static org.junit.jupiter.api.Assertions.assertFalse;

public class SimpleValueSourceTest {

    @ParameterizedTest
    @ValueSource(strings = {"apple", "banana", "cherry"})
    void testStringIsNotEmpty(String fruit) {
        assertFalse(fruit.isEmpty(), "String should not be empty");
    }
}

Execution Trace - 5 Steps

Step	Action	System State	Assertion	Result
1	Test runner starts and identifies the parameterized test method with @ValueSource	JUnit test environment ready to run tests	-	PASS
2	Test method 'testStringIsNotEmpty' runs with input 'apple'	Test method executing with parameter fruit='apple'	Check that 'apple'.isEmpty() is false	PASS
3	Test method 'testStringIsNotEmpty' runs with input 'banana'	Test method executing with parameter fruit='banana'	Check that 'banana'.isEmpty() is false	PASS
4	Test method 'testStringIsNotEmpty' runs with input 'cherry'	Test method executing with parameter fruit='cherry'	Check that 'cherry'.isEmpty() is false	PASS
5	All parameterized test runs complete	Test suite finished	All assertions passed for all inputs	PASS

Failure Scenario

Failing Condition: One of the input strings is empty, causing assertFalse(fruit.isEmpty()) to fail

Execution Trace Quiz - 3 Questions

What does the @ValueSource annotation do in this test?

A Defines the expected output values for the test

B Runs the test method multiple times with each provided input value

C Skips the test method for the given inputs

D Runs the test method only once with all inputs combined

Key Result

Using @ValueSource with parameterized tests helps run the same test logic with different inputs, improving test coverage and reducing code duplication.