How to determine that a test has passed successfully after code changes?

A test is considered successful if, after making changes to the code, all assertions in the test method pass without errors or exceptions. In Java, this usually means that the test framework (e.g., JUnit) did not record any failures or errors during the test run.

Example with JUnit 5:

import static org.junit.jupiter.api.Assertions.*;
import org.junit.jupiter.api.Test;

class CalculatorTest {
    @Test
    void additionTest() {
        Calculator calc = new Calculator();
        assertEquals(5, calc.add(2, 3)); // if this assertion is true, the test passes
    }
}

If the add method returns 5 when adding 2 and 3, the test will pass successfully. If not, the test will fail, and this will be visible in the test report.