Unit testing

IT1901 Fall 2020 - 10th Lecture

Testing

is an important part of software development
a way to ensure software quality
automated testing allows to develop new features with a minimal effort to check if the software still works as expected
testing frameworks

Testing (2)

design
implement
write automated tests
run tests
we do not test just for know, we write tests to keep running them during project life cycle

Testing (3)

design tests
implement the test
provide inputs
run the tests
provide expected outputs
check if the result we get matches what we expect
produce a manageable output that the developer can consult

Testing (3)

design tests
implement the test
provide inputs
run the tests
provide expected outputs
check if the result we get matches what we expect
produce a manageable output that the developer can consult

JUnit

Is a Java unit testing framework.
provides the means to automate test
allows to eliminate redundant testing tasks

JUnit 4

import org.junit.*;

public class FoobarTest {
    @BeforeClass
    public static void setUpClass() throws Exception {
        // Code executed before the first test method
    }

    @Before
    public void setUp() throws Exception {
        // Code executed before each test
    }

    @Test
    public void testOneThing() {
        // Code that tests one thing
    }

    @Test
    public void testAnotherThing() {
        // Code that tests another thing
    }

    @Test
    public void testSomethingElse() {
        // Code that tests something else
    }

    @After
    public void tearDown() throws Exception {
        // Code executed after each test
    }

    @AfterClass
    public static void tearDownClass() throws Exception {
        // Code executed after the last test method
    }
}

https://en.wikipedia.org/wiki/JUnit

JUnit 5

import org.junit.jupiter.api.*;

public class FoobarTest {
    @BeforeAll
    public static void setUpClass() throws Exception {
        // Code executed before the first test method
    }

    @BeforeEach
    public void setUp() throws Exception {
        // Code executed before each test
    }

    @Test
    public void testOneThing() {
        // Code that tests one thing
    }

    @Test
    public void testAnotherThing() {
        // Code that tests another thing
    }

    @Test
    public void testSomethingElse() {
        // Code that tests something else
    }

    @AfterEach
    public void tearDown() throws Exception {
        // Code executed after each test
    }

    @AfterAll
    public static void tearDownClass() throws Exception {
        // Code executed after the last test method
    }
}

JUnit 4 vs JUnit 5

Element	JUnit 4	JUnit 5
package	org.junit.*	org.junit.jupiter.api.*
code before first test	@BeforeClass	@BeforeAll
code before each test	@Before	@BeforeEach
test	@Test	@Test
code after each test	@After	@AfterEach
code after last test	@AfterClass	@AfterAll

Element

JUnit 4

JUnit 5

package

org.junit.*

org.junit.jupiter.api.*

code before first test

@BeforeClass

@BeforeAll

code before each test

@Before

@BeforeEach

test

@Test

code after each test

@After

@AfterEach

code after last test

@AfterClass

@AfterAll

JUnit 4 vs JUnit 5 (2)

Element JUnit 4 JUnit 5

Element	JUnit 4	JUnit 5
ignoring test	@Ignore	@Disabled
assertions statically accessed with	`Assert.assert`…	`Assertions.assert`…
assertion messsage position	in the beginning of argument list	in the end of argument list

ignoring test

@Ignore

@Disabled

assertions statically accessed with

Assert.assert…

Assertions.assert…

assertion messsage position

in the beginning of argument list

in the end of argument list

Testing in simpleexample1

Testing in todo-list example

Norwegian University of Science and Technology