24-Testing

Question 1

From what Spring version JUnit 5 becomes the default JUnit version?

Answer 1

Spring Boot 2.2

Question 2

Components in JUnit 5

Answer 2

Platform
Jupiter: extension model & extensions
Vintage: support JUnit 3, 4

Question 3

What is the big difference between JUnit 4 and 5? Give an example

Answer 3

The big difference between 4 and 5 is the extension framework. Allows multiple frameworks to customize tests at the same time. For example to run Spring-based tests and use the test support of a mocking library too.

Question 4

New annotations in JUnit 5

Answer 4

@DisplayName - Displays the name of each test on the console when it is run
@Nested - Multiple nested tests can be defined in a single test
@ParameterizedTest - Run the same test multiple times with different arguments

Question 5

How to ignore a test in JUnit 5?

Answer 5

@Disabled

Question 6

What is @ContextConfiguration used for?

Answer 6

configration for TestContext

Question 7

Jar file of spring test framework

Answer 7

spring-test.jar

Question 8

What framework defines application context for Spring tests?

Answer 8

TestContext framework

Question 9

How to define a test class with SpringExtension?

Answer 9

@ExtendWith(SpringExtension.class) // mandatory
@ContextConfiguration(classes={SystemTestConfig.class}) // mandatory
public class TransferServiceTests {}

Note: shortcut @SpringJUnitConfig(SystemTestConfig.class)

Question 10

In which env does the following definition works?
void hello(@Autowired TransferService ts) {}

Answer 10

Only in test we can use @Autowired for argument

Question 11

What happens if using @SpringJUnitConfig without configuration class?

Answer 11

Spring will search static @Configuration embedded in test class

Question 12

About @TestPropertySource

Answer 12

Custom properties just for testing
Has higher precedence than sources
example:
@SpringJUnitConfig(SystemTestConfig.class)
@TestPropertySource(properties = { “username=foo”, “password=bar” },
locations = “classpath:/transfer-test.properties”)

Question 13

Write a Spring test with JUnit4

Answer 13

@RunWith(SpringRunner.class)
@ContextConfiguration(SystemTestConfig.class)
public class TransferServiceTests {}

Note: can use either SpringRunner or SpringJUnit4ClassRunner