Embracing. with. Noopur Gupta. Eclipse JDT co-lead. IBM

Transcription

1 Embracing Noopur Gupta Eclipse JDT co-lead IBM India 1

2 JUnit Framework JUnit 4.0 Released in 2006 JUnit 5.0 Released in September 2017 The top 20 Java libraries on GitHub in 2017 Source: 2

3 JUnit 4 developers IDEs developers Build tools developers Testing frameworks developers junit.jar (Single JUnit 4 JAR) (+ org.hamcrest.core.jar) Problems Modularity (single JAR) Developers accessing internals and duplicating code Maintainability Extensibility (via Runners and Rules) Java 8 support (Lambdas, Streams, Default Methods etc.) 3

4 JUnit 5 Architecture 5 th planet in Solar System! JUnit 5 = Platform + Jupiter + Vintage Source: 4

5 JUnit 5 Architecture JUnit Platform junit-platform-launcher Launcher APIs used by IDEs and build tools to launch the framework. Finds test engines via Java s ServiceLoader mechanism. junit-platform-engine TestEngine APIs for integration of any testing framework that runs on platform. JUnit Jupiter junit-jupiter-api APIs for the new programming and extension model. junit-jupiter-engine JupiterTestEngine - To discover and execute Jupiter tests. JUnit Vintage junit-vintage-engine To discover and execute JUnit 3 and JUnit 4 tests on JUnit 5 platform. 5

6 A sneak peek into the major interesting features of JUnit Jupiter with Eclipse support for JUnit 5. 6

7 Eclipse support for JUnit 5 Eclipse Oxygen.1a (4.7.1a) Eclipse Photon (4.8) M2 onwards Software site repository to update Eclipse Oxygen (4.7 and 4.7.1): Demo: Eclipse Photon (4.8) M2 milestone build 7

8 Demo JUnit Jupiter - Programming Model 8

9 Create a new JUnit Jupiter test Create a new JUnit Jupiter test in Eclipse with lifecycle method stubs for a class and its methods under test: New JUnit Test Case wizard -> New JUnit Jupiter test 9

10 Add JUnit 5 library to the build path New JUnit Test Case wizard offers to add it while creating a new JUnit Jupiter test. Add library (JUnit) in Java Build Path dialog. Quick Fix (Ctrl+1) proposal 10

11 Visibility Test classes and methods can have any access modifier (other than private). Annotations JUnit (No expected and @Disabled 11

12 Create a new JUnit Jupiter test method Create a JUnit Jupiter test method in Eclipse with the new template: test_jupiter 12

13 Assertions (org.junit.jupiter.api.assertions class) Failure message comes at the end of arguments list. Failure message can be retrieved lazily. Grouped assertions to execute all assertions first and then report all failures together. Exception testing to assert and evaluate a thrown exception. Asserting that the given task completes before the given timeout. 13

14 Assumptions (org.junit.jupiter.api.assumptions class) 14

15 Eclipse Favorites JUnit Jupiter s Assertions, Assumptions, DynamicContainer & DynamicTest classes are now added to Eclipse Favorites by default. Preferences -> Java -> Editor -> Content Assist -> Favorites Import static methods in your code from favorite classes via Content Assist (Ctrl + Space) and Quick Fix (Ctrl + 1). Configure the number of static member imports needed before type.* is used. 15

16 @DisplayName Provide custom display names for test classes and test methods - with spaces, special characters, and even emojis! Use Go to File action or just double-click to navigate to the test from JUnit view. 16

17 @Nested test classes Non-static nested classes (i.e. inner classes) can serve tests for logical grouping of test cases. Example: TestingAStackDemo in JUnit 5 user guide. (Re-)Run a test class by using the Run action in JUnit view or Outline view. You can even right-click on a nested test class name in the editor and use the Run As action. 17

18 Test interfaces and default methods Default test methods can be inherited by implementing test classes. Enables multiple inheritance in tests classes. Example: StringTests in JUnit 5 user guide. 18

19 Tagging and Filtering Tag test classes and test methods Tags can later be used to filter test execution. Provide tags to be included in or excluded from a test run via Configure Tags dialog in its JUnit launch configuration. 19

20 Meta-annotations and composed annotations JUnit Jupiter annotations can be used as meta-annotations. Create custom composed annotation inheriting semantics of its meta-annotations. 20

21 Dynamic Tests Dynamic tests are generated at runtime by method. Create method in Eclipse with the new template: test_factory Dynamic container is composed of a display name and a list of dynamic nodes. Dynamic test is composed of a display name and an Executable. There are no lifecycle callbacks for individual dynamic tests. 21

22 Navigate to failing source location Double-click an entry in JUnit view s failure trace to jump to the corresponding source location. Click "Show Stack Trace in Console View" button and use the hyperlinks. It can also be used to copy parts of the stack trace. 22

23 Dependency Injection Test constructors and methods are now permitted to have parameters enabling Dependency Injection. ParameterResolver is the extension API to provide a parameter resolver which dynamically resolves a parameter at runtime. A parameter resolver can be registered ) annotation. JUnit Jupiter provides some built-in resolvers which are registered automatically: o TestInfo (resolved by TestInfoParameterResolver) to access information about the currently executing test: 23

24 Dependency Injection o TestReporter (resolved by TestReporterParameterResolver) to publish additional data from the currently executing test which can be seen in the Console view in Eclipse: To support overloaded test methods, the Test Method Selection dialog in JUnit launch configuration now shows the method parameter types also: 24

25 Repeated Tests Repeat a test by annotating the method and specifying the number of repetitions. name attribute: to optionally specify a custom display name for each repetition. RepetitionInfo: as test method parameter to get information about the current repetition. 25

26 Parameterized Tests Run a test multiple times with different arguments by: annotating the method and declaring at least one source to provide the arguments. name attribute: to optionally specify a custom display name for each invocation. Test method may have additional parameters to be resolved by other ParameterResolvers at the end of the method's parameter list. 26

27 Test Instance Lifecycle By default, JUnit Jupiter creates a new instance of the test class before executing each test method. To execute all test methods on the same instance of the test class, you can annotate the test class The per-class mode makes it possible to annotations on: o Non-static methods o Interface default methods o Methods test classes 27

28 JUnit Jupiter - Extension Model Provides extension points as interfaces in org.junit.jupiter.api.extension package to be implemented by extension providers. Register one or more extensions declaratively on a test class, test method, or composed annotation ). JUnit Jupiter also supports global extension registration via Java s ServiceLoader mechanism. See the JUnit 5 User Guide for more details. 28

29 In summary Modular architecture Modern programming model Powerful extension model Gentle migration path Eclipse IDE support 29

30 References & Resources Eclipse support for JUnit 5 Download Photon (4.8) M2 & above: Download Oxygen.1a (4.7.1a): Software site to update Oxygen (4.7 & 4.7.1): Report bugs/enhancements: 30

31 References & Resources JUnit 5 Project User Guide Javadoc GitHub Gitter Q&A

32 32

33 33

34 Eclipse Converge 2017 Embracing JUnit 5 with Eclipse Noopur Gupta, IBM 34