How to achieve more granularity with running TestNG test cases? - java

At present, I have two types of execution choices in my project:
testSuite.xml: where I am able to include methods and classes of my choice to each suite
Added a runtime argument in maven goals in jenkins job. -Dsomeproperty=propetyValue: reading that through system properties as any VM arg, which is giving me choice inside the test methods to execute a certain condition. For example, if I do a transaction and the application allows negative balance in the account, then I can write the argument as -DallowNegativeBalance=true and read that inside the test method, when true, it will not fail the validation due to negative balance. Just an example.
Now I want to add more granularity to have more controls, for example,
Control the conditions within the test method.
Control the entire test method.
Control the entire test class.
Control the entire test suite.
And all this not inside program only, ideally one should be able to control that depending upon the user stage of deployment (means one stage can have a specific flow of deployment, for example, with allow negative balance true as above), so the CI FT job should be in such a way that above mentioned controls are possible. Like, within the testSuite also, some methods dont get executed, or even some classes which are not relevant to that negative balance flow are not executed. How can I achieve that?
I am a Java dev with little exp in TestNG limited to the suites and the maven arg mentioned in the beginning. Help is appreciated.

Related

JUnit - make sure that a function is invoked on every path

I know how to make sure that a function has been invoked, using:
mockito.verify
now, I want to make sure that on every path of the function (every 'if', 'if else' and 'else') - the function was invoked.
I can basically write unit test for every case, but I want to make sure that if any further cases will be added - there will also be invocation to that method.
Unit testing alone will not do that. You have to look into using coverage in order to get there.
Unit testing can only tell you if the paths that were taken resulted in a "valid" result; but there is no knowledge of "all paths" that exist; and if they were all hit.
So you want to turn here for example and learn which coverage tool would work for you.
When you are working with eclipse or intellij, those things work out of the box; you can install plugins like cobertura or eclemma within eclipse; and then do a "run unit test with coverage".
But of course: that only results in a number. You then have to look carefully at your code to understand if you are happy with that number (where those IDEs make that really easy; they can show you your source code, and which paths were taken).
Meaning: coverage is a whole concept, and you have to understand what that means; and in which way you can make that concept helpful for your daily work. For example, you the last thing you want is your boss giving you a specific target goal for coverage.
And just to be sure: there is no tooling that tells you: you added new code, and now this specific method invocation is no longer coming through all parts. What coverage gives you is that you had 75.32% coverage before your change; and afterwards, it went down to 74.01% ... the rest is then up to you.
now, I want to make sure that on every path of the function (every 'if', 'if else' and 'else') - the function was invoked.
You don't want that.
The misunderstanding is that you don't test "the code". You test public observable behavior. In your case the behavior is that your unit under test (UuT) (after doing other stuff) calls a method on a dependency (I hope).
You don't want to test "the code" because it may change for becoming cleaner and/or support more behavior. But then you don't want to change your existing tests since they will guarantee that the desired behavior is preserved during your refactoring.
On the other hand each test method should verify exactly one expectation about the UuTs behavior. This means that you should already have one test method for each execution path though your if/else cascade. So all you have to do is to add the verify() instruction to each of this test methods.
Finally you may have an easier job testing your code if you force Single Layer of Abstraction principle which basically says that a method either calls methods on some dependencies (aka "dispatching"), calls internal methods or does low level operations. This principle may lead to a design, where the "low level" stuff your UuT currently does moves to a new dependency so that your UuT only needs to do two calls on some dependencies in a certain order...
I have encountered this issue before where I needed to tightly test bound the switch cases, and I was desperate enough to do that.
I am asuming test coverage analysis is not enough for you. For me, the if-else conditions part was so critical that changing something unintentionally could have proved greatly disastrous, so I could not afford to leave a failure prone code and I needed a test case to satisfy myself.
How I satisfied myself is here:
1: Changed the conditions such as if..else, etc to a swich case variable - TaskSwitcherEnum, say taskSwitcher, and performed all sorts of operations under various possible values of TaskSwitcherEnum.
switch (taskSwitcher){
case TaskSwitcherEnum.Task_Type_1:
//do Something before break
break;
case TaskSwitcherEnum.Task_Type_2:
//do Something again
break;
...
}
2: Tightly tested the desired method for all possible values of taskSwitcherEnum. Mockito.verify(), whether required task method is called once, for each given TaskSwitcherEnum value.
3: Finally did a junit like this:
assertEquals("Task performance strategy is designed to handle only five cases.", 5, taskSwitcherEnum.values().length);
Doing this made sure [at least test covered] following things:
1: That my code has only desired branches, and any other code branch addition/deletion is caught by a test case.
2: That each branch does it's desired job by calling a method that I want, through testing on every particular Enum values against a called method.
Gist of the whole answer is, sometimes a little design change helps a lot.

TestNG - #BeforeMethod for specific methods

I'm using Spring Test with TestNG to test our DAOs, and I wanted to run a specific text fixture script before certain methods, allowing the modifications to be rolled back after every method so that the tests are free to do anything with the fixture data.
Initially I thought that 'groups' would be fit for it, but I already realized they're not intended for that (see this question: TestNG BeforeMethod with groups ).
Is there any way to configure a #BeforeMethod method to run only before specific #Tests? The only ways I see are workarounds:
Define an ordinary setup method and call at the beginning of every #Test method;
Move the #BeforeMethod method to a new class (top level or inner class), along with all methods that depend on it.
Neither is ideal, I'd like to keep my tests naturally grouped and clean, not split due to lack of alternatives.
You could add a parameter your #BeforeMethod with the type 'java.lang.reflect.Method'. TestNG will then inject the reflection information for the current test method including the method name, which you could use for switching.
If you add another 'Object' parameter, you will also get the invocation parameters of the test method.
You'all find all on possible parameters for TestNG-annotated methods in chapter 5.18.1 of the TestNG documentation.
Tests are simply not designed to do this. Technically speaking, a single tests is supposed to handle being idempotent for itself meaning it sets up, tests, and takes down. That is a single test. However, a lot of tests sometimes have the same set-up and take down method, whereas other tests need one set-up before they all run. This is the purpose of the #Before type tags.
If you don't like set-up and tear-down inside your test, your more then welcome to architect your own system, but technically speaking, if certain methods require specific set-ups or tear-downs, then that really should be embodied IN the test, since it is a requirement for test to pass. It is ok to call a set-up method, but ultimately, it should be OBVIOUS that a test needs a specific set-up in order to pass. After all, if your using specific set-ups, aren’t you actually testing states rather than code?

How to write automated tests - Test case as a function or test case as a class

I am having a design problem in test automation:-
Requirements - Need to test different servers (using unix console and not GUI) through automation framework. Tests which I'm going to run - Unit, System, Integration
Question: While designing a test case, I am thinking that a Test Case should be a part of a test suite (test suite is a class), just as we have in Python's pyunit framework. But, should we keep test cases as functions for a scalable automation framework or should be keep test cases as separate classes(each having their own setup, run and teardown methods) ? From automation perspective, Is the idea of having a test case as a class more scalable, maintainable or as a function?
Normally Test Cases are used as classes rather than functions because each test case has own setup data and initialization mechanism. Implementing test cases as a single function will not only make difficult to set up test data before running any test case, but yes you can have different test method in a test case class if you are running same test scenario.
The following is my opinion:
Pros of writing tests as functions:
If you need any pre-requisites for that test case, just call another function which provides the pre-requisites. Do the same thing for teardown steps
Looks simple for a new person in the team. Easy to undertstand what is happening by looking into tests as functions
Cons of writing tests as functions:
Not maintainable - Because if there are huge number of tests where
same kind of pre-requisites are required, the test case author has to
maintain calling each pre-requisite function in the test case. Same
for each teardown inside the test case
If there are so many calls to such a pre-requisite function inside many test cases, and if anything changes in the product functionality etc, you have to manually make efforts in many places again.
Pros of writing test cases as classes:
Setup, run and teardown are clearly defined. the test pre-requisites are easily understood
If there is Test 1 which is does something and the result of Test 1 is used as a setup pre-requisite in Test 2 and 3, its easy to just inherit from Test 1, and call its setup, run a teardown methods first, and then, continue your tests. This helps make the tests independent of each other. Here, you dont need to make efforts to maintain the actual calling of your code. It will be done implicitly because of inheritance.
Sometimes, if the setup method of Test 1 and run method of Test 2 might become the pre-requisites of another Test 3. In that case, just inherit from both of Test 1 and Test 2 classes and in the Test 3's setup method, call the setup of Test 1 and run of Test 2. Again you dont need to need to maintain the calling of the actual code, because you are calling the setup and run methods, which are tried and tested from the framework perspective.
Cons of writing test case as classes:
When the number of tests increase, you cant look into a particular test and say what it does, because it may have inherited so much levels that you cant back track. But, there is a solution around it - Write doc strings in each setup, run, teardown method of each test case. And, write a custom wrapper to generate doc strings for each test case. While/After inheriting, you should provide an option to add/Remove the docstring of a particular function (setup, run, teardown) to the inherited function. This way, you can just run that wrapper and get information about a test case from its doc-strings

Weird problem with doing tests with junit

I'm writing a little library for movies for myself. It's partly for learning TDD. Now I have a problem I can't solve.
The code is in here https://github.com/hasanen/MovieLibrary/blob/master/movielibrary-core/src/test/java/net/pieceofcode/movielibrary/service/MovieLibraryServiceITC.java
The problem is that when I run the whole class (right click above class name in eclipse), the second test fails because removing doesn't succeed. But when right clicking the method (getMovieGenres_getAllGenresAndRemoveOne_returnsTwoGenreAndIdsAreDifferent) and choosing Run as Junit Test, it works.
I don't necessarily need the fix, but at least some advice on how to find why junit is acting like this.
From the way you explain the problem, the problem appears to be in the setUp class. The setUp class runs before every test case invocation. This is the general sequence.
1- Add three movies.
2- Test if three movies exists.
3- Add three movies
4- remove movie item # 1.
Since sequence 1-4 works, the problem is sequence 3. Either sequence 3 swallows some exception or mutates the underlying object. (may be changes the sequence.) Without knowing how addMovie changes the underlying object, its hard to tell.
Something outside your test class (likely a superclass) is creating movieLibraryService, and it's not being recreated as often as it needs to be for independent testing.
If you add the line
movieLibraryService = new MovieLibraryService();
at the top of your testSetUp() method, this service will be properly reset before the running of each test method, and they will likely work properly.
As it is, I suspect you're getting a failure on the assertions about size, as the size is becoming 6 instead of 3.
Alternatively, you could add a teardown method (annotated with #After) which removes the contents of the movie library so that it always starts empty.
IMHO the problem is your test isn't real unit test but integration one. So while testing your service you're testing all the layers it uses. I recommend yo to use mocks for lower layers dependencies (EasyMock or something) and use integration tests only for your repository layer. This way you can avoid persistence layer influences while testing service layer.

JUnit dynamic method dispatch?

Here is the problem I am facing. I have been tasked with testing the query parsing engine of a piece of software through negative testing. That is, I must write a large number of queries that will fail, and test that they do indeed fail, as well as having the expected error message for the particular error in the query. These are defined in an XML file. I've written a simple wrapper around the parsing of the XML document and struct-like classes for these test cases.
Now, given that I am using JUnit as a testing framework, I'm running into this issue - the act of running through all of these externally defined tests lives in a single method. If a single test fails, then no more will be run. Is there any way to dynamically dispatch a method to handle each of the tests as I encounter them? This way, if a test fails, we can still run the remaining ones while getting a report on what did and did not fail.
The other alternative is, of course, writing all of the JUnit tests. I'd like to avoid this for many reasons, one of which is that the number of tests to be run is extremely large, and a test case is 99% boilerplate code.
Thanks.
You should look into JUnit's Parameterized annotation.
If I understand correctly, the input data and expected results are all defined in XML, so you don't need specific code to handle each test case?
If you use JUnit4, you could write your own Runner implementation. You could either implement Runner directly or extend ParentRunner. All you need to implement is one method that returns a description of the tests, and another method that runs the tests.

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