Making Symfony2 unit tests more DRY by extending WebTestCase - unit-testing

A lot of my tests have a lot of the same setUp()/tearDown() stuff going on. It seems dumb to copy and paste the same code into every single one of my unit tests. I think I want to create a new test class that extends WebTestCase that my other tests can extend.
My problem is that I don't really know how. First of all, where's the most appropriate place to put this new class? I tried making one just inside my Tests folder, but then none of my tests could actually find the class. Maybe I just don't understand namespaces.
Has anyone extended WebTestCase before in the way I'm talking about? If so, how did you do it?

I haven't done this, but I'd probably just do it like so
src/Your/Bundle/Test/WebTestCase.php
<?php
namespace Your\Bundle\Test
use Symfony\Bundle\FrameworkBundle\Test\WebTestCase as WTC;
class WebTestCase extends WTC
{
// Your implementation of WebTestCase
}

In my tests I usually extend the WebTestCase the way Peter proposed it. Additionally I use require_once to make the AppKernel available in my WebTestCase:
<?php
namespace My\Bundle\Tests;
use Symfony\Bundle\FrameworkBundle\Test\WebTestCase as BaseWebTestCase;
require_once(__DIR__ . "/../../../../app/AppKernel.php");
class WebTestCase extends BaseWebTestCase
{
protected $_application;
protected $_container;
public function setUp()
{
$kernel = new \AppKernel("test", true);
$kernel->boot();
$this->_application = new \Symfony\Bundle\FrameworkBundle\Console\Application($kernel);
$this->_application->setAutoExit(false);
...
My tests then look like this:
<?php
namespace My\Bundle\Tests\Controller;
use My\Bundle\Tests\WebTestCase;
class DefaultControllerTest extends WebTestCase
{
public function testIndex()
{
...

You don't need to extend WebTestCase to include AppKernel. You can use the following approach
$client = static::createClient();
self::$application = new Application($client->getKernel());

This question is really old but it ranks quite highly on Google, so I thought I'd add my solution.
I extended WebTestCase with a default setUp method and a logIn method so I could more easily run authenticated tests.
It seems you can't add standard classes to the tests directory because the unit tests won't find them. I'm not sure why. My solution was to add a directory src/_TestHelpers and put my helper classes in there.
So I have:
# src/_TestHelpers/ExtendedWTC.php
namespace _TestHelpers;
use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
class ExtendedWTC extends WebTestCase
{
# Do your cool extending here
}
and
# tests/AppBundle/Controller/DefaultControllerTest.php
namespace Tests\AppBundle;
use _TestHelpers\ExtendedWTC
class DefaultControllerTest extends ExtendedWTC
{
# Your tests here, using your cool extensions.
}
Note: I'm using the Symfony 3 directory structure, hence why my tests are in tests/ and not src/AppBundle/Tests/.
I hope this helps someone...

Related

Thymeleaf: Do not render during unit test?

As I haven't gotten an answer for my other question here, I am looking for another approach. Is there a way to no not execute or include a fragment during unit testing?
I want to display the version and build number in the footer of my templates, thus I have the following line:
<div class="versionInfo">Version <span th:text="${#buildProperties.getVersion()}"></span></div>
This works well when running the application, but during unit test I get the exception:
No bean named 'buildProperties' available
In the other question I am looking for a way to get this bean during unit test, as an alternative I am now looking for a way to exclude this template during unit tests. Something like this:
<div class="versionInfo" th:if="${!isUnitTest}">Version <span th:text="${#buildProperties.getVersion()}"></span></div>
I am using the following annotations on my test class:
#RunWith(SpringRunner.class)
#WebMvcTest(SimpleController.class)
If it's a standard unit-test, use Mockito to mock the bean:
#RunWith(MockitoJUnitRunner.class)
public class SomeTest{
#Mock
private BuildProperties buildProperties;
...
Or, if it's a Spring MVC test:
#RunWith(SpringRunner.class)
#WebMvcTest(value = MyController.class)
public class MyControllerTest{
#MockBean
private BuildProperties buildProperties;
The version will be null, because all of the methods of the mocked bean returns null.
if you want to emulate a real version you can add something like this to your test or to the setUp() method
given(buildProperties.getVersion()).willReturn("whatever");
--------------- edit
Unfortunately all of the above solutions work only if the buildProperties bean was added to the model directly.
But in your case you use the bean directly as a SpEL bean reference. Unfortunately I don't know any way to check if a bean exists in the context via SpEL.
Also, it's not a good practice to add extra code into your code for checking if it's running in test mode.
So I think the best solution if you create a nested test configuration class and define a default BuildProperties bean there.
#TestConfiguration
public static class TestConfig {
#Bean
BuildProperties buildProperties() {
return new BuildProperties(new Properties());
}
}
Or you can use #Import(TestConfig.class) if you need this extra configuration in multiple test classes.
I got a hint from a colleague that works for this question.
Just add an application.properties to src/test/resources with a custom property:
isUnitTest=true
Then I can simply check for this in my thymeleaf template:
<div class="versionInfo" th:if="${#environment.getProperty('isUnitTest') != 'true'}">Version <span th:text="${#buildProperties.getVersion()}"></span></div>
Though if someone finds a way to achieve this automatically with a thymeleaf setting or property I didn't find so far, I will accept it as an answer.

Mockito cannot mock/spy because final class [duplicate]

I have a final class, something like this:
public final class RainOnTrees{
public void startRain(){
// some code here
}
}
I am using this class in some other class like this:
public class Seasons{
RainOnTrees rain = new RainOnTrees();
public void findSeasonAndRain(){
rain.startRain();
}
}
and in my JUnit test class for Seasons.java I want to mock the RainOnTrees class. How can I do this with Mockito?
Mocking final/static classes/methods is possible with Mockito v2 only.
add this in your gradle file:
testImplementation 'org.mockito:mockito-inline:2.13.0'
This is not possible with Mockito v1, from the Mockito FAQ:
What are the limitations of Mockito
Needs java 1.5+
Cannot mock final classes
...
Mockito 2 now supports final classes and methods!
But for now that's an "incubating" feature. It requires some steps to activate it which are described in What's New in Mockito 2:
Mocking of final classes and methods is an incubating, opt-in feature. It uses a combination of Java agent instrumentation and subclassing in order to enable mockability of these types. As this works differently to our current mechanism and this one has different limitations and as we want to gather experience and user feedback, this feature had to be explicitly activated to be available ; it can be done via the mockito extension mechanism by creating the file src/test/resources/mockito-extensions/org.mockito.plugins.MockMaker containing a single line:
mock-maker-inline
After you created this file, Mockito will automatically use this new engine and one can do :
final class FinalClass {
final String finalMethod() { return "something"; }
}
FinalClass concrete = new FinalClass();
FinalClass mock = mock(FinalClass.class);
given(mock.finalMethod()).willReturn("not anymore");
assertThat(mock.finalMethod()).isNotEqualTo(concrete.finalMethod());
In subsequent milestones, the team will bring a programmatic way of using this feature. We will identify and provide support for all unmockable scenarios. Stay tuned and please let us know what you think of this feature!
add this in your build file:
if using gradle: build.gradle
testImplementation 'org.mockito:mockito-inline:2.13.0'
if using maven: pom.xml
<dependency>
<groupId>org.mockito</groupId>
<artifactId>mockito-inline</artifactId>
<version>2.13.0</version>
<scope>test</scope>
</dependency>
this is a configuration to make mockito work with final classes
If you faced the Could not initialize inline Byte Buddy mock maker. (This mock maker is not supported on Android.)
Add the Byte Buddy dependency to your build.gradle file:
testImplementation 'net.bytebuddy:byte-buddy-agent:1.10.19'
src: https://mvnrepository.com/artifact/net.bytebuddy/byte-buddy
You cannot mock a final class with Mockito, as you can't do it by yourself.
What I do, is to create a non-final class to wrap the final class and use as delegate. An example of this is TwitterFactory class, and this is my mockable class:
public class TwitterFactory {
private final twitter4j.TwitterFactory factory;
public TwitterFactory() {
factory = new twitter4j.TwitterFactory();
}
public Twitter getInstance(User user) {
return factory.getInstance(accessToken(user));
}
private AccessToken accessToken(User user) {
return new AccessToken(user.getAccessToken(), user.getAccessTokenSecret());
}
public Twitter getInstance() {
return factory.getInstance();
}
}
The disadvantage is that there is a lot of boilerplate code; the advantage is that you can add some methods that may relate to your application business (like the getInstance that is taking a user instead of an accessToken, in the above case).
In your case I would create a non-final RainOnTrees class that delegate to the final class. Or, if you can make it non-final, it would be better.
In Mockito 3 and more I have the same problem and fixed it as from this link
Mock Final Classes and Methods with Mockito
as follow
Before Mockito can be used for mocking final classes and methods, it needs to be > configured.
We need to add a text file to the project's src/test/resources/mockito-extensions directory named org.mockito.plugins.MockMaker and add a single line of text:
mock-maker-inline
Mockito checks the extensions directory for configuration files when it is loaded. This file enables the mocking of final methods and classes.
Use Powermock. This link shows, how to do it: https://github.com/jayway/powermock/wiki/MockFinal
Just to follow up. Please add this line to your gradle file:
testCompile group: 'org.mockito', name: 'mockito-inline', version: '2.8.9'
I have tried various version of mockito-core and mockito-all. Neither of them work.
I had the same problem. Since the class I was trying to mock was a simple class, I simply created an instance of it and returned that.
I guess you made it final because you want to prevent other classes from extending RainOnTrees. As Effective Java suggests (item 15), there's another way to keep a class close for extension without making it final:
Remove the final keyword;
Make its constructor private. No class will be able to extend it because it won't be able to call the super constructor;
Create a static factory method to instantiate your class.
// No more final keyword here.
public class RainOnTrees {
public static RainOnTrees newInstance() {
return new RainOnTrees();
}
private RainOnTrees() {
// Private constructor.
}
public void startRain() {
// some code here
}
}
By using this strategy, you'll be able to use Mockito and keep your class closed for extension with little boilerplate code.
Another workaround, which may apply in some cases, is to create an interface that is implemented by that final class, change the code to use the interface instead of the concrete class and then mock the interface. This lets you separate the contract (interface) from the implementation (final class). Of course, if what you want is really to bind to the final class, this will not apply.
Time saver for people who are facing the same issue (Mockito + Final Class) on Android + Kotlin. As in Kotlin classes are final by default. I found a solution in one of Google Android samples with Architecture component. Solution picked from here : https://github.com/googlesamples/android-architecture-components/blob/master/GithubBrowserSample
Create following annotations :
/**
* This annotation allows us to open some classes for mocking purposes while they are final in
* release builds.
*/
#Target(AnnotationTarget.ANNOTATION_CLASS)
annotation class OpenClass
/**
* Annotate a class with [OpenForTesting] if you want it to be extendable in debug builds.
*/
#OpenClass
#Target(AnnotationTarget.CLASS)
annotation class OpenForTesting
Modify your gradle file. Take example from here : https://github.com/googlesamples/android-architecture-components/blob/master/GithubBrowserSample/app/build.gradle
apply plugin: 'kotlin-allopen'
allOpen {
// allows mocking for classes w/o directly opening them for release builds
annotation 'com.android.example.github.testing.OpenClass'
}
Now you can annotate any class to make it open for testing :
#OpenForTesting
class RepoRepository
Actually there is one way, which I use for spying. It would work for you only if two preconditions are satisfied:
You use some kind of DI to inject an instance of final class
Final class implements an interface
Please recall Item 16 from Effective Java. You may create a wrapper (not final) and forward all call to the instance of final class:
public final class RainOnTrees implement IRainOnTrees {
#Override public void startRain() { // some code here }
}
public class RainOnTreesWrapper implement IRainOnTrees {
private IRainOnTrees delegate;
public RainOnTreesWrapper(IRainOnTrees delegate) {this.delegate = delegate;}
#Override public void startRain() { delegate.startRain(); }
}
Now not only can you mock your final class but also spy on it:
public class Seasons{
RainOnTrees rain;
public Seasons(IRainOnTrees rain) { this.rain = rain; };
public void findSeasonAndRain(){
rain.startRain();
}
}
IRainOnTrees rain = spy(new RainOnTreesWrapper(new RainOnTrees()) // or mock(IRainOnTrees.class)
doNothing().when(rain).startRain();
new Seasons(rain).findSeasonAndRain();
Give this a try:
Mockito.mock(SomeMockableType.class,AdditionalAnswers.delegatesTo(someInstanceThatIsNotMockableOrSpyable));
It worked for me. "SomeMockableType.class" is the parent class of what you want to mock or spy, and someInstanceThatIsNotMockableOrSpyable is the actual class that you want to mock or spy.
For more details have a look here
This can be done if you are using Mockito2, with the new incubating feature which supports mocking of final classes & methods.
Key points to note:
1. Create a simple file with the name “org.mockito.plugins.MockMaker” and place it in a folder named “mockito-extensions”. This folder should be made available on the classpath.
2. The content of the file created above should be a single line as given below:
mock-maker-inline
The above two steps are required in order to activate the mockito extension mechanism and use this opt-in feature.
Sample classes are as follows:-
FinalClass.java
public final class FinalClass {
public final String hello(){
System.out.println("Final class says Hello!!!");
return "0";
}
}
Foo.java
public class Foo {
public String executeFinal(FinalClass finalClass){
return finalClass.hello();
}
}
FooTest.java
public class FooTest {
#Test
public void testFinalClass(){
// Instantiate the class under test.
Foo foo = new Foo();
// Instantiate the external dependency
FinalClass realFinalClass = new FinalClass();
// Create mock object for the final class.
FinalClass mockedFinalClass = mock(FinalClass.class);
// Provide stub for mocked object.
when(mockedFinalClass.hello()).thenReturn("1");
// assert
assertEquals("0", foo.executeFinal(realFinalClass));
assertEquals("1", foo.executeFinal(mockedFinalClass));
}
}
Hope it helps.
Complete article present here mocking-the-unmockable.
Yes same problem here, we cannot mock a final class with Mockito. To be accurate, Mockito cannot mock/spy following:
final classes
anonymous classes
primitive types
But using a wrapper class seems to me a big price to pay, so get PowerMockito instead.
I think you need think more in principle. Instead you final class use his interface and mock interface instead.
For this:
public class RainOnTrees{
fun startRain():Observable<Boolean>{
// some code here
}
}
add
interface iRainOnTrees{
public void startRain():Observable<Boolean>
}
and mock you interface:
#Before
fun setUp() {
rainService= Mockito.mock(iRainOnTrees::class.java)
`when`(rainService.startRain()).thenReturn(
just(true).delay(3, TimeUnit.SECONDS)
)
}
Please look at JMockit. It has extensive documentation with a lot of examples. Here you have an example solution of your problem (to simplify I've added constructor to Seasons to inject mocked RainOnTrees instance):
package jmockitexample;
import mockit.Mocked;
import mockit.Verifications;
import mockit.integration.junit4.JMockit;
import org.junit.Test;
import org.junit.runner.RunWith;
#RunWith(JMockit.class)
public class SeasonsTest {
#Test
public void shouldStartRain(#Mocked final RainOnTrees rain) {
Seasons seasons = new Seasons(rain);
seasons.findSeasonAndRain();
new Verifications() {{
rain.startRain();
}};
}
public final class RainOnTrees {
public void startRain() {
// some code here
}
}
public class Seasons {
private final RainOnTrees rain;
public Seasons(RainOnTrees rain) {
this.rain = rain;
}
public void findSeasonAndRain() {
rain.startRain();
}
}
}
Solutions provided by RC and Luigi R. Viggiano together is possibly the best idea.
Although Mockito cannot, by design, mock final classes, the delegation approach is possible. This has its advantages:
You are not forced to change your class to non-final if that is what your API intends in the first place (final classes have their benefits).
You are testing the possibility of a decoration around your API.
In your test case, you deliberately forward the calls to the system under test. Hence, by design, your decoration does not do anything.
Hence you test can also demonstrate that the user can only decorate the API instead of extending it.
On a more subjective note:
I prefer keeping the frameworks to a minimum, which is why JUnit and Mockito are usually sufficient for me. In fact, restricting this way sometimes forces me to refactor for good as well.
If you trying to run unit-test under the test folder, the top solution is fine. Just follow it adding an extension.
But if you want to run it with android related class like context or activity which is under androidtest folder, the answer is for you.
Add these dependencies for run mockito successfully :
testImplementation 'org.mockito:mockito-core:2.24.5'
testImplementation "org.mockito:mockito-inline:2.24.5"
Mocking final classes is not supported for mockito-android as per this GitHub issue. You should use Mockk instead for this.
For both unit test and ui test, you can use Mockk with no problem.
If you need to use Mockito in an instrumented test in Android (i. e. running in an Android device), you cannot use mockito-inline. There is a special mockito-android version which doesn't solve the "final class" problem either. The only solution which seems to work is the Dexmaker library. The only limitation is that it works only in Android P (Android 9, API 28) and higher. It can be imported as follows:
androidTestImplementation "com.linkedin.dexmaker:dexmaker-mockito-inline:2.28.1"
Beware that there is also a "dexmaker-mockito" version which doesn't work for final classes either. Make sure you import "dexmaker-mockito-inline".
As others have stated, this won't work out of the box with Mockito. I would suggest using reflection to set the specific fields on the object that is being used by the code under test. If you find yourself doing this a lot, you can wrap this functionality in a library.
As an aside, if you are the one marking classes final, stop doing that. I ran across this question because I am working with an API where everything was marked final to prevent my legitimate need for extension (mocking), and I wish that the developer had not assumed that I would never need to extend the class.
For us, it was because we excluded mockito-inline from koin-test. One gradle module actually needed this and for reason only failed on release builds (debug builds in the IDE worked) :-P
For final class add below to mock and call static or non static.
1- add this in class level
#SuppressStatucInitializationFor(value ={class name with package})
2- PowerMockito.mockStatic(classname.class) will mock class
3- then use your when statement to return mock object when calling method of this class.
Enjoy
I was able to overcome this message:
org.mockito.exceptions.base.MockitoException:
Cannot mock/spy class org.slf4j.impl.Log4jLoggerAdapter
Mockito cannot mock/spy because :
final or anonymous class
from this: log = spy(log);
By using this instead:
log = mock(Logger.class);
Then it works.
I guess that "default" logger adapter is an instance of a final class so I couldn't "spy" it, but I could mock the whole thing. Go figure...
This may mean that you could substitute it for some other "non final" instance if you have that handy, as well. Or a simplified version, etc. FWIW...
I am writing the steps I followed after various unsuccessful attempts to mock final/private classes and their methods in Java 11, which finally worked for me.
Create a file named org.mockito.plugins.MockMaker inside
your test/resources/mockito-extensions folder. Please create
mockito-extensions folder if not present already.
Add a single line mock-maker-inline as the content of the above org.mockito.plugins.MockMaker file
Add
#RunWith(PowerMockRunner.class)
#PowerMockIgnore({"javax.management.*", "jdk.internal.reflect.*", "com.sun.org.apache.xerces.*", "javax.xml.*", "org.xml.*", "org.w3c.*"})
#PrepareForTest(Utility.class)
annotations at the class level.
Setup process in the test class
#Before
public void setup () {
MockitoAnnotations.initMocks(this);
Mockito.mockStatic(ClassToBeMocked.class);
}
Use Mockito.when(..).thenReturn(..) for assertions
In case of multiple test cases, add the below code
#After
public void after() {
Mockito.framework().clearInlineMocks();
}
The mockito version which I am using: 3.9.0
Java version: 11
Didn't try final, but for private, using reflection remove the modifier worked ! have checked further, it doesn't work for final.

Extending PHPUnit_Framework_TestCase while using dataProviders

I'm fairly new to using PHPUnit and I'm trying to use it more effectively by using data providers. I can get data providers to work when writing a normal test case, however I find that I'm rewriting my setup code for across several testcases. So I'm trying to extend PHPUnit_Framework_TestCase with a BaseTestCase class that does all of my common setup. This works if I run simple test in a test case that extends my BaseTestCase class. However I can't seem to use #dataProvider when extending my BaseTestCase class.
So my setup is:
class BaseTestCase extends PHPUnit_Framework_TestCase{
public static function setUpBeforeClass(){
//do setup
//this is getting called and it works
}
}
class myTest extends BaseTestCase{
public function myBasicTest(){
//this works
$this->assertEquals(2, 1+1);
}
public function myProvider(){
return [
[1,1,2],
[1,2,3],
[1,4,5],
]
}
/**
* #dataProvider myProvider
*/
public function testMyProvider($a, $b, $result){
//this doesn't work, the provider never gets called
//this would normally work if I extended PHPUnit_Framework_TestCase
$this->assertEquals($result, $a+$b);
}
}
I know the providers get ran before any of the setup does so I'm wondering if PHPUnit doesn't know that the provider exists because of the inheritance. Either way, does anyone know if what I'm trying to do is possible this way or does PHPUnit have another way of accommodating these types of situations?
Thanks for your help,
Jordan
Your test function does not begin with the word 'test'.
public function test_myProviderTest($a, $b, $result){
This is actually a non issue. I had an incorrect constructor setup in my test file. A very frustrating oversight.

Unit Testing: How to test a subclass in isolation from its parent?

I'm getting started unit testing my PHP application with PHPUnit. I understand that it's important for unit tests to run in isolation so you know where to look when a test fails. One thing I am struggling to understand is how to test subclasses in isolation from their parent. For example, most of my models extend a "base model" which has most of the features that a model should have.
<?php
class BaseModel
{
public function save($data) {
// write $data to the database
$dbAdapter->save($data);
}
}
class RegularModel extends BaseModel
{
public function save($data) {
// clean up $data before passing it to parent
if (isset($data['foo'])) {
unset($data['foo']);
$data['bar'] = 'foo';
}
parent::save($data);
}
}
# Unit Test
class RegularModelTest extends PHPUnit_Framework_TestCase
{
public function testSaveMethodCallsParent() {
$data = array('foo' => 'yes');
$model = new RegularModel();
$model->save($data);
// assert parent received data correctly
}
}
I'm not sure how to test my RegularModel without calling a bunch of unnecessary code. I'm also doing some autoloading so when it calls save on the parent, it will actually try to save to the test database. I'd rather mock this out since I don't care about whether or not it actually writes to the database when I'm testing my RegularModel only when I am testing my BaseModel. Or am I thinking about this all wrong? What do you recommend when it comes to testing situations like this?
Your best bet is to mock the $dbAdapter when testing RegularModel. While you are still executing the parent class's code, that code really is part of the RegularModel unit due to the is-a relationship.
The only way around it would be to provide a different implementation of BaseModel. You can either run these tests in a separate process or use Runkit to swap in the other implementation at runtime. Both of these have drawbacks--complexity, performance degredation, and instability--that come at too high a price in my view.
Subclasses are, by definition, tightly coupled to their superclasses so practically speaking there is no way to test a subclass in isolation.
However, if the superclass has an extensive test suite that passes then you normally can be confident that you can test the subclass by just covering the methods implemented in the subclass. The superclass test suite covers the superclass functionality.

How To Write CRUD Unit Tests for Moq and Linq-to-Sql

I am just getting involved in Moq and unit testing, so forgive me if this seems obvious (a quick search through SO didn't show me anything like this).
I have an interface with the following proposed member:
void AddFeed(Feed feed);
That I would like to write a unit test for this functionality. The test class has a Moq Repository declared as follows:
static IFeedRepository MockFeedsRepository(params Feed[] feeds)
{
var mockFeedsRepository = new Moq.Mock<IFeedRepository>();
mockFeedsRepository.Expect(x => x.Feeds).Returns((feeds.AsQueryable));
return mockFeedsRepository.Object;
}
How should the mock repository declaration be modified to include this new desired behavior or should I create a different Moq (and just how would that be done).
My assumption is that after creating the mock, deriving the unit test will be much easier but hints are greatly appreciated.
Many thanks,
KevDog
I'm also assuming that you would use the AddFeed method like this
Feed myNewFeed = new Feed();
feedRepository.Add(myNewFeed);
and that you're not using it like this (which is poor design)
IFeedRepository feedRepository = new FeedRepository();
Feed myNewFeed = new Feed(feedRepository);
...
myNewFeed.Save();
I'm going to guess that you would want to then have a test something like this:
[Test]
public void TheTest()
{
IFeedRepository repository = MockFeedsRepository({feed1, feed2, feed3});
Feed newFeed = new Feed();
repository.Add(newFeed);
Assert.AreEqual(4,repository.Count());
}
If that's the case then the test isn't actually testing anything other than your implementation of a mock in-memory repository. Is that what you really need to be doing?
I'd suggest that what you want to be doing is testing the L2Sql implementation of the repository instead, or testing how classes interact with the IFeedRepository interface.
And if you want to test the usage of the IFeedRepository interface then just do something simple like
[Test]
public void TheTest()
{
IFeedRepository repository = Moq.Mock<IFeedRepository>();
Feed newFeed = new Feed();
repository.Expect(r => r.Add(newFeed)); //no return as it's a void method
//repository.Expect(r => r.Add(newFeed)).Throws(new ApplicationException()); --Test handing of exceptions
//Code to hit the .Add() method
//Assert the Add method was called.
}
For tips on asserting if a method was called, see Using Moq to determine if a method is called
I hope that helps