For quick experiments, I prefer to use "unit tests" –i.e. annotating one (or more) method with [TestMethod]– over creating a tiny project with a Main method.
A test method has some advantages over a tiny project:
it is quicker to write a method and annotate it with [TestMethod] than to create a new project;
the test method can use facilities provides by the visual studio test tools such as test fixtures shared with similar experiments (via [TestInitialize]);
the method can be executed by right clicking and selecting "Run test" (in visual studio 2015);
and,
using Assert() instead of inspecting a value via the debugger or via Console.WriteLine() automatically documents the intent and the results of the experiment and makes it repeatable without manual intervention.
A problem is that these experiments show up in the visual studio test explorer, this causes clutter and makes it difficult to distinguish real unit tests from experiments. (I'm not using any other testing reporting tools, CI, etc., but I assume that the problem would occur there as well.)
Is there a way to have the advantages of using [TestMethod] for experiments and avoid the clutter that it causes at the same time?
I tried the following to solve this problem:
Have the [TestClass] and the [TestMethod] attributes as comments and uncomment them when you want to run the experiment.
This is what I currently do. It works, but running an experiment is somewhat cumbersome.
Use [Ignore] attribute.
Clutters the test explorer view with ignored tests and requires commenting out the [Ignore] attribute to run the test.
Put experiments in different project; as suggested by Veverke or annotate the test with a [TestCategory] attribute as suggested by C Sharper.
The visual studio test explorer can group tests by either class, duration, outcome, traits, project. To avoid the clutter: Choosing traits allows to keep the tree of tests annotated with [TestCategory("Experiments")] closed or choosing projects allows keeping the "experiments.proj" tree closed.
When using the grouping to distinguish experiments from tests, the other groupings in the test explorer cannot be used.
TL;DR
How to write experiments (using visual studio unit tests) without the experiments cluttering the reports about real unit tests?
Combining the answers:
Do you REALLY want to abuse unit tests as experiments? (comment by Jamie Rees and in answer by C Sharper)
Perhaps Linqpad ([https://www.linqpad.net/]) or something similar is better for experiments.
If you want to abuse unit tests, mark each experiment method with a [TestCategory]. This allows grouping the experiments in the test explorer and selecting which tests to run.(From answer by C Sharper)
Use a build configuration to define a conditional compilation symbol, for example EXPERIMENTS. Use #if EXPERIMENTS to enable or disable the experiments. Use a solution build configuration to be able to enable or disable the experiments from the toolbar.(From answer by Kasper van den Berg
Example:
#if EXPERIMENTS
[TestClass]
public class MyExperiment1
{
[TestMethod, TestCategory("Experiment")]
public void Method1()
{
…
}
}
#endif
Basically you misuse Unit Tests for something for which it was not intended.
But the only solution that comes in my mind is to use [TestCategory] attribute to control when a test runs and in which list it should be.
[TestMethod(), TestCategory("Nightly"), TestCategory("Weekly"), TestCategory("ShoppingCart")]
public void DebitTest()
{
}
Experiments can be disabled via an ifdef, e.g.:
#if EXPERIMENTS
[TestClass]
public class MyExperiment1
{
[TestMethod]
public void Method1()
{
…
}
}
#endif
To enable the experiment add #define EXPERMIMENTS as first line the file; however, this is still cumbersome. The conditional compilation symbol (EXPERIMENTS) can also be defined via project properties. To improve on this, create an build configuration and a solution configuration and define the conditional compilation symbols only for the build configuration.
Related
We're using Microsoft's Unit Test program and we use the Unit Test Wizard to create one-to-one mapping for methods in each class from the business layer. The issue is the amount of work needed go through and determine if we are missing any tests after the initial tests were created.
Currently I have to run the wizard and look for tests that have a "1" appended to the default name [method][test]. Those with that name mean we have already have a test for that method. The ones without an append 1 mean those are methods that don't have a Unit Test that follow the default naming convention.
I'm wondering if there is away to map Unit Test to a method with attribute on the Method so it doesn't take as much work. And yes, I know if we were following TDD we would write the Unit Test first. We write the test in parallel to development (but sometimes in rush it is missed).
If you are using Visual Studio 2012 and have the appropriate version, it has proper code coverage analysis built in: "Run tests with code coverage".
Otherwise, you can use a diagnostic tool to run code coverage, such as NCover. You can do this from inside Visual Studio using TestDriven.net
I've written a class and want to test if it works well. For now I think the best way to do it is to create new console application referencing main project, then make new instance of my class and mess with it. This approach unlike others enables IntelliSense, using keywords (no full names for classes) and Debugging.
Anyone knows how to do it in more convenient way to do this without making new console app?
Using a console app to test your class is what I would call a "poor man's unit test."
You are on the right track in wanting to do this sort of testing and I (and most others on SO) would suggest using a unit testing framework of some sort to help you out. (Mocking may be important and useful to you as well.)
Here's the thing though. Regardless of what framework you use, or if you go with a console app to test your code, you do have to create a separate project, or a separate, significant chunk of code of some sort, to be able to execute tests properly and independently. That's just part of the process. It is an investment but don't let the extra work keep you from doing it. It will save a lot time, and your skin, a little while in the future. Maybe even next week.
Also, while you're looking up unit testing make sure to also study up on test-driven development (TDD.)
Unit testing is absolutely the way to go. Depending on what version of VS you are running, there may be unit testing functionality built in, or you may have to use an additional tool such as NUnit. Both options are good and will allow you to fully test your classes.
Bear in mind also, that a comprehensive suite of unit tests will make refactoring much easier in the long run as well. If you refactor and break your unit tests, you know you've made a boo-boo somewhere. :)
Unit testing is the way forward here> this is a good introductory article.
The basic concept of a unit test is that you isolate and invoke a specific portion of code and assert that the results are expected and within reason. For example lets say you have a simple method to return the square of a floating point number:
public float Square(float value)
{
return value * value;
}
A reasonable unit test would be that the method returns the correct value, handles negetive values etc:
Assert.AreEqual(25, Square(5));
Assert.AreEqual(100, Square(-10));
Unit tests are also a good way to see how your code handles edge cases:
Assert.Throws<OverflowException>(Square(float.MaxValue));
If you are using VS 2010, check out Pex and Moles...
http://research.microsoft.com/en-us/projects/pex/
The Console App approach is more of a test harness for your class, which is fine.
But you can also use a unit testing framework to test your class. Visual Studio has one built in or you can leverage something like NUnit.
Also, try the Object Test Bench in Visual Studio. It should allow you to create a new instance, modify and view properties, and call some methods. It usually only works with very simple apps, though.
If you use Visual Studio 2008 or higher you will be able to test your code using MSTest framework:
1.Open Test View window: Test/Windows/Test View;
2.Add new unit test project: right click on Solution in Solution Explorer/Add/New
Project/Test Project;
3.Remove all files apart from UnitTest.cs file in created test project;
4.Write your unit test in method under [TestMethod] attribute:
[TestClass]
public class UnitTest1
{
[TestMethod]
public void TestMethod1()
{
var ranges = new Ranges();
int sum = ranges.CountOccurrences(11);
Assert.AreEqual(128, sum);
}
}
5.Run your test from Test View window added in p.1
6.See test results in Test/Windows/Test Results window
I've created a test suite in NUnit that references several distinct unit test fixtures in various assemblies.
I've pretty much used the example code from NUnit's docs:
namespace NUnit.Tests
{
using System;
using NUnit.Framework;
using System.Collections;
public class AllTests
{
[Suite]
public static IEnumerable Suite
{
get
{
ArrayList suite = new ArrayList();
suite.Add(new VisionMap.DotNet.Tests.ManagedInteropTest.DotNetUtilsTest());
return suite;
}
}
}
}
My goal is to add several tests to the list above so I can run them all in a batch.
But when I try to load the DLL in NUnit's GUI I get this:
What am I doing wrong?
I'm aware that the docs say the GUI won't run suites, but I've tried the console as well. Can somebody please tell me what Suites are good for and how I can use them to achieve my goal?
I'm using nunit 2.5.0.9122.
Edit
Well, no answers are forthcoming. I found an alternative solution in the end: Categories. I group test fixtures by giving them appropriate categories and then I can run a subset of them in batch, while still ignoring another subset.
Still, very odd that this Suite feature seems to be completely broken.
Suites aren't really needed for anything much at all these days. If you only wanted to use them to specify which tests do and don't get run this is much better achieved with Category attributes. This is what you ended up doing, and sounds like the best solution to your problem.
However, for others' and future reference, you can still use Suites in Nunit. You have to run them from the console, and only using the /fixture option. For example, to run the suite you specified above, you'd run (assuming your class was compiled into an assembly AllTests.dll):
nunit-console /fixture:AllTests.Suite AllTests.dll
You won't see any evidence of or way to run suites in the GUI - this is noted in the documentation. You can however run them from the console that is built into the GUI using commands like the above.
I use suites in some of my testing because I have some odd use cases that require me to sometimes need to pass an argument to my test methods. I do this by creating a suite such as the below. So there are some uses for them, just none needed in your case.
[Suite]
public static IEnumerable MySuite
{
get
{
var suite = new ArrayList{new TestClass1(arg1), TestClass2(arg2)};
return suite;
}
}
Is there any reason why you are returning "IEnumerable" instead of "TestSuite"?
[Suite]
public static TestSuite Suite
Update
Reading the small-print at the bottom of the page at NUnit site, it looks like Suite type tests will not show in in the Gui runner, so I guess that's the issue :)
Suites are currently not displayed in the Gui or run automatically by either runner when they are encountered. The historical purpose of the Suite mechanism was to provide a way of aggregating tests at the top level of each run. Hence, they are only supported when used with the /fixture option on the console or gui command line.
Update 2
I'm not sure what you are trying to achieve with the "Suite" feature, but if you are trying to find a way of configuring a set of test assemblies to be run together, I have used "NUnit Test Projects" to do this in the past (it's just an xml config file listing test dlls). This allows a fixed set of test assembly references to be configured and then loaded into the GUI or run by the console runner:
http://www.nunit.org/index.php?p=multiAssembly&r=2.5.5
So I've written a class and I have the code to test it, but where should I put that code? I could make a static method Test() for the class, but that doesn't need to be there during production and clutters up the class declaration. A bit of searching told me to put the test code in a separate project, but what exactly would the format of that project be? One static class with a method for each of the classes, so if my class was called Randomizer, the method would be called testRandomizer?
What are some best practices regarding organizing test code?
EDIT: I originally tagged the question with a variety of languages to which I thought it was relevant, but it seems like the overall answer to the question may be "use a testing framework", which is language specific. :D
Whether you are using a test framework (I highly recommend doing so) or not, the best place for the unit tests is in a separate assembly (C/C++/C#) or package (Java).
You will only have access to public and protected classes and methods, however unit testing usually only tests public APIs.
I recommend you add a separate test project/assembly/package for each existing project/assembly/package.
The format of the project depends on the test framework - for a .NET test project, use VSs built in test project template or NUnit in your version of VS doesn't support unit testing, for Java use JUnit, for C/C++ perhaps CppUnit (I haven't tried this one).
Test projects usually contain one static class init methods, one static class tear down method, one non-static init method for all tests, one non-static tear down method for all tests and one non-static method per test + any other methods you add.
The static methods let you copy dlls, set up the test environment and clear up the test enviroment, the non-static shared methods are for reducing duplicate code and the actual test methods for preparing the test-specific input, expected output and comparing them.
Where you put your test code depends on what you intend to do with the code. If it's a stand-alone class that, for example, you intend to make available to others for download and use, then the test code should be a project within the solution. The test code would, in addition to providing verification that the class was doing what you wanted it to do, provide an example for users of your class, so it should be well-documented and extremely clear.
If, on the other hand, your class is part of a library or DLL, and is intended to work only within the ecosystem of that library or DLL, then there should be a test program or framework that exercises the DLL as an entity. Code coverage tools will demonstrate that the test code is actually exercising the code. In my experience, these test programs are, like the single class program, built as a project within the solution that builds the DLL or library.
Note that in both of the above cases, the test project is not built as part of the standard build process. You have to build it specifically.
Finally, if your class is to be part of a larger project, your test code should become a part of whatever framework or process flow has been defined for your greater team. On my current project, for example, developer unit tests are maintained in a separate source control tree that has a structure parallel to that of the shipping code. Unit tests are required to pass code review by both the development and test team. During the build process (every other day right now), we build the shipping code, then the unit tests, then the QA test code set. Unit tests are run before the QA code and all must pass. This is pretty much a smoke test to make sure that we haven't broken the lowest level of functionality. Unit tests are required to generate a failure report and exit with a negative status code. Our processes are probably more formal than many, though.
In Java you should use Junit4, either by itself or (I think better) with an IDE. We have used three environments : Eclipse, NetBeans and Maven (with and without IDE). There can be some slight incompatibilities between these if not deployed systematically.
Generally all tests are in the same project but under a different directory/folder. Thus a class:
org.foo.Bar.java
would have a test
org.foo.BarTest.java
These are in the same package (org.foo) but would be organized in directories:
src/main/java/org/foo/Bar.java
and
src/test/java/org/foo/BarTest.java
These directories are universally recognised by Eclipse, NetBeans and Maven. Maven is the pickiest, whereas Eclipse does not always enforce strictness.
You should probably avoid calling other classes TestPlugh or XyzzyTest as some (old) tools will pick these up as containing tests even if they don't.
Even if you only have one test for your method (and most test authorities would expect more to exercise edge cases) you should arrange this type of structure.
EDIT Note that Maven is able to create distributions without tests even if they are in the same package. By default Maven also requires all tests to pass before the project can be deployed.
Most setups I have seen or use have a separate project that has the tests in them. This makes it a lot easier and cleaner to work with. As a separate project it's easy to deploy your code without having to worry about the tests being a part of the live system.
As testing progresses, I have seen separate projects for unit tests, integration tests and regression tests. One of the main ideas for this is to keep your unit tests running as fast as possible. Integration & regression tests tend to take longer due to the nature of their tests (connecting to databases, etc...)
I typically create a parallel package structure in a distinct source tree in the same project. That way your tests have access to public, protected and even package-private members of the class under test, which is often useful to have.
For example, I might have
myproject
src
main
com.acme.myapp.model
User
com.acme.myapp.web
RegisterController
test
com.acme.myapp.model
UserTest
com.acme.myapp.web
RegisterControllerTest
Maven does this, but the approach isn't particularly tied to Maven.
This would depend on the Testing Framework that you are using. JUnit, NUnit, some other? Each one will document some way to organize the test code. Also, if you are using continuous integration then that would also affect where and how you place your test. For example, this article discusses some options.
Create a new project in the same solution as your code.
If you're working with c# then Visual Studio will do this for you if you select Test > New Test... It has a wizard which will guide you through the process.
hmm. you want to test random number generator... may be it will be better to create strong mathematical proof of correctness of algorithm. Because otherwise, you must be sure that every sequence ever generated has a desired distribution
Create separate projects for unit-tests, integration-tests and functional-tests. Even if your "real" code has multiple projects, you can probably do with one project for each test-type, but it is important to distinguish between each type of test.
For the unit-tests, you should create a parallel namespace-hierarchy. So if you have crazy.juggler.drummer.Customer, you should unit-test it in crazy.juggler.drummer.CustomerTest. That way it is easy to see which classes are properly tested.
Functional- and integration-tests may be harder to place, but usually you can find a proper place. Tests of the database-layer probably belong somewhere like my.app.database.DatabaseIntegrationTest. Functional-tests might warrant their own namespace: my.app.functionaltests.CustomerCreationWorkflowTest.
But tip #1: be tough about separating the various kind of tests. Especially be sure to keep the collection of unit-tests separate from the integration-tests.
In the case of C# and Visual Studio 2010, you can create a test project from the templates which will be included in your project's solution. Then, you will be able to specify which tests to fire during the building of your project. All tests will live in a separate assembly.
Otherwise, you can use the NUnit Assembly, import it to your solution and start creating methods for all the object you need to test. For bigger projects, I prefer to locate these tests inside a separate assembly.
You can generate your own tests but I would strongly recommend using an existing framework.
I've got a LOT of tests written for a piece of software (which is a GREAT thing) but it was built essentially as a standalone test in C#. While this works well enough, it suffers from a few shortcomings, not the least of which is that it isn't using a standard testing framework and ends up requiring the person running the test to comment out calls to tests that shouldn't be run (when it isn't desired to run the entire test 'suite'). I'd like to incorporate it into my automated testing process.
I saw that the Test Edition of VS 2008 has the notion of a 'Generic Test' that might do what I want, but we're not in a position to spend the money on that version currently. I recently started using the VS 2008 Pro version.
These test methods follow a familiar pattern:
Do some setup for the test.
Execute the test.
Reset for the next test.
Each of them returns a bool (pass/fail) and a string ref to a fail reason, filled in if it fails.
On the bright side, at least the test methods are consistent.
I am sitting here tonight contemplating the approach I might take tomorrow morning to migrate all this test code to a testing framework and, frankly, I'm not all that excited about the idea of poring over 8-9K lines of test code by hand to do the conversion.
Have you had any experience undertaking such a conversion? Do you have any tips? I think I might be stuck slogging through it all doing global search/replaces and hand-changing the tests.
Any thoughts?
If you use NUnit (which you should), you'll need to create a new test method for each of your current test methods. NUnit uses reflection to query the test class for methods marked with the [Test] attribute, which is how it builds its list of the tests that show up in the UI, and the test classes use the NUnit Assert method to indicate whether they've passed or failed.
It seems to me that if your test methods are as consistent as you say, all of those NUnit methods would look something like this:
[Test]
public void MyTest()
{
string msg;
bool result = OldTestClass.MyTest(out msg);
if (!result)
{
Console.WriteLine(msg);
}
Assert.AreEqual(result, true);
}
Once you get that to work, your next step is to write a program that uses reflection to get all of the test method names on your old test class and produces a .cs file that has an NUnit method for each of your original test methods.
Annoying, maybe, but not extremely painful. And you'll only need to do it once.
You're about to live through the idiom of "An Ounce of Prevention is worth a pound of cure". Its especially true in programming.
You make no mention of NUnit(which I think was bought by Microsoft for 2008, but don't hold me to that). Is there a paticular reason you didn't just use NUnit in the first place?