This answer to a question about C++ unit test frameworks suggests a possibility that had not occurred to me before: using C++/CLI and NUnit to create unit tests for native C++ code.
We use NUnit for our C# tests, so the possibility of using it for C++ as well seems enticing.
I've never used managed C++, so my concern is are there any practical limitations to this approach? Are many of you doing this? If so, what was your experience like?
We do this all of the time. We have many assemblies written with C++/CLI and use C# and NUnit to test them. Actually, since our goal is to provide assemblies that work well with C#, doing this makes sure that we have accomplished that.
You can also write NUnit tests in C++/CLI and call unmanaged C++. Probably the best way is the keep your pure unmanaged C++ in a lib, and then make a test assembly that uses NUnit and links to the lib.
It works very well and gives you the benefit of having parameterised tests as well as a common test runner and framework if you're in a mixed environment.
There are two downsides, neither of which is serious for most cases:
If you're being really picky, the tests are no longer being run in a purely native environment so there's an outside possibility that something may work under test but fail at runtime. I think you'd have to be doing something fairly exotic for this to matter.
You rely on your C++ code being able to be included into a C++/CLI program. Sometimes this can have clashes with headers and it forces your code to build OK with UNICODE. In general, this is a good thing as it uncovers crufty bits of code (like inconsistent use of Ansi variants of Win32 calls). Bear in mind that it's only the headers being included so what it may well show is that you are exposing headers at too high a level - some of your includes should probably be within your cpp implementation files.
My experience is that it is not possible to use NUnit to test C++ native code through C++/CLI because you will have trouble loading and using native code.
I have tried using nunit to load a basic c++/cli test dll linked against "just thread" which is an implementation of the c++ standard thread library.
Test dlls won't even load with the latest version of NUnit (2.6.2).
So definitely not the way to go!
I never used one, but isn't there a port? Perhaps http://cunit.sourceforge.net/documentation.html would work for you.
The biggest concern is the learning curve of the C++/CLI language (formerly Managed C++) itself, if the tests need to be understood or maintained by non-C++ developers.
It takes a minimum of 1-2 years of C++ OOP experience in order to be able to make contributions into a C++CLI/NUnit test project and to solve the various issues that arise between the managed-native code interfaces. (By contribution, I mean being able to work standalone and able to make mock objects, implement and consume native interfaces in C++/CLI, etc. to meet all testing needs.)
Some people may just never grasp C++/CLI good enough to be able to contribute.
For certain types of native software libraries with very demanding test needs, C++/CLI/NUnit is the only combination that will meet all of the unit testing needs while keeping the test code agile and able to respond to changes. I recommend the book xUnit Test Patterns: Refactoring Test Code to go along this direction.
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I am doing an assignment (implementing an algorithm), and I wanted to try, this time, implementing tests first. However, I simply do not know where to put them! Do I need to create a new project?
All the tutorials I have found mentioned what to write, but not the general method of proceeding when building a test suite.
I expected Monodevelop to have some kind of predefined structure (like a big "add test suite" button), but I could not find anything for FSharp.
Monodevelop seems to have many tools to deal with tests in a clean and principled way (it does have a big "run tests" button), therefore I thought I would structure my project so that Monodevelop "sees" my tests, so that I could use the tools from the graphical interface. It seems the most common way to write tests is to use NUnit, what if I use something else, like FsCheck?
I have stumbled upon a Github project called FSharpKoans, it seems to suggest that I should create a project called "MySolution.Test" inside a solution, is this the standard way?
What should be the type of the project then, is it a separate console application?
Thanks.
Yes, creating a separate "X.Test" project is the standard way of adding tests in .NET, F# is no exception here.
For testing framework, pick one that Monodevelop supports well if what you're looking for is IDE integration - NUnit sounds like a safe choice. You could conceivably use any framework in F# tests, so I would think what Monodevelop supports should dictate your choice here.
FsCheck is not a testing framework, it's a library for property-based testing that can be used in conjunction with any testing framework. You might want to look into it as it advocates a particularly interesting approach to testing, but it's by no means the only way or the required way of doing testing in F#.
Can anybody explain how can i call .net methods(from .dll) in my java code but i dont want to write/use C/C++ Code please expalin it Step by Step
You haven't given us any information to work off (How large are the two projects? Are you forced to use a specific CLR/JRE? Can they be two separate processes or do you just need to access a bunch of methods? Stuff like that), but I can point you in a general direction...
IKVM.NET is an implementation of Java that runs on the CLR. If you run your Java program in there, you can interop with any other .NET language easily.
If you can't use this for some reason, then you're probably going to have to embed Mono in your application and write some JNI bindings to start an instance of the CLR, then load and invoke your code.
If you've got a small amount of methods, consider just porting the code to Java instead of creating this huge system in order to get a small amount of functionality.
I can't explain it step by step because you haven't provided very much information as to what restrictions you have or how it needs to be done. Also, this isn't something trivial. You're trying to get two language runtimes to interact with each other without using native code, when native code is the only thing either runtime can interoperate with.
There are lots of oop languages, but I couldn't find any that has conveniences like garbage collection, but compiles natively to machine code. Sort of like between C and java/c#. One interesting language I found was Vala, but that's limited to the GNOME platform and is not that well-known
Go is probably closest.
But why on earth do you want it natively compiled anyway?
JIT compilation of portable bytecode has proved to be an extremely effective strategy. It compiles down to native code at runtime (so you get up to the performance of native code after the first few iterations) and it avoids the issues of having to build and manage platform-specific compiled binaries.
Are you thinking about C++? That is in high usage and can be compiled on nearly any (major) platform.
In the case you want to use an oo language that compiles down to native code you will "always" have to use header files and stuff as the elf format doesn't support oo (There is no class information in elf).In case you want to use classes from external libs you need to make the compiler aware somehow about the fact that there are classes, functions, etc. that are declared outside of your project. In C++ this is solved by the use of header files. So that's, I think, a major drawback in native object oriented languages. To resolve that issue a few tweaks would need to be made to elf/loader/linker in order to support the kind of features (like "linking" against "classes") you might expect. Even though mechanism for garbage collection could be implemented even in native languages. But that seems no good for os implementation.
There are C++ libs to do that for userspace apps like:
Boehm collector
Smart pointers
I am writing a winforms application and eventually I would like to write unit test for this application from the DAL, and Biz Objects layers etc.
Does someone know of a FREE tool that can recieve the path to an assembly and then output unit test stubs with matching signatures for the assembly.
Any configurable options like "public interfaces only", "test framework choice", "language choice" would be a plus.
I at least would need this tool to emit vb.net against nunit.
Thanks.
Seth
Last I heard, the recommended method of unit testing was to write them as you develop the functionality in a test first style. Auto-generating unit test stubs, in my mind, would just result in a whole bunch of unimplemented unit tests which add no value and will most likely have very awful generic names that don't describe the behavior being tested.
On the other hand, maybe I'm just misunderstanding your question...
Take a look at Pex from Microsoft Research.
MS Unit test build into VS2008 can create stubs (using Reflection) in your behalf.
I found it very useful in most cases.
There is a tool called Pex that not only makes the stubs, but also fills in tests for you. There's also a video online.
edit: Mark Seemann beat me to it! Hopefully the links are still useful.
Am looking for a regression test framework where I can add tests to.. Tests could be any sort of binaries that poke an application..
This really depends on what you're trying to do, but one of the features of the new Test::Harness (disclaimer: I'm the original author and still a core developer) is that if your tests output TAP (the Test Anything Protocol), you can use Test::Harness to run test suites written in multiple languages. As a result, you don't have to worry about getting "locked in" to a particular language because that's all your testing software supports. In one of my talks on the subject, I even give an example of a test suite written in Perl, C, Ruby, and HTML (yes, HTML -- you'd have to see it).
Just thought I would tell you guys what I ended up using..
QMtest ::=> http://mentorembedded.github.io/qmtest/
I found QMTest to full fill my needs. Its extensible framework, allows you to write very flexible test classes. Then, these test classes could be instantiated to large test suites to do regression testing.
QMTest is also very forward thinking, it allows for weak test dependencies and the creation of test resources. After a while of using QMTest, I started writing better quality tests. However, like any other piece of complex software, it requires some time to learn and understand the concepts, the API is documented and the User Manual give a good introduction. With sometime in your hand, I think QMTest is well worth it.
You did not indicate what language you are working in, but the xUnit family is available for a lot of different languages.
/Allan
It also depends heavily what kind of application you're working on. For a commandline app, for example, its probably easy enough to just create a shell script that calls it with a whole bunch of different options and compares its result to a previously known stable version, warning you if any of the output differs so that you can check whether the change is intentional or not.
If you want something more fancy, of course, you'll probably want some sort of dedicated testing framework.
I assume you are regression-testing a web application?
There are some tools in this kb article from Microsoft
And if I remember correctly, certain editions of Visual Studio also offer its own flavor of regression testing tools as well.
But if you just want a unit testing framework, the xUnit family does it pretty well.
Here's JUnit and NUnit.