CODEWITHSUNDEEP
c++stringunit-testingvisual-c++std
sgryzko
sgryzko

Reputation: 2407

Why doesn't Assert::AreEqual in the VS UnitTesting framework work with std::string?

I am trying to do a unit test on some c++ code but am running into some trouble.

I have something similar to the following lines of code...

std::string s1 = obj->getName();
std::string s2 = "ExpectedName";
Assert::AreEqual(s1, s2, "Unexpected Object Name");

And I'm getting the following compiler error...

error C2665: 'Microsoft::VisualStudio::TestTools::UnitTesting::Assert::AreEqual' :
none of the 15 overloads could convert all the argument types

It seems like it should be a match with the following overload:

AreEqual<(Of <(T>)>)(T, T, String)

Isn't the above overload a template overload that should support any object, as long as arguments 1 and 2 are of the same type? Or am I missing something?

Is there some other way that I can accomplish this Assert?

Upvotes: 9

Views: 10735

Answers (4)

justromagod
justromagod

Reputation: 993

I believe solution is to us L prefix before string

      Assert::AreEqual<bool>(true, dict->IsBeginWith("", ""), L"Empty");

You can also try case it like this, which give you wrong results, but lead to right direction of understanding of issue

   Assert::AreEqual<bool>(true, dict->IsBeginWith("", ""), (wchar_t*)"Empty"); //Empty
   Assert::AreEqual(true, dict->IsBeginWith("A", "A"), (wchar_t*)"Empty2");
   Assert::AreEqual(true, dict->IsBeginWith("A", "a"), (wchar_t*)""); //CAPITAL LETTER Check

Upvotes: 1

M. K. Hunter
M. K. Hunter

Reputation: 1828

If we are trying to stay in un-managed C++, and we don't care what the error message looks like, this is probably a better option than the accepted answer:

Assert::IsTrue(s1==s2)

By better, I mean it is at least easy to read.

Upvotes: 3

sgryzko
sgryzko

Reputation: 2407

I hacked up a bit of a workaround so that integers are compared instead of strings:

Assert::AreEqual(0, s1.compare(s2), "Unexpected Object Name");

In the future, we will likely switch to native C++ unit testing, but in the meantime, this does the trick. Obviously the messaging for this isn't very helpful

Assert.AreEqual failed. Expected:<0>. Actual:<1>. Unexpected Trajectory Name

But it's better than nothing.

Upvotes: 1

ildjarn
ildjarn

Reputation: 62975

You're attempting to use the managed unit testing framework with native types – this simply isn't going to work without marshaling the objects into managed types first.

VS2012 now comes with a native C++ unit testing framework; using this framework instead, your code could work by changing "Unexpected Object Name" to a wide string (prefix with L) and calling the following overload:

template<typename T> 
static void AreEqual(
    const T& expected, 
    const T& actual, 
    const wchar_t* message = NULL, 
    const __LineInfo* pLineInfo = NULL)

Upvotes: 4

Related Questions