cppcheck complains about unreadVariable when used in template - c++

Question

Can someone explain to me why the following code for a unit test gives the error unreadVariable for n and k in cppcheck?
Combinations is a template class that calculates all combinations of n choose k but this should not matter here.
TEST(Combinations, ChooseOne)
{
const UINT8 n = 3;
const UINT8 k = 1;
Combinations<n, k> comb;
comb.calc();
std::vector< std::vector<UINT8> > _vui8Expect = { { 2 }, { 1 }, { 0 } };
EXPECT_THAT(comb.result, ::testing::ContainerEq(_vui8Expect));
}
I can change the code to the following and not get a cppcheck error anymore. But I do not like this, because it make the code less verbose. n, k are well defined quantities in statistics and they make it more clear in the call what is going on.
TEST(Combinations, ChooseOne)
{
Combinations<3, 1> comb;
comb.calc();
std::vector< std::vector<UINT8> > _vui8Expect = { { 2 }, { 1 }, { 0 } };
EXPECT_THAT(comb.result, ::testing::ContainerEq(_vui8Expect));
}

Answer 1

This is a known issue: http://trac.cppcheck.net/ticket/7542
So unless it will be fixed, the cppcheck will report this false positive.

Answer 2

I tried to put this in a comment, but here is a thought.
As far as I remember Google Tests is using TEST clause in a following manner:
TEST(test_case_name, test_name) {
... test body ...
}
I haven't personally encountered something similar, but in your case you have the very same name for the test case name, and the actual class you test.
To me it seems like some sort of name collision.
Have you tried renaming
TEST(Combinations, ChooseOne)
{
const UINT8 n = 3;
const UINT8 k = 1;
Combinations<n, k> comb;
comb.calc();
std::vector< std::vector<UINT8> > _vui8Expect = { { 2 }, { 1 }, { 0 } };
EXPECT_THAT(comb.result, ::testing::ContainerEq(_vui8Expect));
}
to a:
TEST(CombinationsTest, ChooseOne)
{
const UINT8 n = 3;
const UINT8 k = 1;
Combinations<n, k> comb;
comb.calc();
std::vector< std::vector<UINT8> > _vui8Expect = { { 2 }, { 1 }, { 0 } };
EXPECT_THAT(comb.result, ::testing::ContainerEq(_vui8Expect));
}