How to compare vectors with Boost.Test?

Question

I am using Boost Test to unit test some C++ code.

I have a vector of values that I need to compare with expected results, but I don't want to manually check the values in a loop:

BOOST_REQUIRE_EQUAL(values.size(), expected.size());

for( int i = 0; i < size; ++i )
{
    BOOST_CHECK_EQUAL(values[i], expected[i]);
}

The main problem is that the loop check doesn't print the index, so it requires some searching to find the mismatch.

I could use std::equal or std::mismatch on the two vectors, but that will require a lot of boilerplate as well.

Is there a cleaner way to do this?

Answer 1

Use BOOST_CHECK_EQUAL_COLLECTIONS. It's a macro in test_tools.hpp that takes two pairs of iterators:

BOOST_CHECK_EQUAL_COLLECTIONS(values.begin(), values.end(), 
                              expected.begin(), expected.end());

It will report the indexes and the values that mismatch. If the sizes don't match, it will report that as well (and won't just run off the end of the vector).

---

Note that if you want to use BOOST_CHECK_EQUAL or BOOST_CHECK_EQUAL_COLLECTIONS with non-POD types, you will need to implement

bool YourType::operator!=(const YourType &rhs)  //  or OtherType
std::ostream &operator<<(std::ostream &os, const YourType &yt)

for the comparison and logging, respectively.
The order of the iterators passed to BOOST_CHECK_EQUAL_COLLECTIONS determines which is the RHS and LHS of the != comparison - the first iterator range will be the LHS in the comparisons.

Answer 2

How about BOOST_CHECK_EQUAL_COLLECTIONS?

BOOST_AUTO_TEST_CASE( test )
{
    int col1 [] = { 1, 2, 3, 4, 5, 6, 7 };
    int col2 [] = { 1, 2, 4, 4, 5, 7, 7 };

    BOOST_CHECK_EQUAL_COLLECTIONS( col1, col1+7, col2, col2+7 );
}

example

Running 1 test case...

test.cpp(11): error in "test": check { col1, col1+7 } == { col2, col2+7 } failed.

Mismatch in a position 2: 3 != 4

Mismatch in a position 5: 6 != 7

* 1 failure detected in test suite "example"