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).

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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.