Using Approval Tests With Boost.Test

Introduction

The Boost.Test test framework works well with Approval Tests.

Note: this document assumes the reader is familiar with the Boost.Test framework.

Requirements

Approval Tests for Boost.Test requires that you specify the #include <.../unit_test.hpp>

This allows ApprovalTests to work with all the different configurations of boost.

Approval Tests needs Boost.Test version 1.60.0 or above.

Getting Started With Boost.Test

Adding ApprovalTests to your Boost.Test

To enable any Boost.Test test files to use ApprovalTests, find the corresponding entry point and

add the following lines of code to your Test module’s entry point after the boost headers:

// test_entry_point.cpp file[s] (after #including boost.test)
#define APPROVALS_BOOSTTEST
#include "ApprovalTests.hpp"

(See snippet source)

Understanding Boost.Test Entry points

A directory of Boost.Test source files can either have multiple or a single entry point[s]. The entry point is any file that will contain the line:

#define BOOST_TEST_MODULE ModuleName

(See snippet source)

Code to copy for your first Boost.Test Approvals test

Here is sample code to create your main() function, to set up Approval Tests’ Boost.Test integration.

We called this file boost_starter_main.cpp:

#define BOOST_TEST_MODULE ModuleName

//#include <boost/test/unit_test.hpp> // static or dynamic boost build
#include <boost/test/included/unit_test.hpp> // header only boost

#define APPROVALS_BOOSTTEST
#include "ApprovalTests.hpp"

// This puts "received" and "approved" files in approval_tests/ sub-directory,
// keeping the test source directory tidy:
auto directoryDisposer =
    ApprovalTests::Approvals::useApprovalsSubdirectory("approval_tests");

(See snippet source)

Here is sample code to create your first test. We called this file boost_starter_test.cpp:

#define BOOST_TEST_INCLUDED
#include <boost/test/unit_test.hpp>

#include "ApprovalTests.hpp"

BOOST_AUTO_TEST_SUITE(SuiteName)
BOOST_AUTO_TEST_CASE(TestCaseName)
{
    ApprovalTests::Approvals::verify(42);
}
BOOST_AUTO_TEST_SUITE_END()

(See snippet source)

And finally, here is sample code to put in your CMakeLists.txt file:

set(EXE_NAME boost_starter)
set(CMAKE_CXX_STANDARD 11)

find_package(Boost 1.60.0 COMPONENTS REQUIRED)
if (NOT Boost_FOUND)
    message(FATAL_ERROR "Cannot find Boost libraries")
endif ()

include_directories(SYSTEM ${Boost_INCLUDE_DIRS})

add_executable(${EXE_NAME}
        boost_starter_main.cpp
        boost_starter_test.cpp
        )
target_link_libraries(${EXE_NAME} ApprovalTests::ApprovalTests ${Boost_LIBRARIES})

add_test(NAME ${EXE_NAME} COMMAND ${EXE_NAME})

(See snippet source)