Adding tests to legacy C or C++ code can be a challenge. Code not designed to be tested won’t naturally be testable. Dependencies will be unmanaged and invisible. Getting that first test written will hurt, a lot. Don’t despair! The first test is the hardest, but subsequent tests are much easier.
Knowing what to do and what to expect, when you start adding tests to your legacy code, can ease the journey. This article will give you an idea of what to expect when getting that first bit of C or C++ into the test harness.