Changing untested code without breaking it

In general, Legacy Code was not designed to be testable. Putting the existing codebase into a test suite is a very challenging step.

Problem is: without tests, every code change is risky. How do you know if you broke something?

Let's see what can get in the way and how you can solve every obstacle. Let's put some automated tests on your codebase!

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Written by Nicolas Carlo who lives and works in Montreal, Canada 🍁
He founded the Software Crafters Montreal community which cares about building maintainable softwares.