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TDD and legacy code

Zeger Hendrikse edited this page May 22, 2024 · 10 revisions

Definition of legacy code

Michael Feathers

To me, legacy code is simply code without tests — Michael Feathers

The site maintained by Nicolas Carlo, understandlegacycode.com, boasts a blog post that summarizes the key points of Working Effectively with Legacy Code.

Nicolas himself uses a somewhat different definition of legacy code.

Nicolas Carlo

Legacy Code is valuable code you’re afraid to change — Nicolas Carlo

as you may sometimes encounter code without (sufficient) tests, but the code reveals its intention so well, that you're not afraid to modify it.

Practice materials

References

Nicolas Carlo shares tips & tricks to work with Legacy Code on his blog: understandlegacycode.com