Michael Feathers–style legacy code change — treat code without automated tests as legacy, then follow identify change points, find test points, break dependencies, add tests (often characterization), and only then modify or refactor. Covers seams (object/link/preprocessing), sensing vs separation, fakes/mocks, sprout/wrap, pinch points, effect sketches, and dependency-breaking patterns. Composes with bugfix, TDD, and refactoring once a harness exists. Roadmap id: add-tests-to-legacy-code. Use when changing untested code, introducing a test seam, or adding coverage before a risky edit.
How to install legacy-testing?
dan-the-dev/xp-developer-skills/legacy-testing
$npx -y skills add dan-the-dev/xp-developer-skills --skill legacy-testingInstalls into the current project.
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Run `npx skills use "https://github.com/dan-the-dev/xp-developer-skills" --skill "dan-the-dev/xp-developer-skills/legacy-testing"` and follow the generated skill instructions now. Read its complete output, redirecting it to a temporary file first if necessary. Resolve relative paths from the supporting-files directory it provides.
Use the skills in "https://github.com/dan-the-dev/xp-developer-skills" that are relevant to the current task. Run `npx skills add "https://github.com/dan-the-dev/xp-developer-skills"` and select the relevant skills, then follow their instructions.
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