Legacy code refactoring
Refactor legacy code safely and incrementally by following SOLID principles and modern best practices.
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Tu es un expert en refactoring et en amélioration de code legacy. Voici un morceau de code [LANGAGE] écrit il y a [ANCIENNETÉ] qui doit être modernisé : ``` [COLLER_LE_CODE_LEGACY] ``` **Contexte du projet :** - Framework actuel : [EX: Express 4, Django 3] - Version cible après refactoring : [EX: Express 5, Django 5] - Contraintes : [EX: pas de changement d'API publique, tests existants doivent passer] - Dette technique identifiée : [DESCRIPTION_OPTIONNELLE] Effectue le refactoring en plusieurs étapes : **Étape 1 - Analyse :** Identifie les anti-patterns, la duplication de code, les responsabilités multiples (violation du SRP), les dépendances cachées et les risques de régression. **Étape 2 - Stratégie :** Propose un plan de refactoring incrémental qui permet de tester chaque étape indépendamment. Identifie les étapes critiques et les points de rollback. **Étape 3 - Code refactorisé :** Produis le code refactorisé complet avec des commentaires expliquant chaque changement important. Respecte les principes SOLID et les patterns appropriés. **Étape 4 - Tests :** Fournis des tests unitaires pour valider que le comportement est préservé après refactoring.
Why this prompt works
<p>This prompt is designed to approach refactoring as a methodical process rather than a haphazard rewrite. Breaking it down into four distinct steps (analysis, strategy, code, tests) ensures that the AI doesn't jump straight to code without understanding the constraints and risks.</p><p>Mentioning specific constraints (API compatibility, existing tests) is crucial because it forces the AI to produce realistic and deployable refactoring, not theoretical ideal code that would break backward compatibility.</p><p>Requesting validation tests in addition to the refactored code is a good practice that transforms this prompt into a retrospective TDD tool, allowing each refactoring step to be secured with an automated test suite.</p>
Use Cases
Expected Output
An analysis of the problems, an incremental refactoring plan, the refactored code and validation unit tests.
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