Gerrit/Code review/fr

Ceci est un guide pour la relecture et la fusion (merge) des contributions aux dépôts de code Wikimedia, écrit principalement pour les développeurs assurant la fonction de relecteur de code.


 * Pour les développeurs qui soumettent leur code, voir Faire relire son propre code.
 * Pour une introduction à l'outil Gerrit (commenter le code; comparer les ensembles de correction), voir le Tutoriel Gerrit.

Objectifs

 * Fournissez des critiques rapides pour éviter la lente détérioration des performances et de l'intégrité des données stockées et les sentiments d'abandon. Les retours rapides encouragent les développeurs à continuer à participer et contribuent ainsi à élargir notre base de collaborateurs.
 * Soyez gentil. Les corrections des contributeurs sont des dons. Les relectures de code influencent la perception qu'a un bénévole à propos du projet entier.
 * A long terme, encouragez les contributeurs du code à devenir également des relecteurs.



Chercher des corrections à relire
Il y a beaucoup de code à relire. Comment décomposer la tâche en sous-tâches plus gérables ?

Plusieurs modèles de base existent :



Par projet
Si vous êtes un mainteneur de code, pensez à déclarer les notifications par courriel pour les nouvelles corrections dans vos projets (les dépôts) via les Projets suivis dans Gerrit. Vous pouvez aussi vous inscrire auprès du Robot relecteur de Gerrit qui va vous ajouter automatiquement en tant que relecteur pour chaque nouvelle correction.


 * Identifiez les principales parties du travail ou les ensembles de relectures associées. Une relecture rapide et chronologique peut être un bon moyen pour faire cela; mais vous pouvez aussi choisir un dépôt avec de nombreuses corrections ouvertes.
 * Ouvrez toutes les pages de correction dans les onglets différents d'une fenêtre de votre navigateur. Ouvrez les fichiers concernés dans un éditeur de texte.
 * Relisez dans leur intégrité les nouveaux fichiers ainsi que ceux qui ne vous sont pas familiers. Choisissez un ensemble de corrections avec une modification importante dans les fichiers associés et relisez les.



Par auteur

 * Choisissez un auteur avec (beaucoup) de corrections ouvertes, chargez-les dans Gerrit.
 * Parcourez les versions chronologiquement, ou traitez un sujet ou un répertoire à la fois.
 * Cette méthode permet au relecteur de connaître les développeurs individuellement : leurs compétences, leurs défauts et leurs intérêts. Le travail comporte une idée de progression et de continuité.

Si quelqu'un vous a déja ajouté en tant que relecteur potentiel et que vous savez que vous ne pourrez pas relire la correction, retirez simplement votre nom de la liste des relecteurs.



Nouveaux contributeurs de nos projets
Vous pouvez ajouter (certaines) des requêtes ci-dessous à votre menu en modifiant vos préférences utilisateur. Un nouveau contributeur est défini comme une personne qui a fourni de une à cinq modifications au total.


 * Open changesets by new contributors successfully verified by Jenkins bot and awaiting reviewer feedback
 * Review the patch if you are familiar with the repository and make a decision (CR±1 or CR±2).
 * Open changesets by new contributors successfully verified by Jenkins bot and approved by a reviewer (CR>0)
 * Help make a decision (CR±1, or CR-2, or CR+2 if you have +2 rights for the repository).
 * Open changesets by new contributors successfully verified by Jenkins bot and disapproved by a reviewer (CR<0)
 * Ask if the contributor needs any help and if the contributor plans to continue improving the changeset.
 * Open changesets by new contributors not successfully verified by Jenkins bot
 * Ask if the contributor needs any help and if the contributor plans to continue improving the changeset.
 * The results of the queries above are all included in this single query: All open changesets by new contributors



Ordre chronologique (et chronologique inverse)

 * Commencez par la correction ouverte la plus ancienne, relisez en progressant jusqu'à la fin de la liste. Alternativement, commencez par la dernière version et relisez chacun des diff à son tour jusqu'au dernier. Cette approche est acceptable pour des versions mineures, mais nécessite de basculer régulièrement entre les projets et leur contexte.



Liste des points de relecture à vérifier


Réellement désiré ?

 * La toute première question est de savoir si la contribution est une bonne idée. Si la contribution est inutile ou ne suit pas la direction et le but du projet, expliquez et fournissez vos commentaires avec de meilleures idées.

Général

 * Contributed code should work as advertised, that is, any bugs found in the code should be fixed. (But be careful not to blame the current developer for code written by a previous developer.)
 * Maintain backwards compatibility for stable interfaces if this is relatively simple to do.
 * Si une modification proposant une rupture est nécessaire pour faire des changements significatifs, assurez-vous de suivre la Politique des interfaces stables.
 * Read relevant bug reports or documentation.
 * Familiarize yourself with any relevant technical issues. Read relevant specifications or manual sections.

Performance

 * Code that is run many times in a request, or code that is run on startup, should be reviewed for performance (e.g. by a member of the Wikimedia Performance Team). Suspicious code may need to be benchmarked.
 * Any web-accessible code which is very inefficient (in time, memory, query count, etc.) should be flagged for a fix (e.g. by creating a performance task in Phabricator).
 * Database schema changes or changes to high-traffic queries should be reviewed by a database expert. (A corresponding Phabricator task should have the tag "schema-change" associated.)

Conception

 * Does this change make the user experience better or worse for end users? If it has a user experience or visual design impact, consider consulting  or the design mailing list, or one of the design maintainers.

Style

 * Ensure the coding style conventions are followed, such as whitespace, line length, brace placement, etc.

Lisibilité

 * Functions should do what their names say. Choosing the correct verb is essential, a get* function should get something, a set* function should set something.
 * Variables names should use English, abbreviations should be avoided where possible.
 * Doc comments on functions are preferred.
 * Overly-complicated code should be simplified. This usually means making it longer. For instance:
 * Ternary operators (?:) may need to be replaced with if/else.
 * Long expressions may need to be broken up into several statements.
 * Clever use of operator precedence, shortcut evaluation, assignment expressions, etc. may need to be rewritten.
 * Duplication, whether within files or across files, should be avoided.
 * It is bad for readability since it's necessary to play "spot the difference" to work out what has changed. Reading many near-copies of some code necessarily takes longer than reading a single abstraction.
 * It is bad for maintainability, since if a bug (or missing feature) is found in the copied code, all instances of it have to be fixed.
 * Some new developers might copy large sections of code from other extensions or from the core, and change some minor details in it. If a developer seems to be writing code which is "too good" for their level of experience, try grep'ing the code base for some code fragments, to identify the source. Guide the developer towards either rewriting or refactoring.
 * Taking shortcuts can be counterproductive, since the amount of time spent figuring out the shortcut and verifying that it works could have been spent just typing out the original idea in full.

Sécurité

 * The reviewer should have read and understood the security guide and should be aware of the security issues discussed there.
 * There should not be the remotest possibility of arbitrary server-side code execution. This means that there should be no eval or create_function, and no /e modifier on preg_replace.
 * Check for text protocol injection issues (XSS, SQL injection, etc.) Insist on output-side escaping.
 * Check any write actions for CSRF.
 * Be wary of special entry points which may bypass the security provisions in WebStart.php.
 * Be wary of unnecessary duplication of security-relevant MW core functionality, such as using $_REQUEST instead of $wgRequest, or escaping SQL with addslashes instead of $dbr->addQuotes.
 * Only if you work on ancient code: Check for register_globals issues, especially classic arbitrary inclusion vulnerabilities. (Register Globals has been removed in PHP 5.4.0 and MediaWiki ≥1.27 requires PHP ≥5.5.9.)
 * If in doubt, consider contacting the Wikimedia Security Team.

Architecture

 * Names which are in a shared (global) namespace should be prefixed (or otherwise specific to the extension in question) to avoid conflicts between extensions. This includes:
 * Global variables
 * Global functions
 * Class names
 * Message names
 * Table names
 * The aim of modularity is to separate concerns. Modules should not depend on each other in unexpected or complex ways. The interfaces between modules should be as simple as possible without resorting to code duplication.
 * Check against the Architecture Principles.

Logique

 * Décrivez les raccourcis et demandez au développeur de réaliser un travail plus propre.



Finaliser la relecture


Laisser un commentaire positif

 * If you want to help to review the code, but don't feel comfortable (yet) making the final decision, you can use  in Gerrit and indicate whether you've "verified" and/or "inspected" the code.
 * If the revision is good and has passed all tests above, mark it  in Gerrit. If you are particularly impressed by someone's work, say so in a comment. When you mark a commit with , you're saying:
 * I've inspected this code, and
 * the code makes sense, and
 * the code works and does something that we want to do, and
 * the code doesn't do anything that we don't want it to do, and
 * the code follows our development guidelines, and
 * the code will still make sense in five years.



Laisser un commentaire négatif

 * If the revision is trivial, broken and has no obvious value, mark the commit as "Code-Review -2"
 * If the revision has issues but also has some utility, or is showing signs of heading in the right direction, mark it  and add a comment explaining what is wrong and how to fix it. Never mark something   without adding a comment. If someone marks your code   it means that your code is good, but needs improvement.

You have to weigh up the costs and benefits of each course of action. If you reject the change completely, then that change will be lost, and the developer may be discouraged. If you tolerate the fault, the end product will suffer. If you fix it yourself, then you're letting yourself get distracted, and perhaps you're making the developer believe that it is acceptable to submit low-quality code and then let someone else worry about the details.

General guidelines on comment style, especially when giving negative feedback:
 * 1)  Focus your comments on the code and any objectively-observed behavior, not motivations; for example, don't state or imply assumptions about motivating factors like whether the developer was too lazy or unexperienced to do things right. Ask questions instead of making demands to foster a technical discussion: "What do you think about...?" "Did you consider...?" "Can you clarify...?"
 * 2)  Be empathetic and kind.  Recognize that the developer has probably put a lot of work in their idea, and thank them for their contribution if you feel comfortable and sincere in doing so. "Why didn't you just..." provides a judgement, putting people on the defensive. Be positive.
 * 3)  Let them know where they can appeal your decision.  For example, invite them to discuss the issue on wikitech-l or on IRC.
 * 4)  Be clear.  Don't sugarcoat things so much that the central message is obscured.
 * 5)  Most importantly, give the feedback quickly. Don't just leave negative feedback to someone else or hope they aren't persistent enough to get their contribution accepted.



Voir aussi

 * Gerrit/+2
 * Gerrit/Code review/Getting reviews
 * Git/Reviewers