René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"API surface regression test to catch unintended exports","articleBody":"### What is the problem this feature will solve?\n\nSometimes we have internal-only methods/constants/classes unintentionally exposed to userland. After being exposed for a long enough time, they inevitably become used by someone, leaving Node.js with a choice: either cause breakage in userland, or keep awkward deprecated/legacy code for years.\n\n### What is the feature you are proposing to solve the problem?\n\n- Fixture with a list of all currently exposed properties (flat array of strings like `fs/promises.readFile`, `dns.lookup.[customPromisifyArgs].1`, etc.)\n- Test that recursively goes through `module.builtinModules`, builds the list, and asserts equality against the fixture\n- Script that would overwrite the fixture with current list using `./out/Release/node ./tools/update-api-surface.mjs`\n\nThis way, the test would fail if something unintended happened, and fixture updates would clearly indicate the additions to public API.\nThis is not 100% robust because it won't include prototypes of some objects created in runtime (for example, `fs.Stats` is accessible while `fs.BigIntStats` is not), but it would catch most of exposures.\n\n### What alternatives have you considered?\n\nTool (e.g. GitHub Actions workflow) that would compare public API surface against base commit and somehow report the changes if any.","author":{"url":"https://github.com/LiviaMedeiros","@type":"Person","name":"LiviaMedeiros"},"datePublished":"2025-06-11T13:17:18.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/58676/node/issues/58676"}