ExperimentalWarning: The fs.promises API is experimental

[alexilyaev]

Description

Updated to latest lint-staged and seeing this in the output:

git commit -m "Some message here"

husky > pre-commit (node v10.16.1)
(node:56061) ExperimentalWarning: The fs.promises API is experimental
  ✔ Preparing...
  ✔ Running tasks...
  ✔ Applying modifications...
  ✔ Cleaning up...
[lint-staged-bug 0fc8320] Test lint-staged not applying git add
 1 file changed, 7 insertions(+), 4 deletions(-)

Steps to reproduce

  "lint-staged": {
    "*.js": [
      "eslint --ignore-path .gitignore --fix --max-warnings 0"
    ]
  },
  "husky": {
    "hooks": {
      "pre-commit": "lint-staged"
    }
  },

The maintainer of husky says it's not on their side:
typicode/husky#661

Debug Logs

expand to view

$ npx lint-staged -d
  lint-staged:bin Running `[email protected]` +0ms
  lint-staged:bin Options parsed from command-line: { allowEmpty: false,
  concurrent: true,
  configPath: undefined,
  debug: true,
  maxArgLength: 131072,
  quiet: false,
  relative: false,
  shell: false } +1ms
  lint-staged Loading config using `cosmiconfig` +0ms
(node:2870) ExperimentalWarning: The fs.promises API is experimental
  lint-staged Successfully loaded config from `/Users/alex/www/Node/test/package.json`:
  lint-staged { '*.js':
  lint-staged    [ 'npm run eslint:base -- --fix --max-warnings 0',
  lint-staged      'npm run prettier:base -- --write' ],
  lint-staged   '*.{json,md,mdx}': [ 'npm run prettier:base -- --write' ] } +8ms
  lint-staged:cfg Validating config +0ms
Running lint-staged with the following config:
{
  '*.js': [
    'npm run eslint:base -- --fix --max-warnings 0',
    'npm run prettier:base -- --write'
  ],
  '*.{json,md,mdx}': [
    'npm run prettier:base -- --write'
  ]
}
...

Environment

• OS: macOS 10.14.6
• Node.js: v10.16.1
• lint-staged: v10.0.4

[iiroj]

Hey, thanks for the report. This does come from lint-staged, since I refactored its file operations to use fs.promises.

I simply went by the 10.X LTS API docs which don’t mention it’s experimental, but it seems this warning was only removed in Node.ja v12:

nodejs/node#26581

Maybe it’s better to return to use the callback api via util.promisify to suppress this warning. Let me open a PR.

[okonet]

🎉 This issue has been resolved in version 10.0.7 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀