0.3.1 • Public • Published

    npm (scoped) license Standard Travis AppVeyor


    This package was moved to the @xpack scope.

    To install it use @xpack/es6-promisifier.

    There are no plans for further releases of this package in the @ilg scope.

    An ES6 promisifier wrapper

    A module providing a class with a static function to wrap standard Node.js callback functions into ES6 promises.


    A recent Node.js (>7.x), since the ECMAScript 6 class syntax is used.

    Easy install

    The module is available as @ilg/es6-promisifier from the public repository, use npm to install it inside the module where it is needed:

    $ npm install @ilg/es6-promisifier --save

    The module does not provide any executables, and generally there are few reasons to install it globally.

    The development repository is available from the GitHub xpack/es6-promisifier-js project.

    User info

    The module can be included in any applications and the Promisifier class can be used to access the promisify() functions.

    const Promisifier = require('@ilg/es6-promisifier').Promisifier
    // Promisify functions from the Node.js callbacks library.
    // The new functions have similar names, but suffixed with `Promise`,
    // or below a `promises` object.
    Promisifier.promisifyInPlace(fs, 'open')
    // New use case:
    //   const fsPromises = fs.promises_
    //   await fsPromises.open()
    // Old use case:
    //   await fs.openPromise()
    // Note: using `promises_` is a workaround to avoid the `fs.promises`
    // warning.
    // Promisify a single function from a third party simple module.
    const mkdirpPromise = Promisifier.promisify(require('mkdirp'))

    Developer info

    Git repo

    $ git clone https://github.com/xpack/es6-promisifier-js.git es6-promisifier-js.git
    $ cd es6-promisifier-js.git
    $ npm install
    $ sudo npm link 
    $ ls -l /usr/local/lib/node_modules/@ilg

    or without sudo, on Windows or if installed in home folder:

    $ npm link

    A link to the development folder should be present in the global node_modules folder.

    In projects that use this module under development, link back from the global location:

    $ npm link @ilg/es6-promisifier


    The tests use the node-tap framework (A Test-Anything-Protocol library for Node.js, written by Isaac Schlueter).

    As for any npm package, the standard way to run the project tests is via npm test:

    $ cd es6-promisifier-js.git
    $ npm install
    $ npm run test

    A typical test result looks like:

    $ npm run test
    > @ilg/es6-promisifier@0.1.2 test /Users/ilg/My Files/MacBookPro Projects/xPack/npm-modules/es6-promisifier-js.git
    > standard && npm run test-tap -s
    test/tap/promisify.js ............................... 32/32
    total ............................................... 32/32
      32 passing (669.026ms)

    To run a specific test with more verbose output, use npm run tap:

    $ npm run tap test/tap/promisify.js -s
      original success
        ✓ null error
        ✓ returned value
      original error
        ✓ have error
        ✓ error message match
        ✓ no returned value
      promisify success
        ✓ returned value
      promisify error
        ✓ exception message
      promisify success await
        ✓ returned value
      promisify error await
        ✓ exception message
      promisify multi success
        ✓ result is array
        ✓ first value
        ✓ second value
      promisify multi error
        ✓ exception message
      promisify multi success await
        ✓ result is array
        ✓ first value
        ✓ second value
      promisify multi error await
        ✓ exception message
      promisify single success
        ✓ result is not array
        ✓ value
      promisify single error
        ✓ exception message
      promisify single success await
        ✓ result is not array
        ✓ value
      promisify single error await
        ✓ exception message
      promisify already success await
        ✓ returned value
      promisify already error await
        ✓ exception message
      promisify thisArg success await
        ✓ returned value
        ✓ context value
      promisify thisArg error await
        ✓ exception message
        ✓ assert
      promisify in place
        ✓ promise not there
        ✓ promise now available
        ✓ promise still there
      32 passing (617.365ms)

    Coverage tests

    Coverage tests are a good indication on how much of the source files is exercised by the tests. Ideally all source files should be covered 100%, for all 4 criteria (statements, branches, functions, lines).

    To run the coverage tests, use npm run test-coverage:

    $ npm run test-coverage
    > @ilg/es6-promisifier@0.1.2 test-coverage /Users/ilg/My Files/MacBookPro Projects/xPack/npm-modules/es6-promisifier-js.git
    > tap --coverage --reporter=classic --timeout 600 --no-color "test/tap/*.js"
    test/tap/promisify.js ............................... 32/32
    total ............................................... 32/32
      32 passing (829.493ms)
    File                        |  % Stmts | % Branch |  % Funcs |  % Lines |Uncovered Lines |
    All files                   |      100 |      100 |      100 |      100 |                |
     es6-promisifier-js.git     |      100 |      100 |      100 |      100 |                |
      index.js                  |      100 |      100 |      100 |      100 |                |
     es6-promisifier-js.git/lib |      100 |      100 |      100 |      100 |                |
      promisifier.js            |      100 |      100 |      100 |      100 |                |

    Continuous Integration (CI)

    The continuous integration tests are performed via Travis CI and AppVeyor.

    To speed up things, the node_modules folder is cached between builds.

    Standard compliance

    The module uses ECMAScript 6 class definitions.

    As style, it uses the JavaScript Standard Style, automatically checked at each commit via Travis CI.

    Known and accepted exceptions:

    • none.

    To manually fix compliance with the style guide (where possible):

    $ npm run fix
    > @ilg/es6-promisifier@0.1.12 fix /Users/ilg/My Files/MacBookPro Projects/xPack/npm-modules/es6-promisifier-js.git
    > standard --fix

    Documentation metadata

    The documentation metadata follows the JSdoc tags.

    To enforce checking at file level, add the following comments right after the use strict:

    'use strict'
    /* eslint valid-jsdoc: "error" */
    /* eslint max-len: [ "error", 80, { "ignoreUrls": true } ] */

    Note: be sure C style comments are used, C++ styles are not parsed by ESLint.

    How to publish

    • commit all changes
    • npm run test (fix included)
    • update CHANGELOG.md; commit with a message like CHANGELOG: prepare v0.1.2
    • npm version patch
    • push all changes to GitHub; this should trigger CI
    • wait for CI tests to complete
    • npm publish


    The original content is released under the MIT License, with all rights reserved to Liviu Ionescu.



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