native-or-another

Guaranteed way for getting a Promise. Always native Promise if available, otherwise looks for common promise libraries and loads which is installed. Allows registering custom Promise implementation in node < 0.12 versions

Pretty much like any-promise, but works a bit different & better.

Let your library support any ES 2015 (ES6) compatible Promise and leave the choice to application authors. The application can optionally register its preferred Promise implementation and it will be exported when requiring any-promise from library code. –– any-promise

If no preference is registered, always defaults to native Promise, using native-promise detection. It defaults to global Promise for newer Node.js >= 0.12 versions. The browser version defaults to the window Promise, so polyfill or register as necessary.

Table of Contents

• Install
• Usage
  • Get a Promise, always
  • Custom Promise registration
  • Support for old Node.js versions
• Related
• Contributing
• Building docs
• Running tests
• Author
• License

(TOC generated by verb using markdown-toc)

Install

Install with npm

$ npm install native-or-another --save

or install using yarn

$ yarn add native-or-another

Usage

For more use-cases see the tests.

Examples assumes that they are ran in older node versions, meaning < 0.12, be aware of that!

Get a Promise, always

Use it as any other Promise. It will give you native Promise always, until node < 0.12 - in that case it will try to load one of the common promise libraries, otherwise it will throw with a useful message to signal your users to install some of these promise implementations or register other one.

const Promise = require('native-or-another')

const promise = new Promise((resolve, reject) => {
  resolve(123)
})

promise.then((res) => console.log('foo:', res))

Custom Promise registration

You can .register() a custom Promise which will be used by the main export. That function also returns that Promise. If no arguments are passed, it will try to load some of the common promise libraries, again.

const register = require('native-or-another/register')

const MyCustomPromise = () => 444
register({ Promise: MyCustomPromise })

const Promize = require('native-or-another')

// loads `MyCustomPromise`
const res = Promize()
console.log(res) // => 444

// but also adds it to global scope
const res = Promise()
console.log(res) // => 444

// but also adds it to global.Promise
const res = global.Promise()
console.log(res) // => 444

Notice that it adds the promise to global scope and global, if you don't want that behaviour you should disable it through passing an option to .register function, like { global: false }.

const register = require('native-or-another/register')
const Promize = register({ global: false })

console.log(Promize) // => function
console.log(Promise) // => undefined
console.log(global.Promise) // => undefined

This is exactly how require('native-or-another') works!

Support for old Node.js versions

Node.js versions prior to v0.12 may have contained buggy versions of the global Promise. For this reason, the global Promise is not loaded automatically for these old versions.
If using native-or-another in Node.js versions < v0.12, the user should register a desired implementation.

If an implementation is not registered, native-or-another will attempt to discover an installed Promise implementation. If no implementation can be found, an error will be thrown on require('native-or-another'). While the auto-discovery usually avoids errors, it is non-deterministic. It is recommended that the user always register a preferred implementation for older Node.js versions.

This auto-discovery is only available for Node.js versions before v0.12. Any newer versions (includeing v0.12) will always default to the global Promise implementation.

Adapted from the any-promise readme.

Related

• clean-stacktrace: Clean up error stack traces from node internals | homepage
• find-callsite: Finds the correct place where the stack trace was started, not the place where error was thrown | homepage
• native-promise: Get native Promise or falsey value if not available. | homepage
• redolent: Simple promisify with sane defaults, works on node 0.10 if you provide custom Promise through options | homepage
• stacktrace-metadata: Modify given err object to be more useful - adds at, line, column, place and filename properties… more | homepage
• try-catch-callback: try/catch block with a callback, used in try-catch-core. Use it when you don't care about asyncness so… more | homepage

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Please read the contributing guidelines for advice on opening issues, pull requests, and coding standards.
If you need some help and can spent some cash, feel free to contact me at CodeMentor.io too.

In short: If you want to contribute to that project, please follow these things

1. Please DO NOT edit README.md, CHANGELOG.md and .verb.md files. See "Building docs" section.
2. Ensure anything is okey by installing the dependencies and run the tests. See "Running tests" section.
3. Always use npm run commit to commit changes instead of git commit, because it is interactive and user-friendly. It uses commitizen behind the scenes, which follows Conventional Changelog idealogy.
4. Do NOT bump the version in package.json. For that we use npm run release, which is standard-version and follows Conventional Changelog idealogy.

Thanks a lot! :)

Building docs

Documentation and that readme is generated using verb-generate-readme, which is a verb generator, so you need to install both of them and then run verb command like that

$ npm install verbose/verb#dev verb-generate-readme --global && verb

Please don't edit the README directly. Any changes to the readme must be made in .verb.md.

Running tests

Clone repository and run the following in that cloned directory

$ npm install && npm test

Author

Charlike Mike Reagent

• github/tunnckoCore
• twitter/tunnckoCore
• codementor/tunnckoCore

License

Copyright © 2014, 2017, Charlike Mike Reagent. Released under the MIT License.

This file was generated by verb-generate-readme, v0.4.3, on March 17, 2017.
Project scaffolded using charlike cli.