1
0
mirror of https://github.com/kremalicious/metamask-extension.git synced 2024-11-27 12:56:01 +01:00
metamask-extension/app/scripts/lib/nodeify.js
Mark Stacey ac01c5c89a
Consistent jsdoc syntax (#7755)
* Specify type before parameter name

Various JSDoc `@param` entries were specified as `name {type}` rather
than `{type} name`.

A couple of `@return` entries have been given types as well.

* Use JSDoc optional syntax rather than Closure syntax

* Use @returns rather than @return

* Use consistent built-in type capitalization

Primitive types are lower-case, and Object is upper-case.

* Separate param/return description with a dash
2020-01-13 14:36:36 -04:00

41 lines
1.1 KiB
JavaScript

import promiseToCallback from 'promise-to-callback'
const callbackNoop = function (err) {
if (err) {
throw err
}
}
/**
* A generator that returns a function which, when passed a promise, can treat that promise as a node style callback.
* The prime advantage being that callbacks are better for error handling.
*
* @param {Function} fn - The function to handle as a callback
* @param {Object} context - The context in which the fn is to be called, most often a this reference
*
*/
export default function nodeify (fn, context) {
return function () {
// parse arguments
const args = [].slice.call(arguments)
const lastArg = args[args.length - 1]
const lastArgIsCallback = typeof lastArg === 'function'
let callback
if (lastArgIsCallback) {
callback = lastArg
args.pop()
} else {
callback = callbackNoop
}
// call the provided function and ensure result is a promise
let result
try {
result = Promise.resolve(fn.apply(context, args))
} catch (err) {
result = Promise.reject(err)
}
// wire up promise resolution to callback
promiseToCallback(result)(callback)
}
}