27 lines
863 B
JavaScript
27 lines
863 B
JavaScript
const promiseToCallback = require('promise-to-callback')
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const noop = function () {}
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/**
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* A generator that returns a function which, when passed a promise, can treat that promise as a node style callback.
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* The prime advantage being that callbacks are better for error handling.
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*
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* @param {Function} fn The function to handle as a callback
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* @param {Object} context The context in which the fn is to be called, most often a this reference
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*
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*/
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module.exports = function nodeify (fn, context) {
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return function () {
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const args = [].slice.call(arguments)
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const lastArg = args[args.length - 1]
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const lastArgIsCallback = typeof lastArg === 'function'
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let callback
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if (lastArgIsCallback) {
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callback = lastArg
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args.pop()
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} else {
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callback = noop
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}
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promiseToCallback(fn.apply(context, args))(callback)
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}
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}
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