27 lines
796 B
JavaScript
27 lines
796 B
JavaScript
'use strict';
|
|
|
|
Object.defineProperty(exports, "__esModule", {
|
|
value: true
|
|
});
|
|
exports.default = awaitify;
|
|
// conditionally promisify a function.
|
|
// only return a promise if a callback is omitted
|
|
function awaitify(asyncFn, arity = asyncFn.length) {
|
|
if (!arity) throw new Error('arity is undefined');
|
|
function awaitable(...args) {
|
|
if (typeof args[arity - 1] === 'function') {
|
|
return asyncFn.apply(this, args);
|
|
}
|
|
|
|
return new Promise((resolve, reject) => {
|
|
args[arity - 1] = (err, ...cbArgs) => {
|
|
if (err) return reject(err);
|
|
resolve(cbArgs.length > 1 ? cbArgs : cbArgs[0]);
|
|
};
|
|
asyncFn.apply(this, args);
|
|
});
|
|
}
|
|
|
|
return awaitable;
|
|
}
|
|
module.exports = exports['default']; |