generator-website-starter/generators/app/templates/node_modules/yargs/build/lib/utils/is-promise.js

A website generator using semantic markup, SASS, Gulp, Imagemin and Browser-sync

export function isPromise(maybePromise) {
    return (!!maybePromise &&
        !!maybePromise.then &&
        typeof maybePromise.then === 'function');
}