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global.Promise = require('bluebird');


Promise.resolve(42).then(val => console.log(val));

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const Benchmark = require('benchmark');

const suite = new Benchmark.Suite();


suite.
  add('new promise', function() {
    return new Promise((resolve, reject) => {});
  }).
  on('cycle', function(event) {
    console.log(String(event.target));
  }).
  on('complete', function() {
    console.log('Fastest is ' + this.filter('fastest').map('name'));
  }).
  run();

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$ ~/Workspace/libs/node-v8.17.0-linux-x64/bin/node ./bluebird.js 
new promise x 36,846,162 ops/sec ±0.66% (95 runs sampled)
Fastest is new promise
$
$ ~/Workspace/libs/node-v8.17.0-linux-x64/bin/node ./bluebird.js 
new promise x 12,244,609 ops/sec ±1.80% (84 runs sampled)
Fastest is new promise

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Promise.resolve().
  then(fn).
  catch(err => console.log(err));

function fn() {
  return new Promise((resolve, reject) => {
    setImmediate(() => reject(new Error('Oops')));
  });
}

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$ node ./test
Error: Oops
    at Immediate.setImmediate [as _onImmediate] (/app/test.js:8:31)
    at runCallback (timers.js:705:18)
    at tryOnImmediate (timers.js:676:5)
    at processImmediate (timers.js:658:5)

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global.Promise = require('bluebird');
global.Promise.config({ longStackTraces: true });

Promise.resolve().
  then(fn).
  catch(err => console.log(err));

function fn() {
  return new Promise((resolve, reject) => {
    setImmediate(() => reject(new Error('Oops')));
  });
}

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$ node ./test
Error: Oops
    at Immediate.setImmediate [as _onImmediate] (/app/test.js:10:31)
From previous event:
    at fn (/app/test.js:9:10)
    at runCallback (timers.js:705:18)
    at tryOnImmediate (timers.js:676:5)
    at processImmediate (timers.js:658:5)
From previous event:
    at Object.<anonymous> (/app/test.js:5:3)
    at Module._compile (internal/modules/cjs/loader.js:778:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
    at Module.load (internal/modules/cjs/loader.js:653:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
    at Function.Module._load (internal/modules/cjs/loader.js:585:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:831:12)
    at startup (internal/bootstrap/node.js:283:19)
    at bootstrapNodeJSCore (internal/bootstrap/node.js:623:3)

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const NativePromise = global.Promise;
global.Promise = require('bluebird');

async function run() { return 'Hello, World'; }

const p = run();
p instanceof NativePromise; 
p instanceof global.Promise;