title: how to fix 'parsing error: Unexpected token =>' in node?
body: <p>I am using firebase functions for stripe payment integration. This particular function used for register customer with stripe.</p>
  
  <p>Node version 10.15.3 ,</p>
  
  <p>npm version 6.9.0 ,</p>
  
  <p>"ecmaVersion": 6 in .eslintrc.json</p>
  
  <pre><code>const functions = require('firebase-functions');
  
  const admin = require('firebase-admin');
  admin.initializeApp(functions.config().firebase);
  
  const stripe = require('stripe')(functions.config().stripe.testkey)
  
  exports.createStripeCustomer = functions.auth.user()
  
            .onCreate(async (user) =&gt; {
               const customer = await
               stripe.customers.create({email: user.email});
               await admin.firestore()
                 .collection('stripe_customers')
                 .doc(user.uid)
                 .set({customer_id: customer.id});
  
             });
  
  </code></pre>
  
  <p>The code is same as the firebase platform provide on github example 
  <a href="https://github.com/firebase/functions-samples/blob/master/stripe/functions/index.js" rel="noreferrer">https://github.com/firebase/functions-samples/blob/master/stripe/functions/index.js</a></p>
  
  <blockquote>
    <p>Parsing error: Unexpected token =></p>
  </blockquote>
  
  <p>and if I change the "ecmaVersion": 6 to "ecmaVersion": 8 in .eslintrc.json</p>
  
  <pre><code>then error is .onCreate(async (user) =&gt; {
  
                              ^
  
  SyntaxError: Unexpected token (
  </code></pre>
  
  <p>I want to deploy function properly so that user can register on stripe and date store in firebase storage</p>