Can't reexport the named export 'BREAK' from non EcmaScript module (only default export is available) when including aws-amplify - lack of mjs file support

[DaveClissold]

Current behavior:

Have just upgraded to version 5.0.0 and it looks like there is a webpack config issue, missing *.mjs support, which is causing the @aws-amplify and graphql libraries from compiling. This worked in 4.12.1

aws-amplify/amplify-js#4299
graphql/graphql-js#1272

Error: Webpack Compilation Error
./node_modules/graphql/index.mjs 49:0-53:205
Can't reexport the named export 'BREAK' from non EcmaScript module (only default export is available)
 @ ./node_modules/@aws-amplify/pubsub/lib-esm/Providers/AWSAppSyncRealTimeProvider.js
 @ ./node_modules/@aws-amplify/pubsub/lib-esm/Providers/index.js
 @ ./node_modules/@aws-amplify/pubsub/lib-esm/index.js
 @ ./node_modules/aws-amplify/lib-esm/index.js
 @ ./cypress/support/custom/userLogin.ts
 @ ./cypress/support/custom/index.ts
 @ ./cypress/support/commands.ts
 @ ./cypress/support/index.ts

[jennifer-shehane]

@DaveClissold Can you provide a full example for how you get this error please? Thanks!

[DaveClissold]

@jennifer-shehane I have a custom function to login to the AWS Cognito service, which uses the aws-amplify library.

import Amplify, { Auth } from 'aws-amplify';


Amplify.configure({
  Auth: {
    region: Cypress.env('AWS_REGION'),
    userPoolId: Cypress.env('AWS_USERPOOLID'),
    userPoolWebClientId: Cypress.env('AWS_USERPOOLWEBCLIENTID'),
  }
})

export const awsLogin = async () => {
  const username = Cypress.env('TEST_USERNAME');
  const password = Cypress.env('TEST_PASSWORD')
  try
    {
      const user = await Auth.signIn(username, password);
      return user
    } 
  catch (error)
    {
      console.log('error signing in', error);
    }
}

Aws-amplify relies on graphql queries, whose library 'very kindly' uses .mjs files.

I get the error when launching the test. It fails during the loading of the test

[jebendfds]

Same thing here. Also using amplify.

[liadb]

Same issue when upgrading to Cypress 5 and using amplify

[jennifer-shehane]

I can recreate the error when including aws-amplify:

Repro

cypress/support/index.js

import Amplify from 'aws-amplify'

package.json

{
  "devDependencies": {
    "aws-amplify": "^3.0.24",
    "cypress": "5.0.0"
  }
}

4.12.1

The aws-amplify takes a really long time to load normally. see #7464

5.0.0