Fix `Module parse failed: Cannot read property 'length' of undefined`

[jebbench]

Fix for https://github.com/GoogleChromeLabs/worker-plugin/issues/93

Checks that optsExpr.properties is defined.

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[dcantu476]

Is there anything outstanding that would prevent this from being merged in? This fixed the issue I was having with the mentioned auth0 library.

[iplaksiy]

Seconding @dcantu476. Angular will not build unless I update this manually.

[mgreg89]

@developit Can you merge this PR? Would really appreciate it! :)

[AntonyChiossi]

Can you please merge this :) ? @developit

it causes also some problem with Web workers

steps:

• create new app
• follow https://angular.io/guide/web-worker
• create a class as follow

  export class WebWorker {
  protected worker;
  constructor(url: string, options?: WorkerOptions) {
  this.worker = new Worker(url, options);
  return this.worker;
  }
  }

• use it in the app.component.ts

  @Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss'],
  })
  export class AppComponent implements OnInit {
  title = 'angular-tour-of-heroes';
  result: string;
  
  ngOnInit() {
  const ww = new WebWorker('./app.y-worker', { type: 'module' });
  
  if (typeof Worker !== 'undefined') {
    const worker = new Worker('./app.y-worker', { type: 'module' });
    worker.onmessage = ({ data }) => {
      console.log(`page got message: ${data}`);
      this.result = `page got message: ${data}`;
    };
    worker.postMessage('hello');
  } else {
    // Web Workers are not supported in this environment.
    // You should add a fallback so that your program still executes correctly.
  }
  }
  }

  The project wont compile

  ERROR in ./src/app/randomname.ts
  Module parse failed: Cannot read property 'length' of undefined
  File was processed with these loaders:
  * ./node_modules/@ngtools/webpack/src/index.js
  You may need an additional loader to handle the result of these loaders.
  TypeError: Cannot read property 'length' of undefined
  at /home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/worker-plugin/dist/worker-plugin.js:64:44
  at SyncBailHook.eval [as call] (eval at create (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/tapable/lib/HookCodeFactory.js:19:10), <anonymous>:7:16)
  at Parser.walkNewExpression (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1822:25)
  at Parser.walkExpression (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1613:10)
  at Parser.walkAssignmentExpression (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1793:8)
  at Parser.walkExpression (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1583:10)
  at Parser.walkExpressionStatement (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1022:8)
  at Parser.walkStatement (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:964:10)
  at Parser.walkStatements (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:868:9)
  at /home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1017:9
  at Parser.inBlockScope (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:2060:3)
  at Parser.walkBlockStatement (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1014:8)
  at Parser.walkStatement (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:949:10)
  at /home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1702:10
  at Parser.inFunctionScope (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:2043:3)
  at Parser.walkFunctionExpression (/home/vm/to_delete/angular/angular-tour-of-heroes/node_modules/webpack/lib/Parser.js:1695:8)

  

more details can be found here:

https://github.com/ng-web-apis/workers/issues/7

[developit]

Apologies for taking so long to merge this.

[developit]

Published as 5.0.1.