Ignore __proto__ #13933

Activity

1. Ryan Cavanaugh (RyanCavanaugh)

   added

   Awaiting More FeedbackThis means we'd like to hear from more people who would be helped by this featureThis means we'd like to hear from more people who would be helped by this feature

   SuggestionAn idea for TypeScriptAn idea for TypeScript

   on Feb 7, 2017
2. felixfbecker commented on Feb 10, 2017

   

   Felix Becker (felixfbecker)

   on Feb 10, 2017

   Last edited by felixfbecker

   Contributor

   More actions

   This is extremely annoying. Consider this

   export const stepComponent = {
       bindings: {
           hasNextStep: '>',
           hasPreviousStep: '>',
           onNextStep: '&',
           onPreviousStep: '&'
       },
       controller: class StepController {
           public hasNextStep: boolean;
           public hasPreviousStep: boolean;
           public onNextStep: Function;
           public onPreviousStep: Function;
       }
   };
   
   angular.component('credentialsStep', {
       __proto__: stepComponent,
       bindings: {
           __proto__: stepComponent.bindings,
           user: '>'
       },
       controller: class CredentialsStepController extends stepComponent.controller {
   
           public credentialsForm: angular.IFormController;
           public user: any;
           public repeatedPassword: string;
       }
   });

   The credentialsComponent should be valid and have all properties of the stepComponent, instead it fails with

   [ts]
   Argument of type '{ __proto__: { bindings: { hasNextStep: string; hasPreviousStep: string; onNextStep: string; onPr...' is not assignable to parameter of type 'IComponentOptions'.
     Object literal may only specify known properties, and '__proto__' does not exist in type 'IComponentOptions'.
   
3. jolexxa commented on Mar 6, 2019

   

   Joanna May (jolexxa)

   on Mar 6, 2019

   More actions

   Also ran into this tonight while making custom error subclasses for Node. Was expecting TypeScript to ignore anything relating to .__proto__ or at least have a mechanism for avoiding it.

   class CustomError extends Error {
   	constructor (message?: string) {
   		// 'Error' breaks prototype chain here
   		super(message);
   
   		// restore prototype chain
   		const actualProto = new.target.prototype;
   
   		if (Object.setPrototypeOf) { Object.setPrototypeOf(this, actualProto); } else { this.__proto__ = actualProto; }
   	}
   }

   Credits:
   https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-2.html#support-for-newtarget

   https://stackoverflow.com/a/48342359
4. exedor commented on May 31, 2020

   

   jb (exedor)

   on May 31, 2020

   Last edited by exedor

   More actions

   Same here. I just ran into this using the following loop structure:

   for (let i in qList) { qList[i].prop1.trim(); qList[i].prop2.trim(); }

   It is a simple array of objects. The job of the loop is to iterate over all the objects and trim two of it's string properties. The documentation for typescript talks about iterating over the indexes of the array. The problem is after it's done doing that, the value of i changes from an index to 'contains' which is method on

   __proto__

   This is completely broke our application when we upgraded typescript to 2.9.2. It worked great on 1.8.
5. mike-marcacci commented on Oct 20, 2021

   

   Mike Marcacci (mike-marcacci)

   on Oct 20, 2021

   More actions

   Just as a note, a full solution for this is described in this RFC: #38385.