TypeError: Object prototype may only be an Object or null: undefined

[bjyoungblood]

TypeError: Object prototype may only be an Object or null: undefined

[bjyoungblood]

I wasn't able to duplicate this in a project using TypeScript 2.7.2.

Can you provide a code sample that causes this error?

[andrewc89]

I am seeing this error as well in Typescript 2.7.2. It appears when I run tests with the following command:

mocha -r ts-node/register -r tsconfig-paths/register test/**/*.test.ts

Here is a (hopefully useful) snippet of the stack trace:

at Module._compile (module.js:662:30)
    at Module.m._compile (C:\Dev\senalysis-common\node_modules\ts-node\src\index.ts:402:23)
    at Module._extensions..js (module.js:673:10)
    at Object.require.extensions.(anonymous function) [as .ts] (C:\Dev\senalysis-common\node_modules\ts-node\src\index.ts:405:12)
    at Module.load (module.js:575:32)
    at tryModuleLoad (module.js:515:12)
    at Function.Module._load (module.js:507:3)
    at Module.require (module.js:606:17)
    at require (internal/module.js:11:18)

Here is the class from which the error is thrown:

import ExtendableError from 'es6-error';

import {FacebookApiError} from 'models/facebook';

export class FacebookError extends ExtendableError {
    fbTraceId?: string;

    constructor(error: FacebookApiError) {
        super(error.error_user_msg);
        this.fbTraceId = error.fbtrace_id;
    }
}

I copied the ExtendableError internals into my own class, BaseError, and extended that instead. This gives no error.

export class BaseError extends Error {
    constructor(message = '') {
        super(message);
    
        // extending Error is weird and does not propagate `message`
        Object.defineProperty(this, 'message', {
          configurable: true,
          enumerable : false,
          value : message,
          writable : true,
        });
    
        Object.defineProperty(this, 'name', {
          configurable: true,
          enumerable : false,
          value : this.constructor.name,
          writable : true,
        });
    
        if (Error.hasOwnProperty('captureStackTrace')) {
          Error.captureStackTrace(this, this.constructor);
          return;
        }
    
        Object.defineProperty(this, 'stack', {
          configurable: true,
          enumerable : false,
          value : (new Error(message)).stack,
          writable : true,
        });
      }
}

import {BaseError} from './baseError';
import {FacebookApiError} from 'models/facebook';

export class FacebookError extends BaseError {
    fbTraceId?: string;

    constructor(error: FacebookApiError) {
        super(error.error_user_msg);
        this.fbTraceId = error.fbtrace_id;
    }
}

[cpylua]

TL;DR: Turn on esModuleInterop compiler option. If this is not an option, go ahead copy-and-paste.

Take at a look at this post.

babel-plugin-add-module-exports doesn't play well with TypeScript.

Hope it helps.