follow-redirects: Dynamic loading of debug possibly incompatible with Jest

I am encountering this error in my test suite using nock 12.0.3 and axios 0.21.1. It seems to be intermittent as well.

TypeError: Cannot read property 'apply' of undefined
        at module.exports (/Users/brian.moran/repos/subscription-service/node_modules/follow-redirects/debug.js:15:9)
        at Object.request (/Users/brian.moran/repos/subscription-service/node_modules/follow-redirects/index.js:457:7)
        at dispatchHttpRequest (/Users/brian.moran/repos/subscription-service/node_modules/axios/lib/adapters/http.js:195:25)
        at new Promise (<anonymous>)
        at httpAdapter (/Users/brian.moran/repos/subscription-service/node_modules/axios/lib/adapters/http.js:46:10)
        at dispatchRequest (/Users/brian.moran/repos/subscription-service/node_modules/axios/lib/core/dispatchRequest.js:52:10)

I am able to “fix” the issue by adding if(debug === undefined) return; to debug.js

var debug;

module.exports = function () {
  if (!debug) {
    try {
      /* eslint global-require: off */
      debug = require("debug")("follow-redirects");
    }
    catch (error) {
      debug = function () { /* */ };
    }
  }
  
  // "fixes" TypeError: Cannot read property 'apply' of undefined 
  if(debug === undefined) return;
  debug.apply(null, arguments);
};

Is this a known issue or is perhaps my problem elsewhere?

About this issue

Original URL
State: closed
Created 3 years ago
Reactions: 3
Comments: 15 (2 by maintainers)

Commits related to this issue

fix: address jest testing issue (fixes #153) — committed to af-mikecrowe/follow-redirects by af-mikecrowe 3 years ago

Most upvoted comments

For those curious, I may have solved this incorrectly. It seems the root cause is the fact the file is named debug.js and it is running in jest. If you set a breakpoint right after the require statement, debug is undefined (the core issue). However, doing this:

require.resolve('debug')
Uncaught RangeError: Maximum call stack size exceeded

Apparently (and I’m just learning this), naming your module debug and requiring a module named debug is not supported. To test, I renamed the old file follow-debug.js and the problem is solved.

I’m not sure this warrants changing the fix, but I’m posting here for posterity

af-mikecrowe on Aug 18, 2021

it’s Jest related

It probably is. That’s the insight we needed! Jest does some magic hoisting.

RubenVerborgh on Aug 9, 2021