Catching custom error not working in Bluebird

Question

I am trying to throw and then catch a custom error in a Bluebird promise chain, but I can\'t get it to catch the custom error. For example:

function login(re         


        

Answer 1

Bluebird distinguishes error constructors from predicate functions in a catch by their inheritance:

For a parameter to be considered a type of error that you want to filter, you need the constructor to have its .prototype property be instanceof Error.

Such a constructor can be minimally created like so:

function MyCustomError() {}
MyCustomError.prototype = Object.create(Error.prototype);

You will need to do the same for your LoginError.

Or if you're using ES6, then class LoginError extends Error {}.