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JavaScript

Posted by shu Chan
shu Chan
2,951 Points

Javascript Unit testing catching an error

Having an issue figuring out why this code doesn't seem to pass the challenge, I've narrowed it down to the difference between var and let to declare the handler but I don't understand exactly what problems the difference causes

var expect = require('chai').expect

describe('subtraction', function () {
  var subtraction = require('../WHEREVER')  
  it('only works with numbers', function () {
    let handler = function () {
            subtraction('a', 1);
        }
        expect (handler).to.throw('subtraction only works with numbers!');
  })
})