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![Deloris Luckett](https://secure.gravatar.com/avatar/f14c0df648671d10acfbae7afd8588e9?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Deloris Luckett
6,418 PointsThe subtraction function in subtraction.js throws an error if it's called with anything other than numbers. Write a spec
var expect = require('chai').expect
describe('subtraction', function () {
var subtraction = require('../WHEREVER')
it('only works with numbers', function () {
// YOUR CODE HERE
expect(function () {
subraction()
}).to.throw('subtraction only works with numbers !');
})
})
above is subtraction spec js
below is subtraction js function subtraction (number1, number2) { throw error('subtraction only works with numbers!') if (typeof number1 !== 'number' || typeof number2 !== 'number') { throw Error('subtraction only works with numbers!') } return number1 - number2 }
does anyone know why im not passing
var expect = require('chai').expect
describe('subtraction', function () {
var subtraction = require('../WHEREVER')
it('only works with numbers', function () {
// YOUR CODE HERE
})
})
function subtraction (number1, number2) {
if (typeof number1 !== 'number' || typeof number2 !== 'number') {
throw Error('subtraction only works with numbers!')
}
return number1 - number2
}
1 Answer
![Peter Lord](https://uploads.teamtreehouse.com/production/profile-photos/11550447/micro_2020-05-02_p.lord.jpg)
Peter Lord
10,034 PointsI don't know much about Chai specifically, however, the chai documentation states to do expect(badFn).to.throw(). More information can be found here https://www.chaijs.com/api/bdd/#method_throw
Below is the correct code to pass the quiz.
var expect = require('chai').expect
describe('subtraction', function () {
var subtraction = require('../WHEREVER')
it('only works with numbers', function () {
// YOUR CODE HERE
expect(function () {
subtraction()
}).to.throw('subtraction only works with numbers!');
})
})