chai: Cannot read property 'not' of undefined

Question

I am new to chai and mocha and I use the sample code for my first test case. Here is my code.

var chai = require(\"chai\");
var mocha =         


        

Answer 1

If I run your code with Chai 4, it works. When I downgrade it to Chai 3 I get the error you get. does was added as a no-op assertion in Chai 4.0.0. You are using a version of Chai that predates 4.0.0.

If you check the releases information, you'll find for version 4.0.0, this:

Add does and but as new no-op assertion. (Related Issues: #700, #339 PRs: #621, #701)

(You can find the same information in the Github release, with the added benefit that the issue numbers are links to the actual issues.)