6. Testing Express/Connect-based applications
Jest is great to test Express/Connect-based applications.
In this section you will learn to:
- use mock request and response objects to test express route handlers and middleware
- use supertest to test express routing, route handlers and middleware
The first involves testing only the request handlers by passing mock request and response objects.
The other leverages supertest to write test in-memory (no issues with port allocations), but with what’s essentially a full Express application, using supertest.