Node.js: Testing and Code Quality

Course details

Most software engineers would agree that clean code is easier to maintain than messy code, but what exactly does that look like, and how do go about cleaning up messy code? In this course, Jon Peck shows how to measure quality, implement testing, and measure code coverage in your Node.js apps, using a complete but buggy restaurant booking application to illustrate the concepts. Jon first reviews JavaScript fundamentals and testing and code quality concepts. He then explains how to use linters to find suspicious code; explores different testing frameworks and their components; and shows how to isolate your code for testing using test doubles, then verify with spies and mocks. Jon wraps up the course by showing how to generate reports on code health across your entire codebase. Along the way, he provides challenge and solution videos so you can test your knowledge of each section before moving on.

Concepts

0. Introduction

01 - Cleaning your codebase
02 - What you should know
03 - Preparing for Node.js development
04 - Exercise files
05 - Demo setup and tour

1. Testing and Code Quality Fundamentals

06 - What is code quality
07 - Coding conventions and standards
08 - Creating and enforcing coding standards
09 - Unit, integration, and functional testing
10 - Testing frameworks
11 - TDD and BDD test specifications
12 - Assertions for correctness
13 - Challenge - Organize your tests
14 - Solution - Organize your tests

2. Finding Errors with Linting

15 - Standardizing with EditorConfig
16 - Adding EditorConfig to a project and IDE
17 - Comparing JavaScript linters
18 - Installing ESLint
19 - Configuring ESLint
20 - Extending an ESLint shareable config
21 - Linting your codebase
22 - Fixing code in VSC with ESLint
23 - Challenge - Create a shareable ESLint config
24 - Solution - Create a shareable ESLint config

3. Validate Correctness with Unit Testing

25 - Survey of Node.js testing frameworks
26 - Install Jest in a Node.js project
27 - What and where to unit test
28 - Writing your first Jest unit test
29 - Running a test suite with Jest
30 - Testing asynchronous callbacks with Jest
31 - Writing callback test suites with Jest
32 - Testing promises with Jest
33 - Challenge - Test async await with Jest
34 - Solution - Test async await with Jest

4. Replacing and Inspecting Using Spies, Stubs, and Mocks

35 - Replacing code with test doubles
36 - Mocking functions for test code
37 - Writing your first Jest mock
38 - Mock an entire module with Jest
39 - Mocking module dependencies
40 - Spying to observe interactions
41 - Challenge - Mock a successful reservation creation
42 - Solution - Mock a successful reservation creation

5. Reporting on Your Entire Codebase

43 - Why code coverage matters
44 - Measuring code coverage with Jest
45 - Functional testing with Jest
46 - Test doubles and Express apps
47 - Form submissions with SuperTest
48 - Fallacies of 100 test coverage
49 - Coverage with continuous integration
50 - Challenge - Isolate routes for faster tests
51 - Solution - Isolate routes for faster tests

Conclusion

52 - Testing and code quality goals
53 - Where to go from here

Node.js: Testing and Code Quality

Authors

Jon Peck