TDD with NestJS

Thiago Zilli Sarmento

2020 May

So why TDD test?

Just a few reasons (of many)...

 

• Find bugs early...

 

• Find regressions before someone else finds them...

 

• Supports easier implementation refactoring...

 

• Pseudo documentation in code...

 

• etc...

Responsibility of test

Just a few reasons (of many)...

 

 

• Tests must be part of Continuous Integration...

 

 

• Tests must be part of Continuous Deploy...

 

 

• Tests must be part of work flow... (sap)

 

Test Driven Development (TDD)

What to test?

 

• Database interactions...

 

• API endpoints (end-to-end)...

 

• Metrics...

 

• Test A and Test B behavior... and more

 

70% code coverage is required for basic metrics!

Testing Principles

 

 

• Avoid having side effects in your functions

 

• Tests should NOT rely on testing order (run independently)

• Tests should be repeatable

• Bogus your inputs

 

Thanks

 

 

Resorces

 

• https://nestjs.com/

• https://jestjs.io/

• https://github.com/visionmedia/supertest