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Introduction JS: Advanced Testing

Testing is a big topic with lots of nuances. Testing pure functions is one thing, but testing an application with database interaction, sending network queries, emails, and using timers and asynchrony is another. Even error testing has its own peculiarities.

By organizing these tests properly, maintaining them won't be too difficult, and you'll be able to work much faster. If it's done wrong, however, it's very easy to fall into the trap of seemingly having tests, but they're hard to write, keep breaking, and you have to rewrite them often.

This course is about how to test complex situations with side effects, and asynchronous code, including code bound to timers. Main topics:

  • Error Testing. Snapshot tests.
  • Fixtures. Organizing test data.
  • Isolating side effects. Stubs. Dependency inversion.
  • Moki. Black box testing.
  • Timers. Time management.
  • Testing asynchronous code.

Further reading

Since this is an advanced testing course, it expects a certain amount of knowledge on your part. Below is a list of what you might need in different lessons to fully understand them:

  • Modules for working with the file system: fs, path <!---* HTTP--->

Recommended materials

  1. JavaScript Testing Best Practice

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