In this article we analyze differences of the restore, reset, resetHistory and resetBehaviour functions in sinon, and how they behave depending on whether our sinon fakes are anonymous or they wrap existing properties. — A very common approach while working with sinon, as shown in their own documentation, is to call the function restore as part of Mocha’s afterEach hook. afterEach(function () { // completely restore all fakes created through the sandbox sandbox.restore(); });

If you have offline sessions enabled in Keycloak and there are lots of them stored in the database (e.g. more than 300k) you will notice that the time it takes to start up can be up to more than 20 minutes. In this article I will share some tips we…

Deep equal assertions are faster to implement but usually come with a dangerous lack of attention — Has anyone in your team ever said something like this? “It was covered by unit tests, but we were comparing it against the wrong value!” Most of the times I’ve heard that, there was a deep equal assertion involved. Deep equal assertions in Chai.js are extremely simple and fast to…

Asking this question might be a sign of underlying design flaws. And the first step to fix them. — Why you usually shouldn’t test them In her book Practical Object Oriented Design in Ruby, Sandi Metz enumerates the following reasons not to include private methods in unit tests: Redundancy: private methods are hidden inside public components that already have tests; a failure in them will always be exposed by an existing test.

The fastest promise in JavaScript is the one that has already been resolved! — The npm package pending-promise-recycler keeps track of promises in a pending state; that means ongoing promises that have not been resolved yet. If someone would try to create a new instance of one of those pending promises, pending-promise-recycler will reuse the one that is currently pending instead of unnecessarily creating…

Exploring scenarios in which we might want to deviate from the standard. — Normally, I’d say “no, you don’t”; because GET is for read operations and POST is meant for write (e.g. create) operations. But today I was reading the draft of some OpenAPI specifications, in which one of our REST API consumers suggested having a new endpoint to look up users by…

With the package “pending-promise-recycler”, we can save precious resources and avoid performing the same operation again and again by recycling pending promises. — Imagine the following scenario. We have an API that sometimes makes calls to a 3rd party service; for example, to retrieve a list of stores. Let’s assume that retrieving this list of stores is a very expensive and slow operation, averaging a response time of about 12 seconds.

And non-programmers too! — I’ve always considered my work-related memory to be subpar. I would often be asked whether I remember how we implemented X or why we chose option Y; and even though we did implement X and chose option Y three or four times, the answer would forever remain hiding on the…

Code keeps changing, there’s no doubt about that. We always do our best to set some rock solid code foundations when a new project starts, we even have one or two favorite functions that become the cornerstone of our beautiful program. “This function will be my rod when I walk…