It's common in JavaScript for code to run asynchronously. When you have code that runs asynchronously, Jest needs to know when the code it is testing has completed, before it can move on to another test. Jest has several ways to handle this.| jestjs.io
The Jest philosophy is to work great by default, but sometimes you just need more configuration power.| jestjs.io
One of Jest's philosophies is to provide an integrated “zero-configuration” experience. We want to make it as frictionless as possible to write good tests that are useful. We observed that when engineers are provided with ready-to-use tools, they end up writing more tests, which in turn results in stable and healthy code bases.| jestjs.io
Snapshot tests are a very useful tool whenever you want to make sure your UI does not change unexpectedly.| jestjs.io