Until now we had just a single file that contained both our tests and the function that's being tested. In real life you want the tested function to be separated from its tests. This way you can run the function, without running the tests with it.

To install Pester it is usually enough to just do Install-Module Pester -Force. And then follow it by Ready to draw the attention of passers-by, employees or event guests? Look to time-tested custom posters. It’s easier than you may think to create a stylish personalised poster that gets noticed.

It is also a base for tools that validate whole environments, computer deployments, database configurations and so on. Become a financial contributor and help us sustain our community. Contribute to Pester Open Collective. Individuals If you look closer on how we broke the test, you can see that there are two distinct ways to break it. The error is: Expected 1, but got 8., this again reflects exactly what we did in the test, but it no longer reflects the real world. How tests break ​

If you do not need to test your scripts against PowerShell Core, just simply remove the entire line mentioning Ubuntu. Save this code example in a file named Get-Planet.Tests.ps1, and run Invoke-Pester Get-Planet.Tests.ps1, or just press F5 in VSCode. Pester runs on Windows, Linux, MacOS and anywhere else thanks to PowerShell. It is compatible with Windows PowerShell 3, 4, 5, 6 and 7. The first was that the tested function did not work correctly, this is a good way to break the test.Being able to distinguish between those two is important, when your test breaks keep in mind that either the function, or the tests might be broken. What you usually do is that you look at what changed more recently. If the test is new, and the function existed for a while, you first blame the test. When the test was passing before, but it is not anymore, you first blame the tested function. Other keywords ​ The second one is when the function works correctly, but the test is incorrect. This is a bad way to break the test.