Building a good unit test for this requires checking both of these scenarios. If not, Add-Content will first be called with the Path parameter passed to it, and then Get-Content will be called right afterward. If Test-Path returns $true, Get-Content will be called, and the Path parameter value will be passed to it. This function can go two different ways, depending on what Test-Path returns. If (Test-Path -Path $Path -PathType Leaf)Īdd-Content -Path $Path -Value 'something in here' Let's start with a typical function that contains some logic and a few references to other commands inside. Unfortunately, creating custom objects within the Mock is not ideal when dealing with complex Mock objects with nested properties.
Mocking is a way to eliminate these command dependencies and test only your code-not the code of the other commands and not code that depends on some environmental factor. With Pester’s Mock function, we can isolate our code from this outside (hostile ) world by faking commands and make them return whatever we want, even a custom object. So how do you build a good unit test that has calls to other commands so you can be sure it's only testing your code and not the other commands referenced? Mocking. It's best never to trust any other command in your unit test. I started our like many of you by simply writing a script and manually trying different scenarios. Over the years, I have learned my lesson the hard way that everything should include some level of testing. One of the most critical aspects to any development project is a solid test plan. Mocks the behavior of an existing command with an alternate implementation. Verify that specific commands were (or were not) called. What if the drive you placed the file on was non-existent? At the same time, you're also depending on Get-Content and Add-Content working right. Unit Testing PowerShell Classes with Pester. Mock the behavior of ANY powershell command. In fact, it would be testing whatever storage system the file was on as well. This is not good practice as your unit test would not be testing just your code. This would test the functionality, but your unit test would then have a dependency on an environmental element (the file).
The function allows you to specify a script block that will. You could actually put a dummy file on your system somewhere, run your code, remove the file, and run your code again. This creates new behavior for any existing command within the scope of a Describe or Context block. A good unit test needs to contain each of these instances to ensure the code did what you thought it would do depending on the state of the file itself. They will always be evaluated last since they will act as a 'catch all' mock. The exception to this rule are Mocks with no filters. The mock of the first filter to pass will be used. The last one created will be the first to be evaluated. If not, you may then call Add-Content to create the file instead. ParameterFilters will be evaluated in reverse order of their creation. For example, if you have some code that checks for the existence of a file, you might then call Get-Content to read the contents.
0 kommentar(er)
