Dan Travison
6a78e303ff
This change mitigates intermittent timeout failures in the access denied tests as well as fixes unintended cross-test dependencies. If PowerShell takes longer that 10 seconds to complete a race can cause the subsequent test to pick up the output file of the previous test and fail (i.e., the expected output error file already exists from the previous test because it was created by the long running PowerShell process after the second test started.) Worse case, the failure cascades causing the race to propagate through the remaining tests in the set. The fix is two fold: 1: Increase the timeout for waiting for the launched powershell process. (mitigation) 2: Ensure each uses a unique name for the error and done files to avoid polluting the next test.
Pester Testing Test Guide
Also see the Writing Pester Tests document.
Running Pester Tests
Go to the top level of the PowerShell repository and run: Start-PSPester
inside a self-hosted copy of PowerShell.
You can use Start-PSPester -Tests SomeTestSuite* to limit the tests run.
Testing new powershell processes
Any launch of a new powershell process must include -noprofile so that
modified user and system profiles do not causes tests to fail. You also must
take care to call the development copy of PowerShell, which is not the first
one on the path.
Example:
$powershell = Join-Path -Path $PsHome -ChildPath "powershell"
& $powershell -noprofile -command "ExampleCommand" | Should Be "ExampleOutput"
Portability
Some tests simply must be tied to certain platforms. Use Pester's
-Skip directive on an It statement to do this. For instance to run
the test only on Windows:
It "Should do something on Windows" -Skip:($IsLinux -Or $IsMacOS) { ... }
Or only on Linux and OS X:
It "Should do something on Linux" -Skip:$IsWindows { ... }
Pending
When writing a test that should pass, but does not, please do not skip or delete
the test, but use It "Should Pass" -Pending to mark the test as pending, and
file an issue on GitHub.