Files
PowerShell-PowerShell/test/powershell
Dongbo Wang db45785341 Fix a module-loading regression that caused an infinite loop (#6843)
This regression was introduced by #6523, in `PSModuleInfo.cs`. A circular nested module check was removed because the comment there suggested it happens only with a deprecated workflow module. This causes a `StackOverflow` exception when running into circular nested modules.

Circular nested modules could happen for a module that is not well structured. For example, the module folder `test` contains two files: `test.psd1` and `test.psm1`, and `test.psd1` has the following content:
   @{ ModuleVersion = '0.0.1'; RootModule = 'test'; NestedModules = @('test') }

The same value `test` is put in both RootModule and NestedModule, which will end up with a module whose nested module points to itself.

There are two changes in this PR:
1. Add back the check for circular nested modules in `PSModuleInfo.cs`.
2. Remove a wrong `Dbg.Assert` in `ModuleCmdletBase.cs` and two checks before it.
   - For the assertion `Dbg.Assert(newManifestInfo.SessionState == ss`, when facing the example above, the nested module will first be loaded with a different session state, and then when trying to load the root module, the same loaded nested module will be reused for it. So 'newManifestInfo.SessionState' is not `ss`. The assertion will fail in that case.
   - For the two checks before the assertion, they are not needed anymore based on the comments there.
2018-05-10 16:09:36 -07:00
..

Pester Testing Test Guide

Also see the Writing Pester Tests document.

Running Pester Tests

First, restore the correct version of Pester using Restore-PSPester.

Then, 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 "pwsh"
    & $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.