LibGit2Sharp can't find native assembly under PowerShell Core

I maintain a PowerShell module, GitAutomation, that wraps the LibGit2Sharp library. Yesterday, I was trying to get it to run on PowerShell Core. It doesn't seem to work. It is looking for the native git assembly in the LibGit2Sharp.dll assembly's folder instead of the lib/win32/xXX folder, like it does under Windows PowerShell (.NET Framework).

The issue appears to be your check for whether or not you're running under .NET Core. It looks like you're looking for the Mono.Runtime type, which doesn't exist in the version of .NET Core that PowerShell Core is using.

It looks like the current best way to determine if you're running under .NET Core is to use the System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription property, which begins with .NET Framework when running under the .NET Framework and .NET Core when running under .NET Core.

Windows PowerShell:

$ [Runtime.InteropServices.RuntimeInformation]::FrameworkDescription
.NET Framework 4.7.3260.0
$ [Mono.Runtime]
Unable to find type [Mono.Runtime].
At line:1 char:1
+ [Mono.Runtime]
+ ~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (Mono.Runtime:TypeName) [], RuntimeException
    + FullyQualifiedErrorId : TypeNotFound

PowerShell Core

 $ [Runtime.InteropServices.RuntimeInformation]::FrameworkDescription
.NET Core 4.6.26919.02
 $ [Mono.Runtime]
Unable to find type [Mono.Runtime].
At line:1 char:1
+ [Mono.Runtime]
+ ~~~~~~~~~~~~~~
+ CategoryInfo          : InvalidOperation: (Mono.Runtime:TypeName) [], RuntimeException
+ FullyQualifiedErrorId : TypeNotFound

首先在 LibGit2Sharp 原始碼中定位執行階段檢查和原生組件解析。分別在 PowerShell Core 和 Windows PowerShell 下重現查找過程，然後確認在這兩個環境中都能從 lib/win32/xXX 資料夾找到原生組件。當 GitAutomation 能夠在 PowerShell Core 上載入 LibGit2Sharp 時，即表示完成。