HelpSystem.Tests.ps1 cannot handle culture not being defined

先查看 test/powershell/engine/Help/HelpSystem.Tests.ps1 中第 425 行和第 434 行附近的内容，然后比较 test/powershell/engine/Help/UpdatableHelpSystem.Tests.ps1 中第 438-441 行附近的 culture 处理。将当前 culture 设置为 Invariant Language (LCID 127) 后，运行受影响的 Help 测试。如果两个 full-help 测试都在该环境中无错误通过，则表示完成。

Prerequisites

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• Make sure you are able to repro it on the latest released version
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• Refer to Differences between Windows PowerShell 5.1 and PowerShell.

Steps to reproduce

Reproducible on 7.6.2.

The test "help should return full view without -Full switch" and "help should return full view even with -Full switch" have the problem, that they'll break if the current culture is Invariant Language (Invariant Country) (LCID 127). This can happen on Linux systems if the LANG etc. environment variables are left to C.UTF-8. In this situation, there's no Get-Help pages available in the current language - and thus no PARAMETERS section either on a "Full" help page, breaking the test.

In the past, UpdatableHelpSystem.Tests.ps1 has been fixed by 16558c94146e44422f9e5b4f0f917775def51087 and now sets a culture if LCID is 127. This test would need a similar fix.

Expected behavior

No error.

Actual behavior

[-] help should return full view without -Full switch 6ms
      Expected a value, but got $null or empty.
      425:         $gpsHelp | Where-Object {$_ -cmatch '^PARAMETERS'} | Should -Not -BeNullOrEmpty
      at <ScriptBlock>, /build/powershell/src/PowerShell/test/powershell/engine/Help/HelpSystem.Tests.ps1: line 425
    [-] help should return full view even with -Full switch 6ms
      Expected a value, but got $null or empty.
      434:         $gpsHelp | Where-Object {$_ -cmatch '^PARAMETERS'} | Should -Not -BeNullOrEmpty
      at <ScriptBlock>, /build/powershell/src/PowerShell/test/powershell/engine/Help/HelpSystem.Tests.ps1: line 434

Error details

Environment data

Name                           Value
----                           -----
PSVersion                      7.6.2
PSEdition                      Core
GitCommitId                    7.6.2-0-g0d3c290a8737d4252ee75c052d16190ffcdb7d19
OS                             Arch Linux
Platform                       Unix
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.4
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Visuals

No response