Error running PowerShell Tests in Visual Studio 2019

When using the PowerShell Test Adapter in Visual Studio we can discover the tests in our project, but when we try to run them we get the following message:

A parameter cannot be found that matches parameter name 'TestName'.

We use the following tests in our MyTest.Tests.ps1

BeforeAll {
Function Get-Planet ([string]$Name = '*') {
$planets = @(
@{ Name = 'Mercury' }
@{ Name = 'Venus' }
@{ Name = 'Earth' }
@{ Name = 'Mars' }
@{ Name = 'Jupiter' }
@{ Name = 'Saturn' }
@{ Name = 'Uranus' }
@{ Name = 'Neptune' }
) | ForEach-Object { [PSCustomObject] $_ }
``
$planets | Where-Object { $_.Name -like $Name }
}
}

Describe 'Get-Planet' {
It 'Given no parameters, it lists all 8 planets' {
$allPlanets = Get-Planet
$allPlanets.Count | Should -Be 8
}
}

Version 5.3.1 of Pester is installed (Get-Module -list Pester)
Version 16.11.1 of Visual Studio 2019 is installed

Does anyone have an idea what we have to fix?

This seems like a bug so I’ve opened an issue here: Test Explorer not working in VS 2019 · Issue #533 · ironmansoftware/issues · GitHub

Thank you, I’m looking forward to seeing the solution in the next release.