Pester breaks on functions with unknown label

[iRon7]

Checklist

• [x] Issue has a meaningful title
• [x] I have searched the existing issues. See all issues
• [x] I have tested using the latest version of Pester. See Installation and update guide.

What is the issue?

Not sure whether this is a PowerShell a bug or feature but fixing it in PowerShell would probably be a break change.

A side effect of this "feature" is also that it breaks all running Pester tests:

Actual behavior

Starting discovery in 1 files.
Discovery found 3 tests in 47ms.
Running tests.

(no further results)

Expected Behavior

Starting discovery in 1 files.
Discovery found 3 tests in 38ms.
Running tests.
[-] Describe.Context.It 1 27ms (27ms|0ms)
 Expected $null or empty, but got 1.
 at Test 1 | Should -BeNullOrEmpty, C:\Users\Gebruiker\OneDrive\Scripts\PowerShell\PowerSnippets\ObjectGraph\ObjectGraphTools\_Temp\Test\Pester\Test.ps1:13
 at <ScriptBlock>, C:\Users\Gebruiker\OneDrive\Scripts\PowerShell\PowerSnippets\ObjectGraph\ObjectGraphTools\_Temp\Test\Pester\Test.ps1:13
[-] Describe.Context.It 2 37ms (36ms|1ms)
 Expected $null or empty, but got @(1, 2).
 at Test 2 | Should -BeNullOrEmpty, C:\Users\Gebruiker\OneDrive\Scripts\PowerShell\PowerSnippets\ObjectGraph\ObjectGraphTools\_Temp\Test\Pester\Test.ps1:17
 at <ScriptBlock>, C:\Users\Gebruiker\OneDrive\Scripts\PowerShell\PowerSnippets\ObjectGraph\ObjectGraphTools\_Temp\Test\Pester\Test.ps1:17
[-] Describe.Context.It 3 28ms (27ms|1ms)
 Expected $null or empty, but got @(1, 2, 3).
 at Test 3 | Should -BeNullOrEmpty, C:\Users\Gebruiker\OneDrive\Scripts\PowerShell\PowerSnippets\ObjectGraph\ObjectGraphTools\_Temp\Test\Pester\Test.ps1:21
 at <ScriptBlock>, C:\Users\Gebruiker\OneDrive\Scripts\PowerShell\PowerSnippets\ObjectGraph\ObjectGraphTools\_Temp\Test\Pester\Test.ps1:21
Tests completed in 282ms
Tests Passed: 0, Failed: 3, Skipped: 0 NotRun: 0

Or at least:

Tests completed in ...
Tests Passed: ..., Failed: ..., Skipped: ... NotRun: ...

Or an error message

Steps To Reproduce

Function Test($b) {
    :foo foreach ($a in 1,2,3) {
        $a
        if ($a -ge $b) { break bar }
    }
}

Describe 'Describe' {

    Context 'Context' {

        It 'It 1' {
            Test 1 | Should -BeNullOrEmpty
        }

        It 'It 2' {
            Test 2 | Should -BeNullOrEmpty
        }

        It 'It 3' {
            Test 3 | Should -BeNullOrEmpty
        }
    }

}

Describe your environment

Pester version     : 5.5.0 C:\Users\Gebruiker\Documents\PowerShell\Modules\Pester\5.5.0\Pester.psm1                     
PowerShell version : 7.5.4
OS version         : Microsoft Windows NT 10.0.26100.0

Possible Solution?

Check for unknown labels during discovery?