I would like to test this code with Pester, but without creating a .psm1 and without creating an extra .ps1.

# file GetSomething.ps1
function Get-Something
{
  'something'
}

Get-Something

The corresponding test according to Pester Docs:

#file GetSomething.Tests.ps1
BeforeAll {
  . $PSScriptRootGetSomething.ps1
}

Describe 'Get-Something' {
  It 'Gets something' {
      Get-Something | Should Be 'something'
  }
}

I found various articles online describing my issue in detail. For example https://jakubjares.com/2015/01/10/test-script-end-to-end/ is a very detailed explanation why you want to dot-source and why it is an issue with Pester. It lists possible solutions with pros and cons, but it is from 2015.

The best solution I could find was this post. The new BeforeAll looks like this:

BeforeAll {
  function Get-Functions($filePath)
  {
      $script = Get-Command $filePath
      return $script.ScriptBlock.AST.FindAll({ $args[0] -is [Management.Automation.Language.FunctionDefinitionAst] }, $false)
  }

  Get-Functions GetSomething.ps1 | Invoke-Expression
}

I would imagine that almost everyone using Pester has this issue. Is there any newer/better approach to fix this with Pester v5? I do prefer .psm1 modules mostly, but sometimes I prefer script and functions in a single file and still want to test the functions in an extra file.