No logic in tests

conditionals.ps1

#ex1
# say not to this one
$configuration:Servers | foreach {
  It "A test" {
    # code
  }
}

# use this instead
It "A test" -TestCases @(
     @{ Server = "server1"},
     . . . 
) {
    # code
  }
}

# if you DO need to generate the list of test cases dynamically, do it in a function that is tested.
# Pester currently does not fail when you provide 0 testcases, so look out for lack of data that allows
# your tests to pass 

#(this is also common problem with foreach in tests, 
#no items in collection -> no it block runs -> no fails -> passing tests that did not test anything)


#ex2
# say no to this one
if ($PSVersionTable.PsVersion.Major -ge 5){
  It "A test running only on powershell 5="{
    # code
  }
}

# write this (and test it!) instead
Invoke-OnPowerShell5OrLaterOnly {
  It "A test" {
    # code
  }
}

# feel free to come up with a better name :))
function Invoke-OnPowerShell5OrLaterOnly ([ScriptBlock]$ScriptBlock) {
  if ($PSVersionTable.PsVersion.Major -ge 5) {
    & $ScriptBlock
  }
}