Pester - Script variables should reset for every describe

1.WhatIHaveToDo.ps1

Describe "When installing packages from a packages.config manifest" {
  $script:chocolatey_nuget_was_called = $false  
  $script:chocolatey_rubygem_was_called = $false
  $script:chocolatey_webpi_was_called = $false
  $script:packageName = ''
  $script:version = ''

# content here
}

Describe "When installing packages from a packages.config manifest that doesn't exist" {
  $script:chocolatey_nuget_was_called = $false  
  $script:chocolatey_rubygem_was_called = $false
  $script:chocolatey_webpi_was_called = $false
  $script:packageName = ''
  $script:version = ''

# content here

}

2.WhatIWantToDo.ps1

#all script variables automatically reset
#$script:chocolatey_nuget_was_called = $false  
#$script:chocolatey_rubygem_was_called = $false
#$script:chocolatey_webpi_was_called = $false
#$script:packageName = ''
#$script:version = ''

Describe "When installing packages from a packages.config manifest" {
# content here
}

Describe "When installing packages from a packages.config manifest that doesn't exist" {
# content here
}

3.Workaround.ps1

function Initialize-Variables {
 $script:chocolatey_nuget_was_called = $false  
  $script:chocolatey_rubygem_was_called = $false
  $script:chocolatey_webpi_was_called = $false
  $script:packageName = ''
  $script:version = ''
}

Describe "When installing packages from a packages.config manifest" {
  Initialize-Variables
# content here
}

Describe "When installing packages from a packages.config manifest that doesn't exist" {
  Initialize-Variables
# content here
}