Added unit tests

powershell_tests/setup.Tests.ps1

@@ -0,0 +1,151 @@
+# Ensure the latest version of Pester is installed and imported
+if (-not (Get-Module -ListAvailable -Name Pester | Where-Object { $_.Version -ge [version]"5.3.1" })) {
+  Install-Module -Name Pester -Force -Scope CurrentUser -SkipPublisherCheck
+}
+
+Import-Module -Name Pester -MinimumVersion 5.3.1
+
+# Describe block to contain all tests and setup
+Describe "Setup and Tests" {
+
+  BeforeAll {
+    # Construct the absolute path to setup.ps1
+    $setupScriptPath = Join-Path -Path (Get-Location) -ChildPath "setup.ps1"
+
+    # Check if the setup script exists
+    if (-Not (Test-Path -Path $setupScriptPath)) {
+      Write-Host "Error: setup.ps1 script not found at path: $setupScriptPath"
+      exit 1
+    }
+
+    # Load the script to test
+    . $setupScriptPath
+  }
+
+  Context "Write-Log Tests" -Tag "Unit" {
+    It "should write INFO level log" {
+      $logFilePath = Join-Path $env:TEMP "script_log.txt"
+      Remove-Item $logFilePath -ErrorAction SilentlyContinue
+
+      Write-Log -Message "Test Info Message" -Level "INFO"
+
+      $logContent = Get-Content $logFilePath
+      $logContent | Should -Contain "INFO: Test Info Message"
+    }
+
+    It "should write ERROR level log" {
+      $logFilePath = Join-Path $env:TEMP "script_log.txt"
+      Remove-Item $logFilePath -ErrorAction SilentlyContinue
+
+      Write-Log -Message "Test Error Message" -Level "ERROR"
+
+      $logContent = Get-Content $logFilePath
+      $logContent | Should -Contain "ERROR: Test Error Message"
+    }
+  }
+
+  Context "Get-UserSelection Tests" -Tag "Unit" {
+    It "should handle valid input correctly" {
+      Mock Read-Host { return "A,B,C" }
+    
+      $options = @("Option1", "Option2", "Option3")
+      $indices = Get-UserSelection -prompt "Select options" -options $options -defaultChoice "A"
+    
+      $indices | Should -Be @(0, 1, 2)
+    }
+
+    It "should return indices for selected options" {
+      Mock Read-Host { return "a,b" }
+        
+      $options = @("Option1", "Option2", "Option3")
+      $indices = Get-UserSelection -prompt "Select options" -options $options
+
+      $indices | Should -Be @(0, 1)
+    }
+
+    It "should return default choice if no input" {
+      Mock Read-Host { return "" }
+
+      $options = @("Option1", "Option2", "Option3")
+      $indices = Get-UserSelection -prompt "Select options" -options $options -defaultChoice "C"
+
+      $indices | Should -Be @(2)
+    }
+
+    It "should handle mixed valid and invalid input correctly" {
+      Mock Read-Host { return "A,X,B,Y,C,Z" }
+    
+      $options = @("Option1", "Option2", "Option3")
+      $indices = Get-UserSelection -prompt "Select options" -options $options -defaultChoice "A"
+    
+      $indices | Should -Be @(0, 1, 2)
+    }
+
+    It "should handle invalid input gracefully" {
+      Mock Read-Host { return "x,y,z" }
+    
+      $options = @("Option1", "Option2", "Option3")
+      $indices = Get-UserSelection -prompt "Select options" -options $options -defaultChoice "A"
+    
+      $indices | Should -Be @()
+    }
+    
+    It "should handle input without whitespace" {
+      Mock Read-Host { return "a,b,c" }
+
+      $options = @("Option1", "Option2", "Option3")
+      $indices = Get-UserSelection -prompt "Select options" -options $options
+
+      $indices | Should -Be @(0, 1, 2)
+    }
+  }
+
+  Context "Exit-Script Tests" -Tag "Unit" {
+    BeforeAll {
+      # Set environment variables for the test
+      $global:OldVirtualPath = "C:\old\path"
+      $global:LogFilePath = "C:\path\to\logfile.log"
+    }
+  
+    BeforeEach {
+      Mock Write-Log {}
+      Mock Start-Process {}
+      Mock Read-Host { return "Y" }
+
+      # Backup the original PATH
+      $global:OriginalPath = $env:PATH
+    }
+  
+    AfterEach {
+      # Restore the original PATH
+      $env:PATH = $OriginalPath
+    }
+  
+    It "should exit with the given exit code without waiting for key press" {
+      $exitCode = Exit-Script -exitCode 0 -isSubShell $true -waitForKeypress $false
+      $exitCode | Should -Be 0
+    }
+    
+    It "should prompt to open log file on error" {
+      Exit-Script -exitCode 1 -isSubShell $true -waitForKeypress $false
+      Assert-MockCalled Read-Host -Exactly 1
+      Assert-MockCalled Start-Process -Exactly 1
+    }
+  
+    It "should restore the environment path if OldVirtualPath is set" {
+      # Set a different PATH to simulate the change
+      $env:PATH = "C:\new\path"
+      Exit-Script -exitCode 0 -isSubShell $true -waitForKeypress $false
+      $env:PATH | Should -Be "C:\old\path"
+    }
+  }
+
+  Context "Get-PythonVersionTag Tests" -Tag "Unit" {
+    It "should return the correct Python version tag" {
+      Mock Invoke-Expression { param($cmd) return "cp39-win_amd64" }
+
+      $tag = Get-PythonVersionTag
+      $tag | Should -Be "cp39-win_amd64"
+    }
+  }
+}