fix: read and write from registry

.github/workflows/pull.yml

@@ -0,0 +1,54 @@
+name: install.pull
+
+on:
+  pull_request:
+    types:
+      - opened
+      - edited
+      - reopened
+      - synchronize
+
+concurrency: 
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+
+jobs:
+  pull_install:
+    runs-on: windows-latest
+    defaults:
+      run:
+        shell: pwsh
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Context
+        run: |
+          $PSVersionTable
+          Get-Module -ListAvailable Pester | Sort-Object Version -Descending | Select-Object -First 1 | Format-List Name,Version,Path
+
+      - name: Test
+        env:
+          RUN_DESTRUCTIVE_TESTS: '1'
+        run: |
+          Import-Module Pester -MinimumVersion '5.0.0' -Force
+          New-Item -ItemType Directory -Force -Path TestResults | Out-Null
+
+          $config = [PesterConfiguration]::Default
+          $config.Run.Path = @('tests')       # or '.' if your tests stay at repo root
+          $config.Output.Verbosity = 'Normal'
+          $config.TestResult.Enabled = $true
+          $config.TestResult.OutputPath = 'TestResults/Pester-safe.xml'
+          $config.TestResult.OutputFormat = 'NUnitXml'
+
+          Invoke-Pester -Configuration $config
+
+      - name: Publish Results
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: pester-safe-results
+          path: TestResults/Pester-safe.xml

README.md

@@ -78,6 +78,34 @@ Usage:
 ...
 ```
 
+## Tests
+
+### Windows
+
+We use [Pester](https://pester.dev/) to test the installation script. We develop
+using Azure VM running Windows where there is an older version of Pester baked
+in to the image (v3.4).
+
+To ensure tests use Pester v5, configure your `$PROFILE`:
+
+```powershell
+# Clean out legacy module roots (prevents Pester 3.4 autoload)
+$paths = $env:PSModulePath -split ';' | Where-Object {
+    $_ -notlike '*WindowsPowerShell*' -and $_ -notlike '*v1.0*'
+}
+$env:PSModulePath = ($paths -join ';')
+
+# Force Pester 5
+Remove-Module Pester -ErrorAction SilentlyContinue
+Import-Module "$HOME\Documents\PowerShell\Modules\Pester\5.7.1\Pester.psd1" -Force
+```
+
+To run the tests use:
+
+```powershell
+Invoke-Pester -CI
+```
+
 ## Requirements
 
 - **macOS/Linux:** `curl`, `bash`

install.ps1

@@ -1,7 +1,7 @@
 <#
 Usage:
-  .\install.ps1            → Install the Pair CLI
-  .\install.ps1 -Uninstall → Uninstall the Pair CLI
+  .\install.ps1            → Install the PairSpaces CLI
+  .\install.ps1 -Uninstall → Uninstall the PairSpaces CLI
 #>
 
 $ErrorActionPreference = "Stop"
@@ -14,7 +14,7 @@ $name       = "pair"
 $binary     = "$name.exe"
 $envName    = "latest"
 $baseUrl    = "https://downloads.pairspaces.com/$envName"
-$installDir = "$env:USERPROFILE\AppData\Local\$name"
+$installDir = Join-Path $env:LOCALAPPDATA $name
 $destBin    = "$installDir\$binary"
 
 # =============================================================================
@@ -85,14 +85,41 @@ function Make-Executable {
 }
 
 function Ensure-InPath {
-    $currentPath = [System.Environment]::GetEnvironmentVariable("Path", "User")
-    if (-not ($currentPath.Split(';') -contains $installDir)) {
+    # Open HKCU:\Environment and get the raw, non-expanded Path
+    $reg = [Microsoft.Win32.Registry]::CurrentUser.OpenSubKey("Environment", $true)
+    if (-not $reg) { Show-Error "Could not open HKCU:\Environment for write." }
+
+    $rawPath = $reg.GetValue(
+        "Path", "",
+        [Microsoft.Win32.RegistryValueOptions]::DoNotExpandEnvironmentNames
+    )
+
+    $segments = @()
+    if ($rawPath) {
+        $segments = $rawPath -split ';' | Where-Object { $_ -and $_.Trim() -ne '' }
+    }
+
+    $expandedInstall = [Environment]::ExpandEnvironmentVariables($installDir).TrimEnd('\')
+    # Avoid duplicates by comparing expanded values of each segment
+    $alreadyPresent = $false
+    foreach ($seg in $segments) {
+        $expandedSeg = [Environment]::ExpandEnvironmentVariables($seg).TrimEnd('\')
+        if ([string]::Compare($expandedSeg, $expandedInstall, $true) -eq 0) {
+            $alreadyPresent = $true
+            break
+        }
+    }
+
+    if (-not $alreadyPresent) {
         Show-Title "Adding to PATH" $installDir
-        $currentPath = $currentPath.TrimEnd(';')
-        $newPath = "$currentPath;$installDir"
-        [System.Environment]::SetEnvironmentVariable("Path", $newPath, "User")
+        $newRaw = ($segments + $installDir) -join ';'
+        # Write back as REG_EXPAND_SZ to preserve any %VARS% that may be present
+        $reg.SetValue("Path", $newRaw, [Microsoft.Win32.RegistryValueKind]::ExpandString)
+        Refresh-Environment
         Write-Host (" You may need to restart your terminal to use '${binary}'") -ForegroundColor Yellow
     }
+
+    $reg.Close()
 }
 
 # =============================================================================
@@ -114,13 +141,35 @@ function Uninstall-App {
         Info "Removed directory $installDir"
     }
 
-    # Remove from PATH
-    $currentPath = [System.Environment]::GetEnvironmentVariable("Path", "User")
-    if ($currentPath.Split(';') -contains $installDir) {
-        $newPath = ($currentPath.Split(';') | Where-Object { $_ -ne $installDir }) -join ';'
-        [System.Environment]::SetEnvironmentVariable("Path", $newPath, "User")
-        Info "Removed $installDir from user PATH"
-        Write-Host (" You may need to restart your shell for changes to take effect.") -ForegroundColor Yellow
+    # Remove from PATH (preserves REG_EXPAND_SZ and respects %VARS%)
+    try {
+        $reg = [Microsoft.Win32.Registry]::CurrentUser.OpenSubKey("Environment", $true)
+        if ($reg) {
+            $rawPath = $reg.GetValue("Path", "", [Microsoft.Win32.RegistryValueOptions]::DoNotExpandEnvironmentNames)
+
+            if ($rawPath) {
+                $expandedInstall = [Environment]::ExpandEnvironmentVariables($installDir).TrimEnd('\')
+
+                $newSegs = @()
+                foreach ($seg in ($rawPath -split ';')) {
+                    if (-not $seg) { continue }
+                    $expandedSeg = [Environment]::ExpandEnvironmentVariables($seg).TrimEnd('\')
+                    if ([string]::Compare($expandedSeg, $expandedInstall, $true) -ne 0) {
+                        $newSegs += $seg
+                    }
+                }
+
+                $reg.SetValue("Path", ($newSegs -join ';'), [Microsoft.Win32.RegistryValueKind]::ExpandString)
+                Info "Removed $installDir from user PATH"
+                Refresh-Environment
+                Write-Host (" You may need to restart your shell for changes to take effect.") -ForegroundColor Yellow
+            }
+        } else {
+            Info "Could not open HKCU:\Environment to remove from PATH"
+        }
+        $reg.Close()
+    } catch {
+        Info "Failed to update PATH during uninstall: $($_.Exception.Message)"
     }
 
     # Remove directory
@@ -131,7 +180,33 @@ function Uninstall-App {
     }
 
     Show-Title "Uninstallation Complete"
-    exit 0
+}
+
+# =============================================================================
+# Refresh Environment
+# =============================================================================
+
+function Refresh-Environment {
+    # Broadcast WM_SETTINGCHANGE "Environment" so new processes see updates immediately
+    $cs = @"
+using System;
+using System.Runtime.InteropServices;
+public static class NativeMethods {
+  public const int HWND_BROADCAST = 0xffff;
+  public const int WM_SETTINGCHANGE = 0x1A;
+  public const int SMTO_ABORTIFHUNG = 0x0002;
+
+  [DllImport("user32.dll", SetLastError=true, CharSet=CharSet.Auto)]
+  public static extern IntPtr SendMessageTimeout(
+      IntPtr hWnd, int Msg, IntPtr wParam, string lParam,
+      int fuFlags, int uTimeout, out IntPtr lpdwResult);
+}
+"@
+    Add-Type -TypeDefinition $cs -ErrorAction SilentlyContinue | Out-Null
+    [IntPtr]$out = [IntPtr]::Zero
+    [void][NativeMethods]::SendMessageTimeout(
+        [IntPtr]0xffff, 0x1A, [IntPtr]::Zero, "Environment",
+        0x0002, 5000, [ref]$out)
 }
 
 # =============================================================================
@@ -167,4 +242,6 @@ function Main {
     Write-Host (" Restart your shell and run '${binary} help' to get started.") -ForegroundColor Green
 }
 
-Main @args
+if ($MyInvocation.InvocationName -ne '.') {
+    Main @args
+}