Clean up & simplify error handling and reporting

Scripts/Features/Invoke-Changes.ps1

@@ -272,7 +272,6 @@ function Invoke-ApplyFeatures {
         }
 
         if (-not (Invoke-FeatureApply -FeatureId $featureId)) {
-            $script:ApplyFeatureFailures++
             $script:FeatureFailures++
         }
         Write-Host ""
@@ -315,7 +314,6 @@ function Invoke-UndoFeatures {
         }
 
         if (-not (Invoke-FeatureUndo -FeatureId $featureId)) {
-            $script:UndoFeatureFailures++
             $script:FeatureFailures++
         }
         Write-Host ""
@@ -349,9 +347,6 @@ function Invoke-AllChanges {
 
     $script:AppRemovalFailures = 0
     $script:FeatureFailures = 0
-    $script:ApplyFeatureFailures = 0
-    $script:UndoFeatureFailures = 0
-    $script:PrerequisiteFailures = 0
     $script:AppRemovalVerificationUnavailable = $false
 
     # ---- Gather work items ----
@@ -434,7 +429,7 @@ function Invoke-AllChanges {
             $restorePointSucceeded = Invoke-SystemRestorePoint
             if (-not $restorePointSucceeded) {
                 if ($script:CancelRequested) { return }
-                $script:PrerequisiteFailures++
+                $script:FeatureFailures++
             }
             Write-Host ""
         }
@@ -466,19 +461,9 @@ function Invoke-AllChanges {
         Write-Warning "$($script:AppRemovalFailures) app removal(s) failed. See output above for details."
     }
 
-    if ($script:ApplyFeatureFailures -gt 0) {
+    if ($script:FeatureFailures -gt 0) {
         Write-Host ""
-        Write-Warning "$($script:ApplyFeatureFailures) feature change(s) failed to apply. See output above for details."
-    }
-
-    if ($script:UndoFeatureFailures -gt 0) {
-        Write-Host ""
-        Write-Warning "$($script:UndoFeatureFailures) feature change(s) failed to undo. See output above for details."
-    }
-
-    if ($script:PrerequisiteFailures -gt 0) {
-        Write-Host ""
-        Write-Warning "$($script:PrerequisiteFailures) requested prerequisite(s) could not be completed. Changes continued at your request."
+        Write-Warning "$($script:FeatureFailures) feature change(s) failed. See output above for details."
     }
 
     if ($script:AppRemovalVerificationUnavailable) {

Scripts/GUI/Show-ApplyModal.ps1

@@ -114,13 +114,7 @@ function Show-ApplyModal {
         try {
             Invoke-AllChanges
 
-            $appRemovalFailureCount = [int]$script:AppRemovalFailures
-            $applyFailureCount = [int]$script:ApplyFeatureFailures
-            $undoFailureCount = [int]$script:UndoFeatureFailures
-            $featureFailureCount = $applyFailureCount + $undoFailureCount
-            $prerequisiteFailureCount = [int]$script:PrerequisiteFailures
-            # App removals are a subset of failed features, so adding both counters
-            # would report each affected feature twice.
+            $featureFailureCount = [int]$script:FeatureFailures
             $failureCount = $featureFailureCount
             $appRemovalVerificationUnavailable = [bool]$script:AppRemovalVerificationUnavailable
             
@@ -149,7 +143,7 @@ function Show-ApplyModal {
                 $script:ApplyCompletionIconEl.Foreground = [System.Windows.Media.SolidColorBrush]::new([System.Windows.Media.ColorConverter]::ConvertFromString("#e8912d"))
                 $script:ApplyCompletionTitleEl.Text = "Cancelled"
                 $script:ApplyCompletionMessageEl.Text = "Script execution was cancelled by the user."
-            } elseif ($failureCount -gt 0 -or $prerequisiteFailureCount -gt 0 -or $appRemovalVerificationUnavailable) {
+            } elseif ($failureCount -gt 0 -or $appRemovalVerificationUnavailable) {
                 if ($failureCount -gt 0) {
                     Write-Host "Script completed with $failureCount error(s)."
                 }
@@ -162,13 +156,7 @@ function Show-ApplyModal {
                 }
                 else {
                     $script:ApplyCompletionTitleEl.Text = "Changes Applied with Errors"
-                    $failureMessages = @()
-                    if ($appRemovalFailureCount -gt 0) { $failureMessages += "$appRemovalFailureCount app removal(s) failed" }
-                    if ($applyFailureCount -gt 0) { $failureMessages += "$applyFailureCount feature change(s) failed to apply" }
-                    if ($undoFailureCount -gt 0) { $failureMessages += "$undoFailureCount feature change(s) failed to undo" }
-                    if ($prerequisiteFailureCount -gt 0) { $failureMessages += "$prerequisiteFailureCount requested prerequisite(s) could not be completed" }
-                    if ($appRemovalVerificationUnavailable) { $failureMessages += "Unable to verify if all apps were uninstalled successfully" }
-                    $script:ApplyCompletionMessageEl.Text = "$($failureMessages -join '; '). See console for details."
+                    $script:ApplyCompletionMessageEl.Text = "$featureFailureCount change(s) failed. See console for details."
                 }
             } else {
                 Write-Host "All changes have been applied successfully!"

Tests/Invoke-Changes.Tests.ps1

@@ -263,7 +263,6 @@ Describe 'Invoke-ApplyFeatures' {
 
     It 'counts a failed feature application and continues with later features' {
         $script:FeatureFailures = 0
-        $script:ApplyFeatureFailures = 0
         Mock Invoke-FeatureApply {
             param($FeatureId)
             return ($FeatureId -ne 'One')
@@ -272,7 +271,6 @@ Describe 'Invoke-ApplyFeatures' {
         Invoke-ApplyFeatures -FeatureIds @('One', 'Two') -StartStep 1 -TotalSteps 2
 
         $script:FeatureFailures | Should -Be 1
-        $script:ApplyFeatureFailures | Should -Be 1
         Should -Invoke Invoke-FeatureApply -Times 2 -Exactly
     }
 }
@@ -305,13 +303,11 @@ Describe 'Invoke-UndoFeatures' {
 
     It 'counts one failure when a feature undo fails' {
         $script:FeatureFailures = 0
-        $script:UndoFeatureFailures = 0
         Mock Invoke-FeatureUndo { $false }
 
         Invoke-UndoFeatures -FeatureIds @('RegistryUndo') -StartStep 1 -TotalSteps 1
 
         $script:FeatureFailures | Should -Be 1
-        $script:UndoFeatureFailures | Should -Be 1
         Should -Invoke Invoke-FeatureUndo -Times 1 -Exactly
     }
 
@@ -484,15 +480,15 @@ Describe 'Invoke-AllChanges' {
         $script:order | Should -Be @('restore-point', 'apply')
     }
 
-    It 'reports a restore point failure when the user chooses to continue' {
+    It 'counts a restore point failure as a feature failure when the user chooses to continue' {
         $script:Params = @{ CreateRestorePoint = $true; CustomApply = $true }
         $script:UndoParams = @{}
         Mock Invoke-SystemRestorePoint { $false }
 
         Invoke-AllChanges
 
-        $script:PrerequisiteFailures | Should -Be 1
-        Should -Invoke Write-Warning -Times 1 -Exactly -ParameterFilter { $Message -match 'requested prerequisite' }
+        $script:FeatureFailures | Should -Be 1
+        Should -Invoke Write-Warning -Times 1 -Exactly -ParameterFilter { $Message -match '1 feature change\(s\) failed\.' }
     }
 
     It 'reports app removal failures after all requested work completes' {