Fixed a NullReferenceException when starting application with empty shell on Windows

[Shalini-Ashokan]

Note

Are you waiting for the changes in this PR to be merged?
It would be very helpful if you could test the resulting artifacts from this PR and let us know in a comment if this change resolves your issue. Thank you!

Issue Details

A NullReferenceException is thrown when starting the application with an empty shell on Windows.

Root Cause

The shell does not have any items, so the shell item is null. In the source code, a null check was not implemented.

Description of Change

Throws an InvalidOperationException when the Shell item or the current Shell item is null.

Reference

Ensured consistent behavior with Android by referring to the following code.

maui/src/Controls/src/Core/Compatibility/Handlers/Shell/Android/ShellItemRenderer.cs

Line 79 in 6ff7573

if (ShellItem is null)

Validated the behavior in the following platforms

• Android
• Windows
• iOS
• Mac

Issues Fixed

Fixes #21562
Fixes #10041

Output ScreenShot

Before	After
BeforeFix.3.mp4	After-Fix-1.mp4

[dotnet-policy-service]

Hey there @@Shalini-Ashokan! Thank you so much for your PR! Someone from the team will get assigned to your PR shortly and we'll get it reviewed.

[jsuarezruiz]

What's the behavior on other platforms? Would be nice to align the behavior and throw the same exception with the same message if possible.

[Shalini-Ashokan]

@jsuarezruiz, On Android, the empty Shell throws a similar exception.

[jsuarezruiz]

/azp run MAUI-UITests-public

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

The base branch was changed.

[PureWeen]

pausing for a second to review this one

[mattleibow]

The fact that this PR is for windows and this other one is for mac and ios: #29464

this means only android throws. Maybe android is wrong.

[mattleibow]

This is what android does, for future me

maui/src/Controls/src/Core/Compatibility/Handlers/Shell/Android/ShellItemRenderer.cs

Lines 79 to 83 in 6262d96

	if (ShellItem is null)
	throw new InvalidOperationException("Active Shell Item not set. Have you added any Shell Items to your Shell?");
	if (ShellItem.CurrentItem is null)
	throw new InvalidOperationException($"Content not found for active {ShellItem}. Title: {ShellItem.Title}. Route: {ShellItem.Route}.");

[mattleibow]

This needs the test to be shared. Probably worth merging with #29464

[Shalini-Ashokan]

@mattleibow, The changes from PR #29464 have been moved to this PR.

[kubaflo]

Could you please review the AI's summary?

[Shalini-Ashokan]

I addressed the ai concerns.

@kubaflo, I addressed the AI concerns.

[kubaflo]

/review -b feature/refactor-copilot-yml

[MauiBot]

🤖 Automated review — alternative fix proposed

The expert-reviewer evaluation compared the PR fix against #1 automatically generated candidates and selected try-fix-1 as the strongest fix.

Why: try-fix-1 wins because it passed the requested Android Shell regression run, while the PR and pr-plus-reviewer inherited the failed gate result. Among passing candidates, it validates the normal Windows CurrentItem mapper path more completely than try-fix-3.

Please consider applying the candidate diff below (or use it as guidance). Once you push an update, this workflow will re-trigger and re-evaluate.

Candidate diff (`try-fix-1`)

diff --git a/src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/ShellRenderer.cs b/src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/ShellRenderer.cs
index 4568795b1f..ba0e1c75e0 100644
--- a/src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/ShellRenderer.cs
+++ b/src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/ShellRenderer.cs
@@ -364,7 +364,11 @@ namespace Microsoft.Maui.Controls.Handlers.Compatibility
 		{
 			if (Shell.CurrentItem == null)
 			{
-				return;
+				throw new InvalidOperationException("Active Shell Item not set. Have you added any Shell Items to your Shell?");
+			}
+			else if (Shell.CurrentItem.CurrentItem == null)
+			{
+				throw new InvalidOperationException($"Content not found for active {Shell.CurrentItem}. Title: {Shell.CurrentItem.Title}. Route: {Shell.CurrentItem.Route}.");
 			}
 			else if (_currentShellItemRenderer == null)
 			{
diff --git a/src/Controls/src/Core/Handlers/Shell/ShellHandler.Windows.cs b/src/Controls/src/Core/Handlers/Shell/ShellHandler.Windows.cs
index a1308c79b9..a8b406ff8b 100644
--- a/src/Controls/src/Core/Handlers/Shell/ShellHandler.Windows.cs
+++ b/src/Controls/src/Core/Handlers/Shell/ShellHandler.Windows.cs
@@ -119,7 +119,15 @@ namespace Microsoft.Maui.Controls.Handlers
 
 		public static void MapCurrentItem(ShellHandler handler, Shell view)
 		{
-			handler.PlatformView.SwitchShellItem(view.CurrentItem, true);
+			var currentItem = view.CurrentItem;
+
+			if (currentItem is null)
+				throw new InvalidOperationException("Active Shell Item not set. Have you added any Shell Items to your Shell?");
+
+			if (currentItem.CurrentItem is null)
+				throw new InvalidOperationException($"Content not found for active {currentItem}. Title: {currentItem.Title}. Route: {currentItem.Route}.");
+
+			handler.PlatformView.SwitchShellItem(currentItem, true);
 		}
 
 		public static void MapFlyoutBackground(ShellHandler handler, Shell view)
diff --git a/src/Controls/tests/DeviceTests/Elements/Shell/ShellTests.cs b/src/Controls/tests/DeviceTests/Elements/Shell/ShellTests.cs
index 9b2c887e8a..020969604c 100644
--- a/src/Controls/tests/DeviceTests/Elements/Shell/ShellTests.cs
+++ b/src/Controls/tests/DeviceTests/Elements/Shell/ShellTests.cs
@@ -1139,6 +1139,23 @@ namespace Microsoft.Maui.DeviceTests
 			});
 		}
 
+#if !ANDROID // On Android, the exception causes the app to terminate, resulting in a device test failure.
+		[Fact(DisplayName = "Initialize Empty Shell Throws InvalidOperationException")]
+		public async Task InitializeEmptyShellThrowsInvalidOperationException()
+		{
+			SetupBuilder();
+			var shell = new Shell();
+
+			await Assert.ThrowsAsync<InvalidOperationException>(async () =>
+			{
+				await CreateHandlerAndAddToWindow<ShellHandler>(shell, (handler) =>
+				{
+					return Task.CompletedTask;
+				});
+			});
+		}
+#endif
+
 		protected Task<Shell> CreateShellAsync(Action<Shell> action) =>
 			InvokeOnMainThreadAsync(() =>
 			{

[kubaflo]

Could you please check the ai's suggestions?

[Shalini-Ashokan]

🤖 Automated review — alternative fix proposed

The expert-reviewer evaluation compared the PR fix against #1 automatically generated candidates and selected try-fix-1 as the strongest fix.

Why: try-fix-1 wins because it passed the requested Android Shell regression run, while the PR and pr-plus-reviewer inherited the failed gate result. Among passing candidates, it validates the normal Windows CurrentItem mapper path more completely than try-fix-3.

Please consider applying the candidate diff below (or use it as guidance). Once you push an update, this workflow will re-trigger and re-evaluate.

Candidate diff (try-fix-1)

The null checks are already in SwitchShellItem, which is called by MapCurrentItem, so this path is already protected and moving the checks to MapCurrentItem is unnecessary.

[kubaflo]

/review -b feature/refactor-copilot-yml -p windows

[MauiBot]

🤖 AI Summary

👋 @Shalini-Ashokan — new AI review results are available. Please review the latest session below.

📊 Review Session — 6385aca · Addressed the AI concern · 2026-05-26 23:45 UTC

🚦 Gate — Test Before & After Fix

Gate Result: ❌ FAILED

Platform: WINDOWS · Base: main · Merge base: b0ea772f

🩺 Fix does not pass the tests — every test still fails after applying the fix. The PR's change does not resolve the failure(s).

Test	Without Fix (expect FAIL)	With Fix (expect PASS)
📱 ShellTests (InitializeEmptyShellThrowsInvalidOperationException) Category=Shell	✅ FAIL — 342s	❌ FAIL — 158s

🔴 Without fix — 📱 ShellTests (InitializeEmptyShellThrowsInvalidOperationException): FAIL ✅ · 342s

  Determining projects to restore...
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  ##vso[build.updatebuildnumber]10.0.80-ci+azdo.14198705
  Graphics -> D:\a\1\s\artifacts\bin\Graphics\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Graphics.dll
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  Graphics.Win2D -> D:\a\1\s\artifacts\bin\Graphics.Win2D\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Graphics.Win2D.WinUI.Desktop.dll
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  Controls.BindingSourceGen -> D:\a\1\s\artifacts\bin\Controls.BindingSourceGen\Release\netstandard2.0\Microsoft.Maui.Controls.BindingSourceGen.dll
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  Controls.Xaml -> D:\a\1\s\artifacts\bin\Controls.Xaml\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Controls.Xaml.dll
  TestUtils.DeviceTests -> D:\a\1\s\artifacts\bin\TestUtils.DeviceTests\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.TestUtils.DeviceTests.dll
  TestUtils.DeviceTests.Runners -> D:\a\1\s\artifacts\bin\TestUtils.DeviceTests.Runners\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.TestUtils.DeviceTests.Runners.dll
  Core.DeviceTests.Shared -> D:\a\1\s\artifacts\bin\Core.DeviceTests.Shared\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.DeviceTests.Shared.dll
  Maps -> D:\a\1\s\artifacts\bin\Maps\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Maps.dll
  ##vso[build.updatebuildnumber]10.0.80-ci+azdo.14198705
  Controls.Maps -> D:\a\1\s\artifacts\bin\Controls.Maps\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Controls.Maps.dll
  TestUtils.DeviceTests.Runners.SourceGen -> D:\a\1\s\artifacts\bin\TestUtils.DeviceTests.Runners.SourceGen\Release\netstandard2.0\Microsoft.Maui.TestUtils.DeviceTests.Runners.SourceGen.dll
  ##vso[build.updatebuildnumber]10.0.80-ci+azdo.14198705
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  Graphics -> D:\a\1\s\artifacts\bin\Graphics\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Graphics.dll
  Controls.DeviceTests -> D:\a\1\s\artifacts\bin\Controls.DeviceTests\Release\net10.0-windows10.0.19041.0\win-x64\Microsoft.Maui.Controls.DeviceTests.dll

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:04:59.12
Test run for D:\a\1\s\artifacts\bin\Controls.DeviceTests\Release\net10.0-windows10.0.19041.0\win-x64\Microsoft.Maui.Controls.DeviceTests.dll (.NETCoreApp,Version=v10.0)
VSTest version 18.0.1 (x64)

Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Testhost process for source(s) 'D:\a\1\s\artifacts\bin\Controls.DeviceTests\Release\net10.0-windows10.0.19041.0\win-x64\Microsoft.Maui.Controls.DeviceTests.dll' exited with error: Unhandled exception. System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.TestPlatform.CoreUtilities, Version=15.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. The system cannot find the file specified.
File name: 'Microsoft.TestPlatform.CoreUtilities, Version=15.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at Microsoft.VisualStudio.TestPlatform.TestHost.Program.Main(String[] args) in /_/src/vstest/src/testhost.x86/Program.cs:line 41
. Please check the diagnostic logs for more information.
Results File: D:\a\1\s\artifacts\log\TestResults.trx

Test Run Aborted.
  Tests completed with exit code: 1

🟢 With fix — 📱 ShellTests (InitializeEmptyShellThrowsInvalidOperationException): FAIL ❌ · 158s

  Determining projects to restore...
  All projects are up-to-date for restore.
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  Controls.Core -> D:\a\1\s\artifacts\bin\Controls.Core\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Controls.dll
  Maps -> D:\a\1\s\artifacts\bin\Maps\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Maps.dll
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  Controls.Maps -> D:\a\1\s\artifacts\bin\Controls.Maps\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Controls.Maps.dll
  TestUtils.DeviceTests.Runners -> D:\a\1\s\artifacts\bin\TestUtils.DeviceTests.Runners\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.TestUtils.DeviceTests.Runners.dll
  Core.DeviceTests.Shared -> D:\a\1\s\artifacts\bin\Core.DeviceTests.Shared\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.DeviceTests.Shared.dll
  TestUtils.DeviceTests.Runners.SourceGen -> D:\a\1\s\artifacts\bin\TestUtils.DeviceTests.Runners.SourceGen\Release\netstandard2.0\Microsoft.Maui.TestUtils.DeviceTests.Runners.SourceGen.dll
  ##vso[build.updatebuildnumber]10.0.80-ci+azdo.14198705
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  Graphics -> D:\a\1\s\artifacts\bin\Graphics\Release\net10.0-windows10.0.19041.0\Microsoft.Maui.Graphics.dll
  Controls.DeviceTests -> D:\a\1\s\artifacts\bin\Controls.DeviceTests\Release\net10.0-windows10.0.19041.0\win-x64\Microsoft.Maui.Controls.DeviceTests.dll

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:02:26.08
Test run for D:\a\1\s\artifacts\bin\Controls.DeviceTests\Release\net10.0-windows10.0.19041.0\win-x64\Microsoft.Maui.Controls.DeviceTests.dll (.NETCoreApp,Version=v10.0)
VSTest version 18.0.1 (x64)

Starting test execution, please wait...
A total of 1 test files matched the specified pattern.
Testhost process for source(s) 'D:\a\1\s\artifacts\bin\Controls.DeviceTests\Release\net10.0-windows10.0.19041.0\win-x64\Microsoft.Maui.Controls.DeviceTests.dll' exited with error: Unhandled exception. System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.TestPlatform.CoreUtilities, Version=15.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. The system cannot find the file specified.
File name: 'Microsoft.TestPlatform.CoreUtilities, Version=15.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at Microsoft.VisualStudio.TestPlatform.TestHost.Program.Main(String[] args) in /_/src/vstest/src/testhost.x86/Program.cs:line 41
. Please check the diagnostic logs for more information.
WARNING: Overwriting results file: D:\a\1\s\artifacts\log\TestResults.trx
Results File: D:\a\1\s\artifacts\log\TestResults.trx

Test Run Aborted.
  Tests completed with exit code: 1

⚠️ Failure Details

• ❌ ShellTests (InitializeEmptyShellThrowsInvalidOperationException) FAILED with fix (should pass)

📁 Fix files reverted (3 files)

• eng/pipelines/ci-copilot.yml
• src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/ShellRenderer.cs
• src/Controls/src/Core/Handlers/Shell/Windows/ShellView.cs

---

🧪 UI Tests — Shell

Detected UI test categories: Shell

✅ Deep UI tests — 266 passed, 0 failed across 1 category on platform-pool agent (replaces in-process counts above).

🧪 UI Test Execution Results (deep, platform pool)

Category	Tests	Snapshot diffs
Shell	266/266 ✓	—
📎 Download drop-deep-uitests artifact (TRX + snapshot diffs)

---

🔍 Regression Cross-Reference

🔍 Regression Cross-Reference

🟢 No regression risks detected. No labeled bug-fix PRs in the last 6 months touched the modified files.

---

🔍 Pre-Flight — Context & Validation

Issue: #21562 - NullReferenceException when starting application with empty shell on Windows; #10041 - Shell FlyoutContent CollectionView Windows unhandled exception
PR: #28879 - Fixed a NullReferenceException when starting application with empty shell on Windows
Platforms Affected: Windows primarily; PR also touches iOS/MacCatalyst compatibility Shell renderer for behavior alignment
Files Changed: 2 implementation, 1 test

Key Findings

• Empty Shell on Windows currently flows Shell.CurrentItem == null into ShellView.SwitchShellItem, where Routing.IsImplicit(newItem) dereferences null and throws an unclear NullReferenceException.
• PR's fix adds explicit InvalidOperationException guards in Windows ShellView.SwitchShellItem and iOS ShellRenderer.SetupCurrentShellItem, plus a shared Controls device test excluded on Android.
• Gate already failed for environmental/testhost reasons: both without-fix and with-fix Windows device-test runs aborted with missing Microsoft.TestPlatform.CoreUtilities; do not treat that as functional evidence for or against any candidate.
• Review discussion asked for cross-platform alignment of the exception behavior and message; PR now includes matching Windows/iOS messages.

Code Review Summary

Verdict: LGTM
Confidence: high
Errors: 0 | Warnings: 0 | Suggestions: 0

Key code review findings:

• None. Code-review sub-agent found the PR small, consistent, and well-scoped.

Fix Candidates

#	Source	Approach	Test Result	Files Changed	Notes
PR	PR #28879	Add explicit Shell item null guards in Windows ShellView.SwitchShellItem and iOS ShellRenderer.SetupCurrentShellItem; add device test	FAILED (Gate: testhost dependency abort, not functional assertion failure)	ShellView.cs, ShellRenderer.cs, ShellTests.cs	Original PR

---

🔬 Code Review — Deep Analysis

Code Review PR #28879

Independent Assessment

What this changes: Adds explicit InvalidOperationException guards for empty Shell state on Windows and iOS/MacCatalyst, plus shared device-test coverage.
Inferred motivation: Replace unclear null-reference failures with actionable Shell configuration errors consistent with Android.

Reconciliation with PR Narrative

Author claims: Fixes Windows empty-Shell NRE, aligns with Android, validates platforms.
Agreement/disagreement: Agrees for #21562. The link to #10041 is less direct.

Findings

No code findings.

Devil's Advocate

Checked callers, platform parity, tests, prior comments, and CI. Main risk is exception timing during handler creation, but current checks are green.

Verdict: LGTM

Confidence: high
Summary: Small, consistent, well-scoped fix. No comments posted.

---

🔧 Fix — Analysis & Comparison

Fix Candidates

#	Source	Approach	Test Result	Files Changed	Notes
1	try-fix	Validate in Windows ShellHandler.MapCurrentItem before ShellView.SwitchShellItem	Blocked (build passed; VSTest host missing Microsoft.TestPlatform.CoreUtilities)	1 file	Smaller Windows-only boundary guard; not better than PR parity fix
2	try-fix	Treat empty Shell as a temporary no-op on Windows	Blocked (build passed; same VSTest host failure)	1 file	Self-review found major semantic mismatch with expected InvalidOperationException and Android behavior
3	try-fix	Validate in Windows ShellHandler.SetVirtualView before mapper execution	Blocked (build passed; same VSTest host failure)	1 file	Earlier lifecycle failure; higher timing risk and Windows-only
4	try-fix	Add shared Shell.ValidateCurrentItem() helper used by Windows and iOS call sites	Blocked (build passed; same VSTest host failure)	3 files	Centralizes PR behavior but adds abstraction; not demonstrably better than PR
PR	PR #28879	Guard Windows ShellView.SwitchShellItem and iOS ShellRenderer.SetupCurrentShellItem; add device test	Failed in gate due VSTest host dependency abort	3 files	Original PR; code review LGTM

Cross-Pollination

Model	Round	New Ideas?	Details
claude-opus-4.6	2	No	NO NEW IDEAS
claude-opus-4.7	2	Yes	Shared Shell invariant/core validation before platform call sites
gpt-5.3-codex	2	Yes	Shared handler attachment validation before platform renderer runs
gpt-5.5	2	No	NO NEW IDEAS; remaining shared validation idea is not clearly better and risks transient empty-Shell scenarios

Exhausted: Yes
Selected Fix: PR's fix - No alternative candidate passed tests due the local Windows VSTest host dependency blocker, and none was demonstrably better on code review. Candidate 2 is semantically worse. Candidates 1 and 3 are narrower Windows-only fixes. Candidate 4 centralizes the PR behavior but adds abstraction without a clear benefit over the simple local guards.

Common Test Blocker

All candidate builds succeeded, then Windows test execution aborted before test assertions with:

System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.TestPlatform.CoreUtilities, Version=15.0.0.0'

This matches the prior gate failure and prevents claiming any candidate as passing.

---

📋 Report — Final Recommendation

Comparative Fix Report - PR #28879

Inputs Compared

Candidate	Approach	Regression result	Assessment
pr	Guard Windows ShellView.SwitchShellItem and iOS/MacCatalyst ShellRenderer.SetupCurrentShellItem; add shared device test.	Failed/blocked by Windows VSTest host dependency abort, not a completed assertion failure.	Best balance of local null-boundary validation, cross-platform parity, and regression coverage.
pr-plus-reviewer	PR fix plus expert-review feedback.	Same as pr; no additional reviewer changes existed.	Equivalent to pr; no actionable inline findings.
try-fix-1	Validate Shell.CurrentItem in Windows ShellHandler.MapCurrentItem before calling SwitchShellItem.	Blocked by the same VSTest host dependency abort.	Viable Windows-only boundary guard, but narrower than the PR and does not align iOS/MacCatalyst behavior.
try-fix-2	Treat empty Windows Shell as a temporary no-op in ShellHandler.MapCurrentItem.	Blocked by the same VSTest host dependency abort; expected to fail the intended exception regression semantics.	Semantically worse: it changes product behavior to tolerate an empty Shell and diverges from Android/PR exception behavior.
try-fix-3	Throw in Windows ShellHandler.SetVirtualView before mapper execution.	Blocked by the same VSTest host dependency abort.	Viable but higher lifecycle-timing risk because it rejects the Shell earlier than the null-consuming platform call site and remains Windows-only.
try-fix-4	Add shared Shell.ValidateCurrentItem() and call it from Windows/iOS call sites.	Blocked by the same VSTest host dependency abort.	Functionally close to the PR, but adds a shared abstraction for only two call sites without a clear reliability benefit.

Ranking

1. pr - Winning candidate. It fixes the known Windows null dereference at the platform boundary, aligns iOS/MacCatalyst behavior with existing Android-style Shell validation, and includes targeted regression coverage.
2. pr-plus-reviewer - Tied functionally with pr, but not selected separately because the expert reviewer found no actionable changes to apply; it is identical to the raw PR fix.
3. try-fix-4 - Closest alternative behaviorally, but the new shared helper is unnecessary abstraction for a small localized guard.
4. try-fix-1 - Smaller Windows-only fix, but it does not address cross-platform exception alignment.
5. try-fix-3 - Windows-only and validates earlier in the handler lifecycle, increasing the chance of affecting transient initialization scenarios.
6. try-fix-2 - Lowest-ranked candidate because it intentionally changes the expected behavior from throwing InvalidOperationException to silently accepting an empty Shell.

Test Evidence

No candidate has passing regression-test evidence in the saved artifacts because the Windows test run aborted before assertions with:

System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.TestPlatform.CoreUtilities, Version=15.0.0.0'

Because there are no candidates with completed passing regression tests, the winner is selected by code correctness and risk. try-fix-2 is additionally ranked below the other blocked candidates because its behavior conflicts with the intended exception-based regression test.

Winner

Winner: pr

The raw PR fix is the best candidate. The expert reviewer produced no actionable findings, making pr-plus-reviewer identical; all independent try-fix candidates were either narrower, higher-risk, or semantically inconsistent with the intended behavior.

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