Fix MAUI build queue timeout test flakiness

[James Newton-King (JamesNK)]

Description

The MAUI build queue launch-handoff tests used short wall-clock delays to exercise timeout behavior. Under heavy Windows CI contention, those timers could be delayed long enough for tests to exceed their outer timeout and fail intermittently.

This change makes the launch-handoff timeout use an injectable TimeProvider while preserving TimeProvider.System in production. The timeout tests now advance a FakeTimeProvider deterministically instead of depending on real 50 ms timers.

The MAUI test project also uses the shared DefaultTimeout helper for async operations that are expected to complete, preventing failures from hanging indefinitely and providing CI-aware timeout diagnostics. Intentional semaphore waits, cancellation waits, and timeout assertions retain their original semantics.

Validation:

dotnet test --project tests/Aspire.Hosting.Maui.Tests/Aspire.Hosting.Maui.Tests.csproj --no-restore --no-launch-profile -- --filter-not-trait "quarantined=true" --filter-not-trait "outerloop=true"
Passed: 204, Failed: 0, Skipped: 0

Fixes #18592

Checklist

• Is this feature complete?
  • Yes. Ready to ship.
  • No. Follow-up changes expected.
• Are you including unit tests for the changes and scenario tests if relevant?
  • Yes
  • No
• Did you add public API?
  • Yes
    • If yes, did you have an API Review for it?
      • Yes
      • No
    • Did you add <remarks /> and <code /> elements on your triple slash comments?
      • Yes
      • No
  • No
• Does the change make any security assumptions or guarantees?
  • Yes
    • If yes, have you done a threat model and had a security review?
      • Yes
      • No
  • No

[github-actions]

🚀 Dogfood this PR with:

⚠️ WARNING: Do not do this without first carefully reviewing the code of this PR to satisfy yourself it is safe.

curl -fsSL https://raw.githubusercontent.com/microsoft/aspire/main/eng/scripts/get-aspire-cli-pr.sh | bash -s -- 20064

Or

• Run remotely in PowerShell:

iex "& { $(irm https://raw.githubusercontent.com/microsoft/aspire/main/eng/scripts/get-aspire-cli-pr.ps1) } 20064"

[github-actions]

Tests selector

1 / 99 PR test projects · 2 PR jobs · 0 advisory-only targets, from 7 changed files.

Selected PR test projects (1 / 99)

Aspire.Hosting.Maui.Tests

Selected PR jobs (2)

extension-e2e, typescript-api-compat

Advisory workflow impact (0)

none

---

How these were chosen — grouped by what changed

🔧 src/Aspire.Hosting.Maui/Lifecycle/MauiBuildQueueEventSubscriber.cs (changed source)
→ 1 directly: Aspire.Hosting.Maui.Tests

🧪 tests/Aspire.Hosting.Maui.Tests/Aspire.Hosting.Maui.Tests.csproj (changed test)
→ 1 directly: Aspire.Hosting.Maui.Tests

🧪 tests/Aspire.Hosting.Maui.Tests/MauiBuildQueueTests.cs (changed test)
→ 1 directly: Aspire.Hosting.Maui.Tests

🧪 tests/Aspire.Hosting.Maui.Tests/MauiOtlpTemplateTests.cs (changed test)
→ 1 directly: Aspire.Hosting.Maui.Tests

🧪 tests/Aspire.Hosting.Maui.Tests/MauiPlatformExtensionsTests.cs (changed test)
→ 1 directly: Aspire.Hosting.Maui.Tests

🧪 tests/Aspire.Hosting.Maui.Tests/MauiWithArgsTests.cs (changed test)
→ 1 directly: Aspire.Hosting.Maui.Tests

🧪 tests/Aspire.Hosting.Maui.Tests/MauiiOSValidationTests.cs (changed test)
→ 1 directly: Aspire.Hosting.Maui.Tests

Job reasons

Job	Triggered by
extension-e2e	• src/Aspire.Hosting.Maui/Lifecycle/MauiBuildQueueEventSubscriber.cs • affected project Aspire.Hosting.Maui
typescript-api-compat	affected project Aspire.Hosting.Maui

---

Selection computed for commit 517eedf.

[Copilot]

🔵 Needs a closer look

The timeout watchdog can be mistaken for the expected build failure in one test.

Pull request overview

This PR makes MAUI build queue timeout tests deterministic and adds bounded async waits for CI diagnostics.

Changes:

• Injects TimeProvider while retaining system time in production.
• Uses FakeTimeProvider for timeout scenarios.
• Applies shared DefaultTimeout helpers across MAUI tests.
• Adds required testing support.

File summaries

File	Summary
tests/Aspire.Hosting.Maui.Tests/MauiWithArgsTests.cs	Bounds argument-evaluation awaits.
tests/Aspire.Hosting.Maui.Tests/MauiPlatformExtensionsTests.cs	Bounds asynchronous test operations.
tests/Aspire.Hosting.Maui.Tests/MauiOtlpTemplateTests.cs	Bounds environment evaluation.
tests/Aspire.Hosting.Maui.Tests/MauiiOSValidationTests.cs	Bounds validation event awaits.
tests/Aspire.Hosting.Maui.Tests/MauiBuildQueueTests.cs	Makes timeout scenarios deterministic and adds bounded waits.
tests/Aspire.Hosting.Maui.Tests/Aspire.Hosting.Maui.Tests.csproj	Adds testing package and shared timeout support.
src/Aspire.Hosting.Maui/Lifecycle/MauiBuildQueueEventSubscriber.cs	Adds injectable launch-handoff timeout scheduling.

Review details

Suppressed comments (1)

tests/Aspire.Hosting.Maui.Tests/MauiBuildQueueTests.cs:1103

• DefaultTimeout() throws TimeoutException when the publish task does not complete, but it is inside Assert.ThrowsAnyAsync<Exception>, so the test can accept its own watchdog exception as the expected build failure instead of proving that BuildTimeout produced the failure. Keep the timeout guard outside the broad exception assertion (first verify the task completed within the budget, then assert its exception), or assert the permitted production exception types while distinguishing the watchdog timeout.

            CancellationToken.None)).DefaultTimeout();

• Files reviewed: 7/7 changed files
• Comments generated: 0
• Review effort level: Lite

---

💡 Add a code-review agent skill for context-aware, tailored reviews. Learn more in the docs.