[dotnet] Propagate async throughout test setup and teardown

[RenderMichael]

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Description

Propagates async all the way to the top (where NUnit handles it) instead of GetAwaiter().GetResult()

Motivation and Context

Sync-over-async makes for bulkier code. It also prevents future SuppressThrowing optimizations.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

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PR Type

enhancement, tests

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Description

• Converted test setup and teardown methods to use async/await pattern across multiple test files.
• Replaced synchronous start and stop methods with async versions in EnvironmentManager, RemoteSeleniumServer, and TestWebServer.
• Improved code readability and potential performance by avoiding sync-over-async patterns.

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Changes walkthrough 📝

Relevant files

Enhancement

11 files ChromeSpecificTests.cs Convert Chrome test teardown to async                                        dotnet/test/chrome/ChromeSpecificTests.cs Added async keyword to RunAfterAnyTests method. Replaced synchronous stop method with StopAsync. +3/-2      AssemblyFixture.cs Update AssemblyFixture setup and teardown to async              dotnet/test/common/AssemblyFixture.cs Added async keyword to setup and teardown methods. Replaced synchronous start and stop methods with async versions. +7/-6      EnvironmentManager.cs Use async stop methods in EnvironmentManager destructor    dotnet/test/common/Environment/EnvironmentManager.cs Replaced synchronous stop methods with async versions in destructor. +2/-2      RemoteSeleniumServer.cs Convert RemoteSeleniumServer start and stop to async          dotnet/test/common/Environment/RemoteSeleniumServer.cs Converted Start and Stop methods to async. Replaced synchronous HTTP requests with async versions. +5/-4      TestWebServer.cs Convert TestWebServer start and stop to async                        dotnet/test/common/Environment/TestWebServer.cs Converted Start and Stop methods to async. Replaced synchronous HTTP requests with async versions. +5/-4      AssemblyTeardown.cs Update Edge assembly setup and teardown to async                  dotnet/test/edge/AssemblyTeardown.cs Added async keyword to setup and teardown methods. Replaced synchronous stop method with StopAsync. +5/-4      AssemblyTeardown.cs Update Firefox assembly setup and teardown to async            dotnet/test/firefox/AssemblyTeardown.cs Added async keyword to setup and teardown methods. Replaced synchronous stop method with StopAsync. +5/-4      AssemblyTeardown.cs Update IE assembly setup and teardown to async                      dotnet/test/ie/AssemblyTeardown.cs Added async keyword to setup and teardown methods. Replaced synchronous stop method with StopAsync. +5/-4      AssemblyTeardown.cs Update Remote assembly setup and teardown to async              dotnet/test/remote/AssemblyTeardown.cs Added async keyword to setup and teardown methods. Replaced synchronous start and stop methods with async versions. +7/-6      PopupWindowFinderTest.cs Update PopupWindowFinderTest setup and teardown to async  dotnet/test/support/UI/PopupWindowFinderTest.cs Added async keyword to setup and teardown methods. Replaced synchronous stop method with StopAsync. +5/-4      SelectBrowserTests.cs Update SelectBrowserTests setup and teardown to async        dotnet/test/support/UI/SelectBrowserTests.cs Added async keyword to setup and teardown methods. Replaced synchronous stop method with StopAsync. +5/-4

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[qodo-merge-pro]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 2 🔵🔵⚪⚪⚪

🧪 PR contains tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Potential Deadlock Using .Wait() on async tasks in the destructor could lead to deadlocks. Consider using a synchronous cleanup approach in the destructor instead. Error Handling Empty catch block silently swallows exceptions during server shutdown. Should at least log the error for debugging purposes.

[qodo-merge-pro]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Score
Possible issue	Replace blocking Wait() calls in destructor with proper disposal pattern to prevent potential deadlocks Using .Wait() in a destructor can lead to deadlocks. Consider implementing IDisposable pattern to properly handle async cleanup, or use a synchronous alternative if async operations are not critical during shutdown. dotnet/test/common/Environment/EnvironmentManager.cs [198-209] -~EnvironmentManager() +public void Dispose() { if (remoteServer != null) { - remoteServer.StopAsync().Wait(); + remoteServer.StopAsync().GetAwaiter().GetResult(); } if (webServer != null) { - webServer.StopAsync().Wait(); + webServer.StopAsync().GetAwaiter().GetResult(); } CloseCurrentDriver(); } Apply this suggestion Suggestion importance[1-10]: 9 Why: Using Wait() in destructors is a dangerous practice that can lead to deadlocks. Implementing IDisposable pattern is a critical improvement for proper resource cleanup and application stability.	9
General	Add ConfigureAwait(false) to async operations to prevent deadlocks and improve performance Add ConfigureAwait(false) to prevent potential deadlocks in ASP.NET contexts and improve performance by avoiding unnecessary context switches. dotnet/test/common/Environment/RemoteSeleniumServer.cs [71] -using var response = await httpClient.GetAsync("http://localhost:6000/wd/hub/status"); +using var response = await httpClient.GetAsync("http://localhost:6000/wd/hub/status").ConfigureAwait(false); Apply this suggestion Suggestion importance[1-10]: 7 Why: Adding ConfigureAwait(false) is an important practice in .NET async code to prevent potential deadlocks in ASP.NET contexts and improve performance by avoiding unnecessary synchronization context switches.	7

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[nvborisenko]

LGTM, thx Michael!

[nvborisenko]

Thank you, @RenderMichael !