[dotnet] Modernize exception handling in tests

[RenderMichael]

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Description

This uses modern methods when making assertions or suppressions of exceptions.

Motivation and Context

Modernization and avoiding first-chance exceptions.

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

• Modernized exception handling across multiple test files by replacing traditional try-catch blocks with modern assertion methods using Assert.That.
• Improved code readability and conciseness by removing redundant exception handling and using task suppression where applicable.
• Reformatted large JavaScript strings for better readability.
• Enhanced test reliability by using more precise exception expectations.

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Changes walkthrough 📝

Relevant files

Enhancement

10 files AlertsTest.cs Modernize exception handling in AlertsTest                              dotnet/test/common/AlertsTest.cs Replaced try-catch blocks with modern assertion methods. Used Assert.That with exception expectations. +7/-14    NetworkEventsTest.cs Update exception handling in NetworkEventsTest                      dotnet/test/common/BiDi/Network/NetworkEventsTest.cs Replaced try-catch with task suppression for navigation. Used ConfigureAwaitOptions.SuppressThrowing. +2/-5      CorrectEventFiringTest.cs Simplify exception handling in CorrectEventFiringTest        dotnet/test/common/CorrectEventFiringTest.cs Simplified exception handling with assertions. Removed unnecessary try-catch blocks. +4/-12    ElementAttributeTest.cs Refactor exception handling in ElementAttributeTest            dotnet/test/common/ElementAttributeTest.cs Replaced try-catch blocks with Assert.That for exceptions. Improved readability and conciseness. +6/-14    RemoteSeleniumServer.cs Enhance HTTP request handling in RemoteSeleniumServer        dotnet/test/common/Environment/RemoteSeleniumServer.cs Used task suppression for HTTP requests. Removed redundant exception handling. +7/-16    TestWebServer.cs Simplify HTTP request handling in TestWebServer                    dotnet/test/common/Environment/TestWebServer.cs Simplified HTTP request handling with task suppression. Removed unnecessary try-catch blocks. +2/-11    ExecutingJavascriptTest.cs Modernize exception handling in ExecutingJavascriptTest    dotnet/test/common/ExecutingJavascriptTest.cs Used Assert.That for exception expectations. Reformatted large JavaScript string for readability. +54/-13  FrameSwitchingTest.cs Update frame switching exception handling                                dotnet/test/common/FrameSwitchingTest.cs Replaced try-catch blocks with modern assertions. Improved frame switching tests. +7/-20    TargetLocatorTest.cs Refactor exception handling in TargetLocatorTest                  dotnet/test/common/TargetLocatorTest.cs Replaced try-catch blocks with Assert.That. Improved test readability and conciseness. +17/-28  WindowSwitchingTest.cs Modernize exception handling in WindowSwitchingTest            dotnet/test/common/WindowSwitchingTest.cs Used Assert.That for exception handling. Simplified window switching tests. +21/-46

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PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 3 🔵🔵🔵⚪⚪

🧪 PR contains tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Error Handling The suppression of navigation errors may hide important failure cases that should be handled explicitly Error Handling Suppressing HTTP request exceptions without any logging or fallback behavior could mask server connectivity issues Code Smell The AlertToBePresent method has empty try-catch blocks that could be simplified or removed

[codiumai-pr-agent-pro]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Score
Possible issue	Method ignores provided locator parameter and uses hardcoded selector instead The ElementToBePresent method returns null when element is not found, but doesn't properly handle the locator parameter. The method should use the provided locator instead of hardcoding By.Id. dotnet/test/common/AlertsTest.cs [523] -return driver.FindElement(By.Id("open-page-with-onunload-alert")); +return driver.FindElement(locator); Apply this suggestion Suggestion importance[1-10]: 8 Why: The method ignores the locator parameter and uses a hardcoded selector, which is a significant bug that could cause incorrect behavior in tests using this method with different locators.	8
General	Add delay between server status check retries to prevent overwhelming the server The server status check should include a delay between retries to avoid overwhelming the server with rapid requests. Add a small delay in the polling loop. dotnet/test/common/Environment/RemoteSeleniumServer.cs [67-71] while (!isRunning && DateTime.Now < timeout) { var statusTask = httpClient.GetAsync("http://localhost:6000/wd/hub/status"); await ((Task)statusTask).ConfigureAwait(ConfigureAwaitOptions.SuppressThrowing); + await Task.Delay(100); } Apply this suggestion Suggestion importance[1-10]: 6 Why: Adding a delay between retries is a good practice to prevent excessive server load and potential resource exhaustion, though the current implementation would still work without it.	6
	Broaden exception handling to catch all WebDriver exceptions when checking for alerts The AlertToBePresent method returns null when no alert is present but doesn't properly handle exceptions other than NoAlertPresentException. Add handling for other potential exceptions. dotnet/test/common/WindowSwitchingTest.cs [478-485] try { return driver.SwitchTo().Alert(); } -catch (NoAlertPresentException) +catch (WebDriverException) { return null; } Apply this suggestion Suggestion importance[1-10]: 4 Why: While catching WebDriverException would make the code more robust, the current implementation focusing on NoAlertPresentException is functionally correct for most use cases.	4

💡 Need additional feedback ? start a PR chat

[RenderMichael]

@nvborisenko Feedback has been addressed, this PR is ready for another look

The feedback so far could be used to improve already-existing tests, but I wanted to keep this PR within reason. Maybe that can be a follow-up

[RenderMichael]

Test failures are for tests I did not touch, such as shadow root exceptions not being thrown on firefox

[nvborisenko]

Thank you, @RenderMichael ! CI is failing due to unrelated changes (ShadowRoot).