[🐛 Bug]: WebDriver throws NullReferenceException when calling StartEventMonitoring with EventFiringWebDriver

[elgatov]

What happened?

Creating a JavaScriptEngine with an EventFiringWebDriver as parameter will throw a NullReferenceException when calling monitor.StartEventMonitoring();

I believe line 57 in

selenium/dotnet/src/webdriver/JavaScriptEngine.cs

Lines 48 to 64 in 5713de4

	public JavaScriptEngine(IWebDriver driver)
	{
	// Use of Lazy<T> means this exception won't be thrown until the user first
	// attempts to access the DevTools session, probably on the first call to
	// StartEventMonitoring() or in adding scripts to the instance.
	this.driver = driver;
	this.session = new Lazy<DevToolsSession>(() =>
	{
	IDevTools devToolsDriver = driver as IDevTools;
	if (session == null)
	{
	throw new WebDriverException("Driver must implement IDevTools to use these features");
	}
	return devToolsDriver.GetDevToolsSession();
	});
	}

should be changed to if (devToolsDriver == null) to correctly throw a WebDriverException when trying to use a non-compatible webdriver

How can we reproduce the issue?

using (var driver = new EventFiringWebDriver(new ChromeDriver()))
            {
                IJavaScriptEngine monitor = new JavaScriptEngine(driver);
                await monitor.StartEventMonitoring();
            }

Relevant log output

Message: 
Test method WebDriver.JavascriptEngine.Tests.UnitTest2.TestMethod1 threw exception: 
System.NullReferenceException: Object reference not set to an instance of an object.

  Stack Trace: 
<.ctor>b__0() line 62
Lazy`1.CreateValue()
Lazy`1.LazyInitValue()
Lazy`1.get_Value()
<StartEventMonitoring>d__24.MoveNext() line 116
--- End of stack trace from previous location where exception was thrown ---
TaskAwaiter.ThrowForNonSuccess(Task task)
TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
TaskAwaiter.GetResult()
<TestMethod1>d__5.MoveNext() line 80
--- End of stack trace from previous location where exception was thrown ---
TaskAwaiter.ThrowForNonSuccess(Task task)
TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
ThreadOperations.ExecuteWithAbortSafety(Action action)

Operating System

Windows 10

Selenium version

.Net Framework 4.8

What are the browser(s) and version(s) where you see this issue?

Chrome 102

What are the browser driver(s) and version(s) where you see this issue?

ChromeDriver 102.0.5005.6102

Are you using Selenium Grid?

No response

[github-actions]

@elgatov, thank you for creating this issue. We will troubleshoot it as soon as we can.

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[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.