nvborisenko · Oct 1, 2026 · Oct 1, 2026 · Oct 1, 2026 · Oct 1, 2026 · Oct 1, 2026
diff --git a/dotnet/private/dotnet_nunit_test_suite.bzl b/dotnet/private/dotnet_nunit_test_suite.bzl
@@ -88,7 +88,7 @@ _BROWSERS = {
             "ActiveDriverConfig=IE",
         ],
         "data": [],
-        "tags": [],
+        "tags": ["exclusive-if-local"],  # IE cannot run in parallel.
         "target_compatible_with": ["@platforms//os:windows"],
     },
     "safari": {
@@ -97,7 +97,7 @@ _BROWSERS = {
             "ActiveDriverConfig=Safari",
         ],
         "data": [],
-        "tags": [],
+        "tags": ["exclusive-if-local"],  # Safari cannot run in parallel.
         "target_compatible_with": ["@platforms//os:osx"],
     },
     "remote": {

diff --git a/dotnet/test/remote/AssemblyTeardown.cs b/dotnet/test/remote/AssemblyTeardown.cs
@@ -20,6 +20,9 @@
 using NUnit.Framework;
 using OpenQA.Selenium.Testing.NUnit;
 
+[assembly: Parallelizable(ParallelScope.Fixtures)]
+[assembly: SingleSessionBrowser(Browser.Safari, Browser.IE)]
+
 [SetUpFixture]
 #pragma warning disable // Outside a namespace to affect the entire assembly
 public class AssemblyTeardown : AssemblyFixtureBase

diff --git a/dotnet/test/remote/RemoteWebDriverSpecificTests.cs b/dotnet/test/remote/RemoteWebDriverSpecificTests.cs
@@ -52,7 +52,7 @@ public void Teardown()
     [NeedsFreshDriver(IsCreatedAfterTest = true)]
     public void ShouldBeAbleToCreateRemoteWebDriverWithNoSlashAtEndOfUri()
     {
-        EnvironmentManager.Instance.CloseCurrentDriver();
+        CloseDriver();
         DriverOptions options = OperatingSystem.IsWindows() ? new EdgeOptions() : new ChromeOptions();
         RemoteWebDriver noSlashDriver = new RemoteWebDriver(RemoteSeleniumServer.ServerUri, options);
         noSlashDriver.Url = Urls.JavascriptPage;

diff --git a/dotnet/test/support/AssemblyFixture.cs b/dotnet/test/support/AssemblyFixture.cs
@@ -17,6 +17,9 @@
 // under the License.
 // </copyright>
 
+[assembly: Parallelizable(ParallelScope.Fixtures)]
+[assembly: SingleSessionBrowser(Browser.Safari, Browser.IE)]
+
 namespace OpenQA.Selenium.Support.Tests;
 
 [SetUpFixture]

diff --git a/dotnet/test/testing.nunit/AssemblyFixtureBase.cs b/dotnet/test/testing.nunit/AssemblyFixtureBase.cs
@@ -42,7 +42,6 @@ public async Task RunBeforeAnyTestAsync()
     [OneTimeTearDown]
     public async Task RunAfterAnyTestsAsync()
     {
-        EnvironmentManager.Instance.CloseCurrentDriver();
         await EnvironmentManager.Instance.WebServer.StopAsync();
         if (StartRemoteServer)
         {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/DefaultSafariDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/DefaultSafariDriver.cs
@@ -26,7 +26,7 @@ namespace OpenQA.Selenium.Testing.NUnit.DriverConfigs;
 // constructor.
 public class DefaultSafariDriver : SafariDriver
 {
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public DefaultSafariDriver(SafariOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/DevChannelChromeDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/DevChannelChromeDriver.cs
@@ -48,7 +48,7 @@ public DevChannelChromeDriver()
     {
     }
 
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public DevChannelChromeDriver(ChromeOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/DevChannelEdgeDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/DevChannelEdgeDriver.cs
@@ -28,7 +28,7 @@ public DevChannelEdgeDriver()
     {
     }
 
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public DevChannelEdgeDriver(EdgeOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/EdgeInternetExplorerModeDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/EdgeInternetExplorerModeDriver.cs
@@ -31,7 +31,7 @@ public EdgeInternetExplorerModeDriver()
     {
     }
 
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public EdgeInternetExplorerModeDriver(InternetExplorerOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/NightlyChannelFirefoxDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/NightlyChannelFirefoxDriver.cs
@@ -31,7 +31,7 @@ public NightlyChannelFirefoxDriver()
     {
     }
 
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public NightlyChannelFirefoxDriver(FirefoxOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/SafariTechnologyPreviewDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/SafariTechnologyPreviewDriver.cs
@@ -31,7 +31,7 @@ public SafariTechnologyPreviewDriver()
     {
     }
 
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public SafariTechnologyPreviewDriver(SafariOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/StableChannelChromeDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/StableChannelChromeDriver.cs
@@ -28,7 +28,7 @@ public StableChannelChromeDriver()
     {
     }
 
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public StableChannelChromeDriver(ChromeOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/StableChannelEdgeDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/StableChannelEdgeDriver.cs
@@ -29,7 +29,7 @@ public StableChannelEdgeDriver()
     {
     }
 
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public StableChannelEdgeDriver(EdgeOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverConfigs/StableChannelFirefoxDriver.cs b/dotnet/test/testing.nunit/DriverConfigs/StableChannelFirefoxDriver.cs
@@ -31,7 +31,7 @@ public StableChannelFirefoxDriver()
     {
     }
 
-    // Required for dynamic setting with `EnvironmentManager.Instance.CreateDriverInstance(options)`
+    // Required for dynamic setting with `DriverFactory.CreateDriver(options)`
     public StableChannelFirefoxDriver(FirefoxOptions options)
         : base(options)
     {

diff --git a/dotnet/test/testing.nunit/DriverTestFixture.cs b/dotnet/test/testing.nunit/DriverTestFixture.cs
@@ -44,17 +44,20 @@ public bool IsNativeEventsEnabled
         }
     }
 
+    protected DriverFactory DriverFactory { get; private set; }
+
     [OneTimeSetUp]
-    public void SetUp()
+    public void InitFixtureDriver()
     {
-        Driver = EnvironmentManager.Instance.GetCurrentDriver();
+        DriverFactory = CreateDriverFactory();
+        Driver = CreateDriverInstance();
     }
 
     [OneTimeTearDown]
-    public void TearDown()
+    public void DisposeFixtureDriver()
     {
-        EnvironmentManager.Instance.CloseCurrentDriver();
         Driver?.Dispose();
+        Driver = null;
     }
 
     [TearDown]
@@ -63,16 +66,30 @@ public void ResetOnError()
         if (TestContext.CurrentContext.Result.Outcome == ResultState.Error)
         {
             Driver?.Dispose();
-            Driver = EnvironmentManager.Instance.CreateFreshDriver();
+            Driver = CreateDriverInstance();
         }
     }
 
-    /// <summary>
-    /// Exists because a given test might require a fresh driver.
-    /// </summary>
-    protected void CreateFreshDriver()
+    protected virtual DriverFactory CreateDriverFactory()
+    {
+        return new DriverFactory(EnvironmentManager.Instance);
+    }
+
+    protected IWebDriver CreateDriverInstance(DriverOptions options = null)
+    {
+        return DriverFactory.CreateDriver(options);
+    }
+
+    protected internal void CloseDriver()
+    {
+        Driver?.Dispose();
+        Driver = null;
+    }
+
+    protected internal void CreateFreshDriver()
     {
-        Driver = EnvironmentManager.Instance.CreateFreshDriver();
+        CloseDriver();
+        Driver = CreateDriverInstance();
     }
 
     protected void WaitFor(Func<bool> waitFunction, string timeoutMessage)
@@ -87,17 +104,16 @@ protected T WaitFor<T>(Func<T> waitFunction, string timeoutMessage)
 
     protected T WaitFor<T>(Func<T> waitFunction, TimeSpan timeout, string timeoutMessage)
     {
-        var waiter = new WebDriverWait(Driver, timeout)
+        // Not bound to Driver: callers may wait on a local driver while the fixture driver is closed.
+        var waiter = new DefaultWait<Func<T>>(waitFunction)
         {
+            Timeout = timeout,
             PollingInterval = TimeSpan.FromMilliseconds(100),
             Message = $"Condition timed out: {timeoutMessage}",
         };
 
         waiter.IgnoreExceptionTypes(typeof(Exception));
 
-        return waiter.Until((driver) =>
-        {
-            return waitFunction();
-        });
+        return waiter.Until(func => func());
     }
 }
diff --git a/dotnet/test/testing.nunit/Environment/DriverFactory.cs b/dotnet/test/testing.nunit/Environment/DriverFactory.cs
@@ -17,6 +17,7 @@
 // under the License.
 // </copyright>
 
+using System.Collections.Concurrent;
 using System.IO;
 using System.Reflection;
 using OpenQA.Selenium.Chrome;
@@ -30,20 +31,37 @@ namespace OpenQA.Selenium.Testing.NUnit.Environment;
 
 public class DriverFactory
 {
+    private static readonly ConcurrentDictionary<string, Type> driverTypes = new();
+
+    private readonly Type driverType;
     private readonly string driverPath;
     private readonly string browserBinaryLocation;
+    private readonly bool headless;
     private readonly Dictionary<Browser, Type> serviceTypes = new Dictionary<Browser, Type>();
     private readonly Dictionary<Browser, Type> optionsTypes = new Dictionary<Browser, Type>();
 
-    public DriverFactory(string driverPath, string browserBinaryLocation)
+    public DriverFactory(EnvironmentManager environment)
     {
-        this.driverPath = driverPath;
-        this.browserBinaryLocation = browserBinaryLocation;
+        this.driverType = driverTypes.GetOrAdd(environment.DriverTypeName, ResolveDriverType);
+        this.driverPath = environment.DriverServiceLocation;
+        this.browserBinaryLocation = environment.BrowserLocation;
+        this.headless = environment.Headless;
 
         this.PopulateServiceTypes();
         this.PopulateOptionsTypes();
     }
 
+    private static Type ResolveDriverType(string driverTypeName)
+    {
+        // Bazel uses unpredictable assembly names to execute tests, so search all loaded assemblies.
+        return AppDomain.CurrentDomain.GetAssemblies()
+            .AsEnumerable()
+            .Reverse()
+            .Select(assembly => assembly.GetType(driverTypeName))
+            .FirstOrDefault(t => t != null)
+            ?? throw new ArgumentOutOfRangeException(nameof(driverTypeName), $"Unable to find driver type {driverTypeName}");
+    }
+
     private void PopulateOptionsTypes()
     {
         this.optionsTypes[Browser.Chrome] = typeof(ChromeOptions);
@@ -64,12 +82,7 @@ private void PopulateServiceTypes()
 
     public event EventHandler<DriverStartingEventArgs> DriverStarting;
 
-    public IWebDriver CreateDriver(Type driverType, bool logging = false)
-    {
-        return CreateDriverWithOptions(driverType, null, logging);
-    }
-
-    public IWebDriver CreateDriverWithOptions(Type driverType, DriverOptions driverOptions, bool logging = false)
+    public IWebDriver CreateDriver(DriverOptions driverOptions = null, bool logging = false)
     {
         Browser browser = Browser.All;
         DriverService service = null;
@@ -84,7 +97,7 @@ public IWebDriver CreateDriverWithOptions(Type driverType, DriverOptions driverO
 
             var chromeOptions = (ChromeOptions)options;
             chromeOptions.AddArguments("--no-sandbox", "--disable-dev-shm-usage");
-            if (EnvironmentManager.Instance.Headless)
+            if (this.headless)
             {
                 chromeOptions.AddArgument("--headless");
             }
@@ -106,7 +119,7 @@ public IWebDriver CreateDriverWithOptions(Type driverType, DriverOptions driverO
 
             var edgeOptions = (EdgeOptions)options;
             edgeOptions.AddArguments("--no-sandbox", "--disable-dev-shm-usage");
-            if (EnvironmentManager.Instance.Headless)
+            if (this.headless)
             {
                 edgeOptions.AddArgument("--headless");
             }
@@ -135,7 +148,7 @@ public IWebDriver CreateDriverWithOptions(Type driverType, DriverOptions driverO
         {
             browser = Browser.Firefox;
             options = GetDriverOptions<FirefoxOptions>(driverType, driverOptions);
-            if (EnvironmentManager.Instance.Headless)
+            if (this.headless)
             {
                 ((FirefoxOptions)options).AddArgument("-headless");
             }