Changes to .NET ExecuteJavaScript extension method for converting result

Now validates that the ExecuteJavaScript extension method will correctly
detect if the script result is convertable to the generic type.

Signed-off-by: Jim Evans <[email protected]>

dotnet/src/support/Extensions/WebDriverExtensions.cs

@@ -86,7 +86,7 @@ public static T ExecuteJavaScript<T>(this IWebDriver driver, string script, para
             }
 
             object result = executor.ExecuteScript(script, args);
-            if (!result.GetType().IsAssignableFrom(typeof(T)))
+            if (typeof (T).IsInstanceOfType(result) == false)
             {
                 throw new WebDriverException("Script returned a value, but the result could not be cast to the desired type");
             }

dotnet/test/support/Extensions/ExecuteJavaScriptTest.cs

@@ -0,0 +1,104 @@
+using System.Collections;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+
+using NMock2;
+
+using NUnit.Framework;
+
+namespace OpenQA.Selenium.Support.Extensions
+{
+    public interface IJavaScriptExecutingWebDriver : IWebDriver, IJavaScriptExecutor
+    {
+    }
+
+    public class SubClassOfReadOnlyCollectionOfObject : ReadOnlyCollection<object>
+    {
+        public SubClassOfReadOnlyCollectionOfObject(IList<object> list) : base(list)
+        {
+        }
+    }
+
+    [TestFixture]
+    public class ExecuteJavaScriptTest
+    {
+        private const string JavaScript = "Hello, World";
+        private static readonly object[] JavaScriptParameters = new object[0];
+
+        private Mockery mocks;
+        private IJavaScriptExecutingWebDriver driver;
+
+        [SetUp]
+        public void TestSetUp()
+        {
+            mocks = new Mockery();
+
+            driver = mocks.NewMock<IJavaScriptExecutingWebDriver>();
+        }
+
+        [Test]
+        public void ShouldConvertToIEnumerable()
+        {
+            var expected = new ReadOnlyCollection<object>(new List<object>());
+
+            Expect.Once.On(driver)
+                .Method("ExecuteScript")
+                .With(JavaScript, JavaScriptParameters)
+                .Will(Return.Value(expected));
+
+            Assert.That(() => driver.ExecuteJavaScript<IEnumerable>(JavaScript, JavaScriptParameters), Throws.Nothing);
+        }
+
+        [Test]
+        public void ShouldConvertToIEnumerableOfObject()
+        {
+            var expected = new ReadOnlyCollection<object>(new List<object>());
+
+            Expect.Once.On(driver)
+                .Method("ExecuteScript")
+                .With(JavaScript, JavaScriptParameters)
+                .Will(Return.Value(expected));
+
+            Assert.That(() => driver.ExecuteJavaScript<IEnumerable<object>>(JavaScript, JavaScriptParameters), Throws.Nothing);
+        }
+
+        [Test]
+        public void ShouldNotConvertToIEnumerableOfInteger()
+        {
+            var expected = new ReadOnlyCollection<object>(new List<object>());
+
+            Expect.Once.On(driver)
+                .Method("ExecuteScript")
+                .With(JavaScript, JavaScriptParameters)
+                .Will(Return.Value(expected));
+
+            Assert.That(() => driver.ExecuteJavaScript<IEnumerable<int>>(JavaScript, JavaScriptParameters), Throws.InstanceOf<WebDriverException>());
+        }
+
+        [Test]
+        public void ShouldConvertToReadOnlyCollectionOfObject()
+        {
+            var expected = new ReadOnlyCollection<object>(new List<object>());
+
+            Expect.Once.On(driver)
+                .Method("ExecuteScript")
+                .With(JavaScript, JavaScriptParameters)
+                .Will(Return.Value(expected));
+
+            Assert.That(() => driver.ExecuteJavaScript<ReadOnlyCollection<object>>(JavaScript, JavaScriptParameters), Throws.Nothing);
+        }
+
+        [Test]
+        public void ShouldNotConvertToSubClassOfReadOnlyCollectionOfObject()
+        {
+            var expected = new ReadOnlyCollection<object>(new List<object>());
+
+            Expect.Once.On(driver)
+                .Method("ExecuteScript")
+                .With(JavaScript, JavaScriptParameters)
+                .Will(Return.Value(expected));
+
+            Assert.That(() => driver.ExecuteJavaScript<SubClassOfReadOnlyCollectionOfObject>(JavaScript, JavaScriptParameters), Throws.InstanceOf<WebDriverException>());
+        }
+    }
+}

dotnet/test/support/WebDriver.Support.Tests.csproj

@@ -78,6 +78,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Events\EventFiringWebDriverTest.cs" />
+    <Compile Include="Extensions\ExecuteJavaScriptTest.cs" />
     <Compile Include="PageObjects\ByChainedBrowserTests.cs" />
     <Compile Include="PageObjects\ByChainedTests.cs" />
     <Compile Include="PageObjects\FindsByAttributeTests.cs" />