Add missing query object tests (#2623)

Author: kblok

lib/PuppeteerSharp.Tests/QueryObjectsTests/QueryObjectsTests.cs

@@ -2,7 +2,7 @@
 using NUnit.Framework;
 using PuppeteerSharp.Nunit;
 
-namespace PuppeteerSharp.Tests.QueryObjectTests
+namespace PuppeteerSharp.Tests.QueryObjectsTests
 {
     public class QueryObjectsTests : PuppeteerPageBaseTest
     {
@@ -37,14 +37,46 @@ await Page.EvaluateFunctionAsync<int>(@"objects => {
             }", objectsHandle));
         }
 
+        [Test, Retry(2), PuppeteerTest("queryObjects.spec", "page.queryObjects", "should work for non-trivial page")]
+        public async Task ShouldWorkForNonTrivialPage()
+        {
+            await Page.GoToAsync(TestConstants.EmptyPage);
+            // Create a custom class
+            var classHandle = await Page.EvaluateFunctionHandleAsync(@"() => {
+                return class CustomClass { };
+            }");
+
+            // Create an instance.
+            await Page.EvaluateFunctionAsync(@"CustomClass => {
+                self.customClass = new CustomClass();
+            }", classHandle);
+
+            // Validate only one has been added.
+            var prototypeHandle = await Page.EvaluateFunctionHandleAsync(@"CustomClass => {
+                return CustomClass.prototype;
+            }", classHandle);
+
+            var objectsHandle = await Page.QueryObjectsAsync(prototypeHandle);
+            Assert.AreEqual(
+                1,
+                await Page.EvaluateFunctionAsync<int>(@"objects => {
+                    return objects.length;
+                }", objectsHandle));
+
+            // Check that instances.
+            Assert.True(await Page.EvaluateFunctionAsync<bool>(@"objects => {
+                return objects[0] === self.customClass;
+            }", objectsHandle));
+        }
+
         [Test, Retry(2), PuppeteerTest("queryObjects.spec", "page.queryObjects", "should fail for disposed handles")]
         public async Task ShouldFailForDisposedHandles()
         {
             var prototypeHandle = await Page.EvaluateExpressionHandleAsync("HTMLBodyElement.prototype");
             await prototypeHandle.DisposeAsync();
             var exception = Assert.ThrowsAsync<PuppeteerException>(()
                 => Page.QueryObjectsAsync(prototypeHandle));
-            Assert.AreEqual("Prototype JSHandle is disposed!", exception.Message);
+            Assert.AreEqual("Prototype JSHandle is disposed!", exception!.Message);
         }
 
         [Test, Retry(2), PuppeteerTest("queryObjects.spec", "page.queryObjects", "should fail primitive values as prototypes")]
@@ -53,7 +85,7 @@ public async Task ShouldFailPrimitiveValuesAsPrototypes()
             var prototypeHandle = await Page.EvaluateExpressionHandleAsync("42");
             var exception = Assert.ThrowsAsync<PuppeteerException>(()
                 => Page.QueryObjectsAsync(prototypeHandle));
-            Assert.AreEqual("Prototype JSHandle must not be referencing primitive value", exception.Message);
+            Assert.AreEqual("Prototype JSHandle must not be referencing primitive value", exception!.Message);
         }
     }
 }