Warn on nested js handle (#915)

* Warn on nested js handle

* Test ElementHandle

Author: kblok

lib/PuppeteerSharp.Tests/PageTests/EvaluateTests.cs

@@ -4,7 +4,7 @@
 using Newtonsoft.Json.Linq;
 using Xunit;
 using Xunit.Abstractions;
-using PuppeteerSharp.Helpers;
+using PuppeteerSharp.Helpers.Json;
 
 namespace PuppeteerSharp.Tests.PageTests
 {
@@ -177,6 +177,28 @@ public async Task ShouldAcceptObjectHandleToPrimitiveTypes()
             Assert.True(isFive);
         }
 
+        [Fact]
+        public async Task ShouldWarnOnNestedObjectHandles()
+        {
+            var handle = await Page.EvaluateFunctionHandleAsync("() => document.body");
+            var elementHandle = handle as ElementHandle;
+
+            var exception = await Assert.ThrowsAsync<EvaluationFailedException>(()
+                => Page.EvaluateFunctionHandleAsync(
+                    "opts => opts.elem.querySelector('p')",
+                    new { elem = handle }));
+
+            Assert.Contains("Are you passing a nested JSHandle?", exception.Message);
+
+            //Check with ElementHandle
+            exception = await Assert.ThrowsAsync<EvaluationFailedException>(()
+                => Page.EvaluateFunctionHandleAsync(
+                    "opts => opts.elem.querySelector('p')",
+                    new { elem = elementHandle }));
+
+            Assert.Contains("Are you passing a nested JSHandle?", exception.Message);
+        }
+
         [Fact]
         public async Task ShouldWorkFromInsideAnExposedFunction()
         {

lib/PuppeteerSharp/Browser.cs

@@ -6,6 +6,7 @@
 using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 using PuppeteerSharp.Helpers;
+using PuppeteerSharp.Helpers.Json;
 using PuppeteerSharp.Messaging;
 
 namespace PuppeteerSharp

lib/PuppeteerSharp/CDPSession.cs

@@ -1,14 +1,12 @@
 using System;
 using System.Collections.Concurrent;
-using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
-using Newtonsoft.Json.Serialization;
-using PuppeteerSharp.Helpers;
+using PuppeteerSharp.Helpers.Json;
 using PuppeteerSharp.Messaging;
 
 namespace PuppeteerSharp

lib/PuppeteerSharp/Connection.cs

@@ -1,14 +1,13 @@
 using System;
 using System.Collections.Concurrent;
-using System.Collections.Generic;
 using System.Linq;
 using System.Net.WebSockets;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
-using PuppeteerSharp.Helpers;
+using PuppeteerSharp.Helpers.Json;
 using PuppeteerSharp.Messaging;
 using PuppeteerSharp.Transport;
 

lib/PuppeteerSharp/ElementHandle.cs

@@ -1,11 +1,10 @@
 using Microsoft.Extensions.Logging;
-using Newtonsoft.Json;
 using Newtonsoft.Json.Linq;
 using PuppeteerSharp.Helpers;
+using PuppeteerSharp.Helpers.Json;
 using PuppeteerSharp.Input;
 using PuppeteerSharp.Messaging;
 using System;
-using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Threading.Tasks;

lib/PuppeteerSharp/FrameManager.cs

@@ -6,6 +6,7 @@
 using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 using PuppeteerSharp.Helpers;
+using PuppeteerSharp.Helpers.Json;
 using PuppeteerSharp.Messaging;
 
 namespace PuppeteerSharp

lib/PuppeteerSharp/Helpers/FlexibleStringEnumConverter.cs renamed to lib/PuppeteerSharp/Helpers/Json/FlexibleStringEnumConverter.cs

@@ -2,7 +2,7 @@
 using Newtonsoft.Json;
 using Newtonsoft.Json.Converters;
 
-namespace PuppeteerSharp.Helpers
+namespace PuppeteerSharp.Helpers.Json
 {
     internal class FlexibleStringEnumConverter : StringEnumConverter
     {

lib/PuppeteerSharp/Helpers/HttpMethodConverter.cs renamed to lib/PuppeteerSharp/Helpers/Json/HttpMethodConverter.cs

@@ -2,16 +2,14 @@
 using System.Net.Http;
 using Newtonsoft.Json;
 
-namespace PuppeteerSharp.Helpers
+namespace PuppeteerSharp.Helpers.Json
 {
     internal class HttpMethodConverter : JsonConverter
     {
         public override bool CanConvert(Type objectType) => objectType == typeof(string);
 
         public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
-        {
-            return new HttpMethod((string)reader.Value);
-        }
+            => new HttpMethod((string)reader.Value);
 
         public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
         {

lib/PuppeteerSharp/Helpers/Json/JSHandleMethodConverter.cs

@@ -0,0 +1,19 @@
+using System;
+using Newtonsoft.Json;
+
+namespace PuppeteerSharp.Helpers.Json
+{
+    /// <summary>
+    /// JSHandleMethodConverter will throw an exception if a JSHandle object is trying to be serialized
+    /// </summary>
+    internal class JSHandleMethodConverter : JsonConverter
+    {
+        public override bool CanConvert(Type objectType) => false;
+
+        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
+            => null;
+
+        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
+            => throw new EvaluationFailedException("Unable to make function call. Are you passing a nested JSHandle?");
+    }
+}

lib/PuppeteerSharp/Helpers/JTokenExtensions.cs renamed to lib/PuppeteerSharp/Helpers/Json/JTokenExtensions.cs

@@ -2,7 +2,7 @@
 using Newtonsoft.Json.Linq;
 using Newtonsoft.Json.Serialization;
 
-namespace PuppeteerSharp.Helpers
+namespace PuppeteerSharp.Helpers.Json
 {
     /// <summary>
     /// A set of extension methods for JToken