[REGRESSION]: QuerySelectorAllAsync causes InvalidCastException

[JustusGreiberORGADATA]

Context:

• GOOD Playwright Version: 1.40.0
• BAD Playwright Version: 1.41.0
• Operating System: Windows
• Extra: <TargetFramework>net6.0</TargetFramework>

Code Snippet

Project at https://github.com/JustusGreiberORGADATA/playwright-reproduction

using System.Threading.Tasks;
using Microsoft.Playwright;

using (var playwright = await Playwright.CreateAsync())
await using (var browser = await playwright.Chromium.LaunchAsync())
await using (var context = await browser.NewContextAsync()) {
        var page = await context.NewPageAsync();
        await page.GotoAsync("https://www.theverge.com");
        Console.WriteLine((await page.QuerySelectorAllAsync(".flex")).Count);
}

Prints stacktrace

Unhandled exception. System.InvalidCastException: Unable to cast object of type 'Microsoft.Playwright.Transport.Converters.ChannelToGuidConverter' to type 'System.Text.Json.Serialization.JsonConverter`1[Microsoft.Playwright.Core.ElementHandle]'.
   at System.Text.Json.Serialization.JsonCollectionConverter`2.GetElementConverter(JsonTypeInfo elementTypeInfo)
   at System.Text.Json.Serialization.JsonCollectionConverter`2.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, TCollection& value)
   at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
   at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, JsonSerializerOptions options, ReadStack& state)
   at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan`1 utf8Json, JsonTypeInfo jsonTypeInfo, Nullable`1 actualByteCount)
   at System.Text.Json.JsonSerializer.ReadUsingMetadata[TValue](JsonElement element, JsonTypeInfo jsonTypeInfo)
   at Microsoft.Playwright.Helpers.JsonExtensions.ToObject[T](JsonElement element, JsonSerializerOptions options) in /_/src/Playwright/Helpers/JsonExtensions.cs:line 52
   at Microsoft.Playwright.Transport.Connection.InnerSendMessageToServerAsync[T](ChannelOwner object, String method, Dictionary`2 dictionary, Boolean keepNulls) in /_/src/Playwright/Transport/Connection.cs:line 222
   at Microsoft.Playwright.Transport.Connection.WrapApiCallAsync[T](Func`1 action, Boolean isInternal)
   at Microsoft.Playwright.Core.Frame.QuerySelectorAllAsync(String selector) in /_/src/Playwright/Core/Frame.cs:line 645
   at Program.<Main>$(String[] args) in D:\repos\playwright-reproduction\Program.cs:line 9
   at Program.<Main>$(String[] args) in D:\repos\playwright-reproduction\Program.cs:line 10
   at Program.<Main>$(String[] args) in D:\repos\playwright-reproduction\Program.cs:line 10
   at Program.<Main>(String[] args)

Describe the bug

This for some reason only happens if my TargetFramework is net6.0. On .net7.0 and .net8.0 everything works fine.

[mxschmitt]

I was able to reproduce, thanks for filing!

[daveaglick]

What timing! I actually came here to find/report something similar, but for me it happens when capturing console messages. Same error message:

Microsoft.Playwright.TargetClosedException : Unable to cast object of type 'Microsoft.Playwright.Transport.Converters.ChannelToGuidConverter' to type 'System.Text.Json.Serialization.JsonConverter`1[Microsoft.Playwright.Core.JSHandle]'.
  ----> System.InvalidCastException : Unable to cast object of type 'Microsoft.Playwright.Transport.Converters.ChannelToGuidConverter' to type 'System.Text.Json.Serialization.JsonConverter`1[Microsoft.Playwright.Core.JSHandle]'.
   at Microsoft.Playwright.Transport.Connection.InnerSendMessageToServerAsync[T](ChannelOwner object, String method, Dictionary`2 dictionary, Boolean keepNulls) in /_/src/Playwright/Transport/Connection.cs:line 208
   at Microsoft.Playwright.Transport.Connection.WrapApiCallAsync[T](Func`1 action, Boolean isInternal) in /_/src/Playwright/Transport/Connection.cs:line 538
   at Microsoft.Playwright.Core.Frame.GotoAsync(String url, FrameGotoOptions options) in /_/src/Playwright/Core/Frame.cs:line 792
   at Sipc.WebSite.Portal.Tests.FirstTestFixture.Test() in C:\Code\SIPC\Sipc.BackOffice\tests\Sipc.WebSite.Portal.Tests\FirstTestFixture.cs:line 72
   at NUnit.Framework.Internal.TaskAwaitAdapter.GenericAdapter`1.BlockUntilCompleted()
   at NUnit.Framework.Internal.MessagePumpStrategy.NoMessagePumpStrategy.WaitForCompletion(AwaitAdapter awaiter)
   at NUnit.Framework.Internal.AsyncToSyncAdapter.Await(Func`1 invoke)
   at NUnit.Framework.Internal.Commands.TestMethodCommand.RunTestMethod(TestExecutionContext context)
   at NUnit.Framework.Internal.Commands.TestMethodCommand.Execute(TestExecutionContext context)
   at NUnit.Framework.Internal.Commands.BeforeAndAfterTestCommand.<>c__DisplayClass1_0.<Execute>b__0()
   at NUnit.Framework.Internal.Commands.DelegatingTestCommand.RunTestMethodInThreadAbortSafeZone(TestExecutionContext context, Action action)
--InvalidCastException
   at System.Text.Json.Serialization.JsonCollectionConverter`2.GetElementConverter(JsonTypeInfo elementTypeInfo)
   at System.Text.Json.Serialization.JsonCollectionConverter`2.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, TCollection& value)
   at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
   at System.Text.Json.Serialization.Metadata.JsonPropertyInfo`1.ReadJsonAndSetMember(Object obj, ReadStack& state, Utf8JsonReader& reader)
   at System.Text.Json.Serialization.Converters.ObjectDefaultConverter`1.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
   at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
   at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, JsonSerializerOptions options, ReadStack& state)
   at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan`1 utf8Json, JsonTypeInfo jsonTypeInfo, Nullable`1 actualByteCount)
   at System.Text.Json.JsonSerializer.ReadUsingMetadata[TValue](JsonElement element, JsonTypeInfo jsonTypeInfo)
   at System.Text.Json.JsonSerializer.Deserialize[TValue](JsonElement element, JsonSerializerOptions options)
   at Microsoft.Playwright.Helpers.JsonExtensions.ToObject[T](JsonElement element, JsonSerializerOptions options) in /_/src/Playwright/Helpers/JsonExtensions.cs:line 52
   at Microsoft.Playwright.Core.BrowserContext.OnMessage(String method, Nullable`1 serverParams) in /_/src/Playwright/Core/BrowserContext.cs:line 161
   at Microsoft.Playwright.Transport.Connection.Dispatch(PlaywrightServerMessage message) in /_/src/Playwright/Transport/Connection.cs:line 314

I can also confirm that downgrading the package to 1.40.0 or updating the target to .NET 8 both resolve the issue.

[mxschmitt]

@daveaglick thanks, we'll release an update soon - .NET 8 is a great workaround in the meantime.