Conditional breakpoint fails to evaluate a string property

[dubeg]

Environment data

dotnet --info output:
.NET Core SDK (reflecting any global.json):
Version: 2.1.403
Commit: 04e15494b6

Runtime Environment:
OS Name: Windows
OS Version: 10.0.17134
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\2.1.403\

Host (useful for support):
Version: 2.1.5
Commit: 290303f510

.NET Core SDKs installed:
2.1.403 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
Microsoft.AspNetCore.All 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 2.1.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]

VS Code version: 1.29.0
C# Extension version: 1.17.0

Steps to reproduce

• Add a conditional breakpoint evaluating a string property of an instance.
• Start a debug session and hit the breakpoint.

Expected behavior

The conditional breakpoint works.

Actual behavior

There's an error in the debug console, and the breakpoint is hit regardless of the condition.

The condition for a breakpoint failed to execute. The condition was 'item.No == "xxx"'. The error returned was 'Evaluation of method System.String.op_Equality() calls into native method System.Environment.FailFast(). Evaluation of native methods in this context is not supported.'.

Additional notes

I tried finding a similar issue in this repo, but I couldn't find any. However, I found this issue which is filed under Visual Studio 2017 15.8, which I have installed (v15.8.9 to be specific).

Could it be that my VS 2017 15.8's debugger takes precedence over the debugger of Omnisharp? Is there a way to tell Omnisharp to use the one it's included with?

[gregg-miskelly]

The C# debugger backend is mostly shared between VS and VS Code. So you are just running into the same bug in both debuggers.

[dubeg]

@gregg-miskelly Oh! Okay. And I guess there's no way to downgrade the version of the debugger.

Also, just noticed that it doesn't always fail. It seems the conditions are very specific.
Here's a minimum repro. The conditional breakpoint is on the Console.Write(str) line.

using System;
using System.Collections.Generic;

namespace test
{
    class Program
    {
        static void Main(string[] args)
        {
            // var str = "AAAAAAAAA"; // Works
            var str = "AAAAAAAA1"; // Fails
            // Expression: str == "AAAAAAAAA"
            Console.Write(str);
        }
    }
}

The condition for a breakpoint failed to execute. The condition was 'str == "AAAAAAAAA"'. The error returned was 'Evaluation of method System.String.op_Equality() calls into native method System.CLRConfig.GetConfigBoolValue(). Evaluation of native methods in this context is not supported.'.

[gregg-miskelly]

Note for anyone reading this, here are the two VS Feedback tickets that also reference the same underlying issue:

• https://developercommunity.visualstudio.com/content/problem/383554/debugger-error-when-comparing-strings-net-core.html
• https://developercommunity.visualstudio.com/content/problem/314822/the-condition-for-a-breakpoint-failed-to-execute-e.html -- not everyone reporting through this ticket is running into this for .NET Core strings, but some certainly are

[gregg-miskelly]

This is now fixed in 1.18.

[ddobric]

Sorry, still have the same issue:

Microsoft Visual Studio Enterprise 2019
Version 16.4.5

[JoeRobich]

Hi @ddobric, You can report Visual Studio issues using "Send Feedback" from the top right corner of Visual Studio. This repository is strictly for the C# extension for VS Code.