A test in F# passes in 16.5.2 but not 16.6.0 Preview 2.1

[vsfeedback]

This issue has been moved from a ticket on Developer Community.

---

[regression] [worked-in:16.5.2]
A test in F# passes in 16.5.2 but not 16.6.0 Preview 2.1.

A minimal failing example is available here: https://github.com/dharmaturtle/objectdumptofile/tree/vstestbug

Specifically: https://github.com/dharmaturtle/objectdumptofile/blob/vstestbug/FSharpTests/Tests.fs

The error thrown is:

System.MissingMethodException : Method not found: ‘Void System.Text.RegularExpressions.Regex…ctor(System.String)’.

The test fails for the Preview version for the native Test Explorer as well as NCrunch, a 3rd party testing plugin. Both work in the VS non-Preview though.

---

Original Comments

Visual Studio Feedback System on 4/7/2020, 02:32 AM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

---

Original Solutions

(no solutions)

[cartermp]

Possibly related:

#8881
#8743

[dharmaturtle]

Here are my SDKs:

C:\Users\dharmaturtle>dotnet --list-sdks
2.1.700 [C:\Program Files\dotnet\sdk]
2.1.800-preview-009696 [C:\Program Files\dotnet\sdk]
2.1.801 [C:\Program Files\dotnet\sdk]
2.2.300 [C:\Program Files\dotnet\sdk]
2.2.400-preview-010219 [C:\Program Files\dotnet\sdk]
2.2.401 [C:\Program Files\dotnet\sdk]
3.0.100 [C:\Program Files\dotnet\sdk]
3.1.201 [C:\Program Files\dotnet\sdk]
3.1.300-preview-015048 [C:\Program Files\dotnet\sdk]

I don't think it's related to .Net 5, unless VS Preview comes with something built in?

[cartermp]

@dharmaturtle It could be related, since the same compiler that ships in a .NET SDK is also present in VS, and this includes .NET 5.

[KevinRansom]

@cartermp, have you been successfull reproducing this issue? It passes fine on my laptop.

[cartermp]

@KevinRansom this requires being on the vstestbug branch. I can confirm it fails on the latest internal dogfood:

Did you run it before you added your fix for the MissingMethodExceptions with type providers?

[KevinRansom]

@brett, okay mate, thanks

[dharmaturtle]

It now passes in VS 16.6.0 Preview 4.0, but I just discovered that it fails at run time in v16.5.4 despite tests passing 🙄

Oh well, I'll assume that whatever broke between 16.5.2 and 16.5.4 got fixed with #8971. Thanks peeps!

Edit: aaaand I can't close this issue cause the bot created it >_>