Inaccurate error in anonymous record copy-and-update

[kerams]

Repro steps

let t3 (t1: {| gu: string; ff: int |}) = { t1 with ff = 3 }

or sharplab.

Expected behavior

Error saying brace-pipes are required.

Actual behavior

Squiggly under ff with The record label 'ff' is not defined..

Related information

• VSIX for F# built from main
• VS 17.6 Preview 1

[edgarfgp]

I tried fixing this on #15598 and quickly realized there seemed to be an unexpected internal error while executing the following test. Which blocks any further attempt to improve the error reporting on anonymous records :(

Unexpected exception raised in compiler: destAppTy (Failure)

 [<Fact>]
     let ``This expression was expected to have an anonymous Record but has a record`` () =
         Fsx """
 let t3 (t1: {| gu: string; ff: int |}) = { t1 with ff = 3 }
         """
         |> ignoreWarnings
         |> typecheck
         |> shouldFail

System.AggregateException: One or more errors occurred. (One or more errors occurred. (Unknown exception seen in compiler: JetBrains.ReSharper.TestRun...

System.AggregateException
One or more errors occurred. (One or more errors occurred. (Unknown exception seen in compiler: JetBrains.ReSharper.TestRunner.Logging.TraceListener+AssertionException: Unknown exception seen in compiler: JetBrains.ReSharper.TestRunner.Logging.TraceListener+AssertionException: Unknown exception seen in compiler: JetBrains.ReSharper.TestRunner.Logging.TraceListener+AssertionException: Unknown exception seen in compiler: JetBrains.ReSharper.TestRunner.Logging.TraceListener+AssertionException: Unknown exception seen in compiler: JetBrains.ReSharper.TestRunner.Logging.TraceListener+AssertionException: Unknown exception seen in compiler: JetBrains.ReSharper.TestRunner.Logging.TraceListener+AssertionException: Unexpected exception raised in compiler: destAppTy (Failure)

@abonie Does this ring a bell based on #15519 ?

[abonie]

Hmm... I don't expect these are related

[KevinRansom]

This was introduced by this PR: #15214

[auduchinok]

This was introduced by this PR: #15214

@KevinRansom That sounds suspicious, because #15214 was merged in May, and I can reproduce this problem using .NET SDK 6.0.100 which was released in November 2021 and in .NET SDK 7.0.101.

eugene@Eugenes-Air:ConsoleApp30$ dotnet --version
6.0.100

eugene@Eugenes-Air:ConsoleApp30$ dotnet build
Microsoft (R) Build Engine version 17.0.0+c9eb9dd64 for .NET
Copyright (C) Microsoft Corporation. All rights reserved.

  Determining projects to restore...
  Restored /Users/eugene/RiderProjects/ConsoleApp30/ConsoleApp30/ConsoleApp30.fsproj (in 158 ms).
/Users/eugene/RiderProjects/ConsoleApp30/ConsoleApp30/Program.fs(2,52): error FS0039: The record label 'ff' is not defined. [/Users/eugene/RiderProjects/ConsoleApp30/ConsoleApp30/ConsoleApp30.fsproj]

Build FAILED.

/Users/eugene/RiderProjects/ConsoleApp30/ConsoleApp30/Program.fs(2,52): error FS0039: The record label 'ff' is not defined. [/Users/eugene/RiderProjects/ConsoleApp30/ConsoleApp30/ConsoleApp30.fsproj]
    0 Warning(s)
    1 Error(s)

Time Elapsed 00:00:01.66

I didn't try it on other versions.

[auduchinok]

Off-topic: I wonder if we could enable the normal record syntax for anon records too?

RFC says this:

Unlike records, we do not assume that the origExpr has the same type as the overall expression.

For some reason I thought it was already allowed, and when the normal record syntax is used, an anonymous record of the same type would be produced.