Fatal Compilation Error: preprocessor directives, not placed on new line

[aabs]

Describe the bug

Getting errors after updating to Microsoft Visual Studio Professional 2022 (64-bit) - Preview
Version 17.13.0 Preview 2.0.

The error messages produced indicate malformed code generation in Vogen:

1>C:\dev\aabs\5th-related\ast-builder\src\ast-model\obj\Debug\net9.0\Vogen\Vogen.ValueObjectGenerator\ast_AssemblyName.g.cs(97,37,97,38): error CS1040: Preprocessor directives must appear as the first non-whitespace character on a line

The original code looks like this:

[ValueObject<string>]
[Instance("anonymous", "", "For things like in-memory assemblies etc")]
public partial struct AssemblyName;

The generated code contains this:

#pragma warning disable CS8767 // Nullability of reference types in type of parameter doesn't match implicitly implemented member because of nullability attributes.

        public static bool TryFrom( #if NETCOREAPP3_0_OR_GREATER
[global::System.Diagnostics.CodeAnalysis.NotNullWhen(true)] 
#endif
        System.String? value, #if NETCOREAPP3_0_OR_GREATER
 [global::System.Diagnostics.CodeAnalysis.MaybeNullWhen(false)] 
#endif
        out AssemblyName vo)
#pragma warning restore CS8767 // Nullability of reference types in type of parameter doesn't match implicitly implemented member because of nullability attributes.

        {
. . . snip
        }

Note the fragment TryFrom( #if NETCOREAPP which is invalid.

Steps to reproduce

Update VS to latest preview (17.13.0 Preview 2.0).
Rebuild the code. Build will fail with the above issue.

I tried updating to the latest version of the Nuget pkg (5.0.6) and restarting VS, but the code generated still broke.

Expected behaviour

The #if should be on a new line. Then all should be fine.

[danielcweber]

Temporary workaround: Fixate the SDK to a working version and disable rollforward in a global.json. This works for me:

{
  "sdk": {
    "version": "9.0.101",
    "rollForward": "disable"
  }
}

[aabs]

thanks for the suggestion. I tried that, and then forced a regeneration (after a VS restart) and the result still contained malformed C#.

[aabs]

I was able to temporarily suppress the generation of the TryFrom and TryParse code by adding the following to my decls, but I'm not sure what the downstream consequences would be.

[ValueObject<uint>
#if VOGEN_IS_BROKEN
    ( parsableForStrings: ParsableForStrings.GenerateNothing, 
      tryFromGeneration: TryFromGeneration.Omit, 
      parsableForPrimitives: ParsableForPrimitives.GenerateNothing )
#endif
]

[nabeelio]

I'm running into the same issue. I put the SDK version back to 9.0.100, and I'll try to keep going backwards. I updated last night, and I think I was on quite an old version.

I tried @aabs suggestion, but that parseableForStrings option would break things (I think, trying it now)

[ValueObject<string>(
    tryFromGeneration: TryFromGeneration.Omit,
    parsableForPrimitives: ParsableForPrimitives.GenerateNothing
)]
public readonly partial struct PirepId;

It's generating:

        /// <summary>
        /// </summary>
        /// <returns>
        /// True if the value passes any validation (after running any optional normalization).
        /// </returns>
        public static global::System.Boolean TryParse(
#if NETCOREAPP3_0_OR_GREATER
[global::System.Diagnostics.CodeAnalysis.NotNullWhen(true)]
#endif
        global::System.String? s, global::System.IFormatProvider? provider,
#if NETCOREAPP3_0_OR_GREATER
[global::System.Diagnostics.CodeAnalysis.MaybeNullWhen(false)]
#endif
 out PirepId result)

[nabeelio]

Damn, looks like only back to 9.0.100 is available.

[nabeelio]

Adding parsableForStrings: ParsableForStrings.GenerateNothing did work, but not sure of the side-effects