NullReferenceException when generating OpenAPI document

[khellang]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

When upgrading to .NET 10 RC2, we're getting a NRE when generating the OpenAPI spec:

System.NullReferenceException: Object reference not set to an instance of an object.
   at Microsoft.AspNetCore.OpenApi.Generated.<OpenApiXmlCommentSupport_generated>F7E62C7FD2203B967FCD31756AA54279EC2C453447E3E8D9733B7416CC2CDD1D5__XmlCommentOperationTransformer.TransformAsync(OpenApiOperation operation, OpenApiOperationTransformerContext context, CancellationToken cancellationToken) in D:\Code\bim-platform-service\src\Procore.ApiServices\obj\Debug\net10.0\Microsoft.AspNetCore.OpenApi.SourceGenerators\Microsoft.AspNetCore.OpenApi.SourceGenerators.XmlCommentGenerator\OpenApiXmlCommentSupport.generated.cs:line 463
   at Microsoft.AspNetCore.OpenApi.OpenApiDocumentService.GetOperationsAsync(IGrouping`2 descriptions, OpenApiDocument document, IServiceProvider scopedServiceProvider, IOpenApiOperationTransformer[] operationTransformers, IOpenApiSchemaTransformer[] schemaTransformers, CancellationToken cancellationToken)

I tried debugging the code and it turns out that ModelMetadata is null here:

Could this be because we're using slightly unconventional parameter naming? I.e. we have snake_case_lower API parameter, but conventional camelCase parameter names in the controller:

Expected Behavior

No NullReferenceException 😆

Steps To Reproduce

I'm not entirely sure

Exceptions (if any)

System.NullReferenceException: Object reference not set to an instance of an object.
at Microsoft.AspNetCore.OpenApi.Generated.<OpenApiXmlCommentSupport_generated>F7E62C7FD2203B967FCD31756AA54279EC2C453447E3E8D9733B7416CC2CDD1D5__XmlCommentOperationTransformer.TransformAsync(OpenApiOperation operation, OpenApiOperationTransformerContext context, CancellationToken cancellationToken) in D:\Code\bim-platform-service\src\Procore.ApiServices\obj\Debug\net10.0\Microsoft.AspNetCore.OpenApi.SourceGenerators\Microsoft.AspNetCore.OpenApi.SourceGenerators.XmlCommentGenerator\OpenApiXmlCommentSupport.generated.cs:line 463
at Microsoft.AspNetCore.OpenApi.OpenApiDocumentService.GetOperationsAsync(IGrouping`2 descriptions, OpenApiDocument document, IServiceProvider scopedServiceProvider, IOpenApiOperationTransformer[] operationTransformers, IOpenApiSchemaTransformer[] schemaTransformers, CancellationToken cancellationToken)

.NET Version

10.0.100-rc.2.25502.107

Anything else?

No response

[martincostello]

Looks like this is a duplicate of #63757.

[khellang]

Aaah, thank you! No clue why I couldn't find it 😓