Swagger .NET 8 Error

Swashbuckle CLI was able to output schema of my API before, but this time, it throws this error message:

System.InvalidOperationException: A type named 'StartupProduction' or 'Startup' could not be found in assembly

I used top level statement with minimal API on .NET 8 and nothing is changed on that, so I was not able to find anything to do with Startup type.

After I investigate further by commenting line by line, I found out that the issue is on my switch statement.

So it looks like the following:

return config.Section?.Key switch
{
  Value1 => services.AddSingleton<Handler1>(),
  Value2 => services.AddSingleton<Handler2>(),
  _ => throw new InvalidOperationException();
}

Problem is the Section is pulled from appsettings.json and when the CLI runs, it doesn't have value, so it never returned the services object.

Changing the above to the following fixed the issue:

return config.Section == null ? services : config.Section.Key switch
{
  Value1 => services.AddSingleton<Handler1>(),
  Value2 => services.AddSingleton<Handler2>(),
  _ => throw new InvalidOperationException();
}