EnableRequestDelegateGenerator by default for PublishTrimmed apps

[eerhardt]

Is there an existing issue for this?

• I have searched the existing issues

Is your feature request related to a problem? Please describe the problem.

Currently ASP.NET apps have the following source generators enabled by default when PublishAot=true:

• EnableRequestDelegateGenerator
• EnableConfigurationBindingGenerator

These source generators are also valuable for PublishTrimmed=true apps that don't use Native AOT because they eliminate trim warnings in your app.

Describe the solution you'd like

We should enable these source generators by default when PublishTrimmed=true. Just like we do for PublishAot.

Additional context

No response

[davidfowl]

YESSSS

[mitchdenny]

This is a pretty big step. We'll probably want to look at this after things like the following edge case: #47339

[davidfowl]

Agreed. It might be worth comparing what breaks outright today without the source generator with trimming on.

@eerhardt does ASP.NET Core do aggressive trimming by default now in .NET 8 (Not partial)? If yes, then it's worth exploring this change. If no, then maybe we shouldn't make this change in .NET 8.

[eerhardt]

does ASP.NET Core do aggressive trimming by default now in .NET 8 (Not partial)?

Not yet. That is being decided with dotnet/sdk#30059.

There are efforts being made to push towards "full" trimming though. The current usage of partial trimming is old/legacy and really only meant for existing Mono-based apps - Blazor WASM, MAUI, etc. @agocke @DamianEdwards and I had a discussion a couple weeks ago about being consistent across defaults, docs, and UI (ex. property page in VS).

Overall, we are trying to get to an understandable and maintainable place with regards to trimming. Using partial trimming and ignoring the trim warnings is not that place.

See also dotnet/runtime#84378

[davidfowl]

We should do this only if TrimMode is full.