Prefix Almost Everything

[ds5678]

Game developers often use the global namespace and external libraries when making their games. For modding, this can cause conflicts during mod development. Although we currently have a way to prefix assemblies and namespaces, it's an opt-in system. An opt-out solution would be better because mod loaders can't anticipate all the assemblies game communities might want to prefix. By prefixing everything but UnityEditor and UnityEngine, we can prevent all potential conflicts between generated interop and managed libraries.

[Kasuromi]

This change seems like it would break current interop assembly usage. It would require everyone to update their code to use the new prefix.

Some games have 100s of assemblies and are constantly growing. If someone wanted to preserve functionality of old code without having to recompile against the new prefix, every assembly will need to be specified and new assemblies will require updates to the mod loader package.

Could we possibly add an opt-in feature for prefixing (or not prefixing) any assemblies but the old ones we had specified?

[ghorsington]

I agree that this will break any code that relies on the current API, but on the other hand, I think that in the long run, this is the correct thing to do.

How about introducing this behaviour as an opt-in for 1.x versions? Specifically

• Allow both include/exclude options. The options will be exclusive, i.e. specifying both is an error.
• By default, apply the current include behaviour on 1.x. Also, emit a warning that includes behaviour will be removed in the next major version

This way, we can at least provide a warning about this while still retaining the current behaviour until the next major release. Mod loaders can then choose what behaviour to use (in the case of BepInEx, we can enable exclusion behaviour right away for our doorstop 4 branch, but inclusion behaviour will be needed for current GTFO mods until they migrate too).

Another option is that I can make a separate next branch into which we'll start adding major breaking changes for the next major 2.x version. I was thinking about making such a branch, but I just didn't since I haven't yet made any major breaking changes.

How about these two options -- which one would be better? Any other opinions on how to integrate this into master or address this being a breaking change are welcome.

[ds5678]

I implemented your requested changes. A couple things of note:

• I had to bump IsExternalInit to 1.0.3. Il2CppInterop.Generator would not compile on netstandard 2.1 otherwise.
• My implementation uses Unity as the only default exclusion prefix.
• Like discussed, this is backwards-compatible. The old options still work.
• The new options are incompatible with the old options, and an exception is thrown when they're used together.

[ds5678]

I just added code to prevent Assembly-CSharp and Assembly-CSharp-firstpass from getting their assembly name changed. No external library can have those names, and it reduces friction in the transition for modders.