2479: Add expansion infrastructure for derive macros r=matklad a=flodiebold
I thought I'd experiment a bit with attribute macro/derive expansion, and here's what I've got so far. It has dummy implementations of the Copy / Clone derives, to show that the approach works; it doesn't add any attribute macro support, but I think that fits into the architecture.
Basically, during raw item collection, we look at the attributes and generate macro calls for them if necessary. Currently I only do this for derives, and just add the derive macro calls as separate calls next to the item. I think for derives, it's important that they don't obscure the actual item, since they can't actually change it (e.g. sending the item token tree through macro expansion unnecessarily might make completion within it more complicated).
Attribute macros would have to be recognized at that stage and replace the item (i.e., the raw item collector will just emit an attribute macro call, and not the item). I think when we implement this, we should try to recognize known inert attributes, so that we don't do macro expansion unnecessarily; anything that isn't known needs to be treated as a possible attribute macro call (since the raw item collector can't resolve the macro yet).
There's basically no name resolution for attribute macros implemented, I just hardcoded the built-in derives. In the future, the built-ins should work within the normal name resolution infrastructure; the problem there is that the builtin stubs in `std` use macros 2.0, which we don't support yet (and adding support is outside the scope of this).
One aspect that I don't really have a solution for, but I don't know how important it is, is removing the attribute itself from its input. I'm pretty sure rustc leaves out the attribute macro from the input, but to do that, we'd have to create a completely new syntax node. I guess we could do it when / after converting to a token tree.
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
2474: Move `ModuleSource`, create `ModuleOrigin` r=matklad a=ice1000
As title. This comes right after #2473
Co-authored-by: ice1000 <ice1000kotlin@foxmail.com>
2472: Split up ty tests a bit r=matklad a=flodiebold
`simple` is a bit of a kitchen sink (and not all of them are really about 'simple' features), suggestions for further divisions there are welcome 😄
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
2468: Fix#2467 r=flodiebold a=flodiebold
The stand-alone `unify` requires that the type doesn't contain any type
variables. So we can't share the code here for now (without more refactoring)...
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
The stand-alone `unify` requires that the type doesn't contain any type
variables. So we can't share the code here for now (without more refactoring)...
2465: Extract built-in trait implementations to separate module r=matklad a=flodiebold
This untangles the builtin logic from the Chalk translation.
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
2463: More correct method resolution r=flodiebold a=flodiebold
This should fix the order in which candidates for method resolution are considered, i.e. `(&Foo).clone()` should now be of type `Foo` instead of `&Foo`. It also checks for inherent candidates that the self type unifies properly with the self type in the impl (i.e. `impl Foo<u32>` methods will only be considered for `Foo<u32>`).
To be able to get the correct receiver type to check in the method resolution, I needed the unification logic, so I extracted it to the `unify.rs` module.
Should fix#2435.
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
