7970: Fix incorrect diagnostics for failing built in macros r=jonas-schievink a=brandondong
**Reproduction:**
1. Use a built in macro in such a way that rust-analyzer fails to expand it. For example:
**lib.rs**
```
include!("<valid file but without a .rs extension so it is not indexed by rust-analyzer>");
```
2. rust-analyzer highlights the macro call and says the macro itself cannot be resolved even though include! is in the standard library (unresolved-macro-call diagnostic).
3. No macro-error diagnostic is raised.
**Root cause for incorrect unresolved-macro-call diagnostic:**
1. collector:collect_macro_call is able to resolve include! in legacy scope but the expansion fails. Therefore, it's pushed into unexpanded_macros to be retried with module scope.
2. include! fails at the resolution step in collector:resolve_macros now that it's using module scope. Therefore, it's retained in unexpanded_macros.
3. Finally, collector:finish tries resolving the remaining unexpanded macros but only with module scope. include! again fails at the resolution step so a diagnostic is created.
**Root cause for missing macro-error diagnostic:**
1. In collector:resolve_macros, directive.legacy is None since eager expansion failed in collector:collect_macro_call. The macro_call_as_call_id fails to resolve since we're retrying in module scope. Therefore, collect_macro_expansion is not called for the macro and no macro-error diagnostic is generated.
**Fix:**
- In collector:collect_macro_call, do not add failing built-in macros to the unexpanded_macros list and immediately raise the macro-error diagnostic. This is in contrast to lazy macros which are resolved in collector::resolve_macros and later expanded in collect_macro_expansion where a macro-error diagnostic may be raised.
Co-authored-by: Brandon <brandondong604@hotmail.com>
Co-authored-by: brandondong <brandondong604@hotmail.com>
7778: Fix lowering trailing self paths in UseTrees r=Veykril a=Veykril
Noticed that hovering over `self` in a use tree like `use foo::bar::{self}` showing documentation and such for the current module instead of `bar`.
Co-authored-by: Lukas Wirth <lukastw97@gmail.com>
7804: Introduce TypeCtor::Scalar r=lnicola a=Veykril
`TypeCtor::Int(..) | TypeCtor::Float(..) | TypeCtor::Char | TypeCtor::Bool` => `TypeCtor::Scalar(..)`, in this case we can actually just straight up use `chalk_ir::Scalar` already since its just a POD without any IDs or anything.
Co-authored-by: Lukas Wirth <lukastw97@gmail.com>
