After this change, impl Trait existentials are
desugared to a new `abstract type` definition
paired with a set of lifetimes to apply.
In-scope generics are included as parents of the
`abstract type` generics. Parent regions are
replaced with static, and parent regions
referenced in the `impl Trait` type are duplicated
at the end of the `abstract type`'s generics.
Replace hir::TyImplTrait with TyImplTraitUniversal and
TyImplTraitExistential.
Add an ImplTraitContext enum to rustc::hir::lowering to track the kind
and allowedness of an impl Trait.
Significantly alter lowering to thread ImplTraitContext and one other
boolean parameter described below throughought much of lowering.
The other parameter is for tracking if lowering a function is in a trait
impl, as there is not enough information to otherwise know this
information during lowering otherwise.
This change also removes the checks from ast_ty_to_ty for impl trait
allowedness as they are now all taking place in HIR lowering.
rustc_driver: expose a way to override query providers in CompileController.
This API has been a long-time coming and will probably become the main method for custom drivers (that is, binaries other than `rustc` itself that use `librustc_driver`) to adapt the compiler's behavior.
rustdoc: add #[allow(unused)] to every doctest
More information in #45750 - this is behavior that was documented but not actually implemented.
I also reordered how outer attributes are applied to doctests. Previously, attributes from `#![doc(test(attr(...)))]` would be applied *after* attributes from within the test itself, meaning if a doctest tried to override lints that would be set crate-wide, it wouldn't work at all. This gives a better scope of how lints can be applied.
Closes#45750
rustdoc: Fix duplicated impls with generics
The same type can appear multiple times in impls so we need to use a set
to avoid adding it multiple times.
Fixes: #45584
Copy all `AsciiExt` methods to the primitive types directly in order to deprecate it later
**EDIT:** [this PR is ready now](https://github.com/rust-lang/rust/pull/44042#issuecomment-333883548). I edited this post to reflect the current status of discussion, which is (apart from code review) pretty much settled.
---
This is my current progress in order to prepare stabilization of #39658. As discussed there (and in #39659), the idea is to deprecated `AsciiExt` and copy all methods to the type directly. Apparently there isn't really a reason to have those methods in an extension trait¹.
~~This is **work in progress**: copy&pasting code while slightly modifying the documentation isn't the most exciting thing to do. Therefore I wanted to already open this WIP PR after doing basically 1/4 of the job (copying methods to `&[u8]`, `char` and `&str` is still missing) to get some feedback before I continue. Some questions possibly worth discussing:~~
1. ~~Does everyone agree that deprecating `AsciiExt` is a good idea? Does everyone agree with the goal of this PR?~~ => apparently yes
2. ~~Are my changes OK so far? Did I do something wrong?~~
3. ~~The issue of the unstable-attribute is currently set to 0. I would wait until you say "Ok" to the whole thing, then create a tracking issue and then insert the correct issue id. Is that ok?~~
4. ~~I tweaked `eq_ignore_ascii_case()`: it now takes the argument `other: u8` instead of `other: &u8`. The latter was enforced by the trait. Since we're not bound to a trait anymore, we can drop the reference, ok?~~ => I reverted this, because the interface has to match the `AsciiExt` interface exactly.
¹ ~~Could it be that we can't write `impl [u8] {}`? This might be the reason for `AsciiExt`. If that is the case: is there a good reason we can't write such an impl block? What can we do instead?~~ => we couldn't at the time this PR was opened, but Simon made it possible.
/cc @SimonSapin @zackw
We don't want to stabilize them now already. The goal of this set of
commits is just to add inherent methods to the four types. Stabilizing
all of those methods can be done later.
Many AsciiExt imports have become useless thanks to the inherent ascii
methods added in the last commits. These were removed. In some places, I
fully specified the ascii method being called to enforce usage of the
AsciiExt trait. Note that some imports are not removed but tagged with
a `#[cfg(stage0)]` attribute. This is necessary, because certain ascii
methods are not yet available in stage0. All those imports will be
removed later.
Additionally, failing tests were fixed. The test suite should exit
successfully now.
DefaultImpl is a highly confusing name for what we now call auto impls,
as in `impl Send for ..`. The name auto impl is not formally decided
but for sanity anything is better than `DefaultImpl` which refers
neither to `default impl` nor to `impl Default`.
