They were originally called "opt-in, built-in traits" (OIBITs), but
people realized that the name was too confusing and a mouthful, and so
they were renamed to just "auto traits". The feature flag's name wasn't
updated, though, so that's what this PR does.
There are some other spots in the compiler that still refer to OIBITs,
but I don't think changing those now is worth it since they are internal
and not particularly relevant to this PR.
Also see <https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/opt-in.2C.20built-in.20traits.20(auto.20traits).20feature.20name>.
Remove `Box::leak_with_alloc`
Add leak-test for box with allocator
Rename `AllocErr` to `AllocError` in leak-test
Add `Box::alloc` and adjust examples to use the new API
If a symbol name can only be imported from one place for a type, and
as long as it was not glob-imported anywhere in the current crate, we
can trim its printed path and print only the name.
This has wide implications on error messages with types, for example,
shortening `std::vec::Vec` to just `Vec`, as long as there is no other
`Vec` importable anywhere.
This adds a new '-Z trim-diagnostic-paths=false' option to control this
feature.
On the good path, with no diagnosis printed, we should try to avoid
issuing this query, so we need to prevent trimmed_def_paths query on
several cases.
This change also relies on a previous commit that differentiates
between `Debug` and `Display` on various rustc types, where the latter
is trimmed and presented to the user and the former is not.
Currently, the def span of a funtion encompasses the entire function
signature and body. However, this is usually unnecessarily verbose - when we are
pointing at an entire function in a diagnostic, we almost always want to
point at the signature. The actual contents of the body tends to be
irrelevant to the diagnostic we are emitting, and just takes up
additional screen space.
This commit changes the `def_span` of all function items (freestanding
functions, `impl`-block methods, and `trait`-block methods) to be the
span of the signature. For example, the function
```rust
pub fn foo<T>(val: T) -> T { val }
```
now has a `def_span` corresponding to `pub fn foo<T>(val: T) -> T`
(everything before the opening curly brace).
Trait methods without a body have a `def_span` which includes the
trailing semicolon. For example:
```rust
trait Foo {
fn bar();
}```
the function definition `Foo::bar` has a `def_span` of `fn bar();`
This makes our diagnostic output much shorter, and emphasizes
information that is relevant to whatever diagnostic we are reporting.
We continue to use the full span (including the body) in a few of
places:
* MIR building uses the full span when building source scopes.
* 'Outlives suggestions' use the full span to sort the diagnostics being
emitted.
* The `#[rustc_on_unimplemented(enclosing_scope="in this scope")]`
attribute points the entire scope body.
* The 'unconditional recursion' lint uses the full span to show
additional context for the recursive call.
All of these cases work only with local items, so we don't need to
add anything extra to crate metadata.
This fixes an issue with the following sample:
mod foo {
mod inaccessible {
pub struct X;
}
pub mod avail {
pub struct X;
}
}
fn main() { X; }
Instead of suggesting both `use crate::foo::inaccessible::X;` and `use
crate::foo::avail::X;`, it should only suggest the latter.
It is done by trimming the list of suggestions from inaccessible paths
if accessible paths are present.
Visibility is checked with `is_accessible_from` now instead of being
hard-coded.
-
Some tests fixes are trivial, and others require a bit more explaining,
here are my comments:
src/test/ui/issues/issue-35675.stderr: Only needs to make the enum
public to have the suggestion make sense.
src/test/ui/issues/issue-42944.stderr: Importing the tuple struct won't
help because its constructor is not visible, so the attempted
constructor does not work. In that case, it's better not to suggest it.
The case where the constructor is public is covered in `issue-26545.rs`.
Decouple `rustc_hir::print` into `rustc_hir_pretty`
High level summary:
- The HIR pretty printer, `rustc_hir::print` is moved into a new crate `rustc_hir_pretty`.
- `rustc_ast_pretty` and `rustc_errors` are dropped as `rustc_hir` dependencies.
- The dependence on HIR pretty is generally reduced, leaving `rustc_save_analysis`, `rustdoc`, `rustc_metadata`, and `rustc_driver` as the remaining clients.
The main goal here is to reduce `rustc_hir`'s dependencies and its size such that it can start and finish earlier, thereby working towards https://github.com/rust-lang/rust/issues/65031.
r? @Zoxc
They used to be covered by `optin_builtin_traits` but negative impls
are now applicable to all traits, not just auto traits.
This also adds docs in the unstable book for the current state of auto traits.
Increase verbosity when suggesting subtle code changes
Do not suggest changes that are actually quite small inline, to minimize the likelihood of confusion.
Fix#69243.
Address inconsistency in using "is" with "declared here"
"is" was generally used for NLL diagnostics, but not other diagnostics. Using "is" makes the diagnostics sound more natural and readable, so it seems sensible to commit to them throughout.
r? @Centril
```
error[E0412]: cannot find type `T` in this scope
--> file.rs:3:12
|
3 | impl Trait<T> for Struct {}
| - ^ not found in this scope
| |
| help: you might be missing a type parameter: `<T>`
```
Fix#64298.
The error messages of the two tests effected degraded in quality. The
errors no longer suggest types in other modules as they now assume that
the arguments are const args, not type args.
