Resolve intra-doc links on additional documentation for re-exports in lexical scope
Fixes https://github.com/rust-lang/rust/issues/77254.
- Preserve the parent module of `DocFragment`s
+ Add `parent_module` to `DocFragment`
+ Require the `parent_module` of the item being inlined
+ Preserve the hir_id for ExternCrates so rustdoc can find the parent module later
+ Take an optional `parent_module` for `build_impl` and `merge_attrs`.
Preserve the difference between parent modules for each doc-comment.
+ Support a single additional re-exports in from_ast. Originally this took a vec but I ended up not using it.
+ Don't require the parent_module for all `impl`s, just inlined items
In particular, this will be `None` whenever the attribute is not on a
re-export.
+ Only store the parent_module, not the HirId
When re-exporting a re-export, the HirId is not available. Fortunately,
`collect_intra_doc_links` doesn't actually need all the info from a
HirId, just the parent module.
- Introduce `Divider`
This distinguishes between documentation on the original from docs on the re-export.
- Use the new module information for intra-doc links
+ Make the parent module conditional on whether the docs are on a re-export
+ Make `resolve_link` take `&Item` instead of `&mut Item`
Previously the borrow checker gave an error about multiple mutable
borrows, because `dox` borrowed from `item`.
+ Fix `crate::` for re-exports
`crate` means something different depending on where the attribute
came from.
+ Make it work for `#[doc]` attributes too
This required combining several attributes as one so they would keep
the links.
r? `@GuillaumeGomez`
Implementation of RFC2867
https://github.com/rust-lang/rust/issues/74727
So I've started work on this, I think my next steps are to make use of the `instruction_set` value in the llvm codegen but this is the point where I begin to get a bit lost. I'm looking at the code but it would be nice to have some guidance on what I've currently done and what I'm doing next 😄
Add compile fail test for issue 27675
A recently merged PR (#73905) strengthened the checks on bounds of associated items. This rejects the attack path of #27675 which consisted of constructing a `dyn Trait<Item=T>` where `T` would not fulfill the bounds required on `Item` of the `Trait` behind the dyn object.
This regression test, extracted from [the weaponized instance](https://github.com/rust-lang/rust/issues/27675#issuecomment-696956878), checks that this is rejected.
Upgrade to tracing-subscriber 0.2.13
The primary motivation is to get the changes from
https://github.com/tokio-rs/tracing/pull/990. Example output:
```
$ RUSTDOC_LOG=debug rustdoc +rustc2
warning: some trace filter directives would enable traces that are disabled statically
| `debug` would enable the DEBUG level for all targets
= note: the static max level is `info`
= help: to enable DEBUG logging, remove the `max_level_info` feature
```
r? `@Mark-Simulacrum`
cc `@hawkw` ❤️
- Make the parent module conditional on whether the docs are on a re-export
- Make `resolve_link` take `&Item` instead of `&mut Item`
Previously the borrow checker gave an error about multiple mutable
borrows, because `dox` borrowed from `item`.
- Fix `crate::` for re-exports
`crate` means something different depending on where the attribute
came from.
- Make it work for `#[doc]` attributes too
This required combining several attributes as one so they would keep
the links.
Detect blocks that could be struct expr bodies
This approach lives exclusively in the parser, so struct expr bodies
that are syntactically correct on their own but are otherwise incorrect
will still emit confusing errors, like in the following case:
```rust
fn foo() -> Foo {
bar: Vec::new()
}
```
```
error[E0425]: cannot find value `bar` in this scope
--> src/file.rs:5:5
|
5 | bar: Vec::new()
| ^^^ expecting a type here because of type ascription
error[E0214]: parenthesized type parameters may only be used with a `Fn` trait
--> src/file.rs:5:15
|
5 | bar: Vec::new()
| ^^^^^ only `Fn` traits may use parentheses
error[E0107]: wrong number of type arguments: expected 1, found 0
--> src/file.rs:5:10
|
5 | bar: Vec::new()
| ^^^^^^^^^^ expected 1 type argument
```
If that field had a trailing comma, that would be a parse error and it
would trigger the new, more targetted, error:
```
error: struct literal body without path
--> file.rs:4:17
|
4 | fn foo() -> Foo {
| _________________^
5 | | bar: Vec::new(),
6 | | }
| |_^
|
help: you might have forgotten to add the struct literal inside the block
|
4 | fn foo() -> Foo { Path {
5 | bar: Vec::new(),
6 | } }
|
```
Partially address last remaining part of #34255.
The primary motivation is to get the changes from
https://github.com/tokio-rs/tracing/pull/990. Example output:
```
$ RUSTDOC_LOG=debug rustdoc +rustc2
warning: some trace filter directives would enable traces that are disabled statically
| `debug` would enable the DEBUG level for all targets
= note: the static max level is `info`
= help: to enable DEBUG logging, remove the `max_level_info` feature
```
- Remove useless test
This was testing for an ICE when passing `RUST_LOG=rustc_middle`. I
noticed it because it started giving the tracing warning (because tests
are not run with debug-logging enabled). Since this bug seems unlikely
to re-occur, I just removed it altogether.
This approach lives exclusively in the parser, so struct expr bodies
that are syntactically correct on their own but are otherwise incorrect
will still emit confusing errors, like in the following case:
```rust
fn foo() -> Foo {
bar: Vec::new()
}
```
```
error[E0425]: cannot find value `bar` in this scope
--> src/file.rs:5:5
|
5 | bar: Vec::new()
| ^^^ expecting a type here because of type ascription
error[E0214]: parenthesized type parameters may only be used with a `Fn` trait
--> src/file.rs:5:15
|
5 | bar: Vec::new()
| ^^^^^ only `Fn` traits may use parentheses
error[E0107]: wrong number of type arguments: expected 1, found 0
--> src/file.rs:5:10
|
5 | bar: Vec::new()
| ^^^^^^^^^^ expected 1 type argument
```
If that field had a trailing comma, that would be a parse error and it
would trigger the new, more targetted, error:
```
error: struct literal body without path
--> file.rs:4:17
|
4 | fn foo() -> Foo {
| _________________^
5 | | bar: Vec::new(),
6 | | }
| |_^
|
help: you might have forgotten to add the struct literal inside the block
|
4 | fn foo() -> Foo { Path {
5 | bar: Vec::new(),
6 | } }
|
```
Partially address last part of #34255.
Give `impl Trait` in a `const fn` its own feature gate
...previously it was gated under `#![feature(const_fn)]`.
I think we actually want to do this in all const-contexts? If so, this should be `#![feature(const_impl_trait)]` instead. I don't think there's any way to make use of `impl Trait` within a `const` initializer.
cc #77463
r? `@oli-obk`
Eliminate bounds checking in slice::Windows
This is how `<core::slice::Windows as Iterator>::next` looks right now:
```rust
fn next(&mut self) -> Option<&'a [T]> {
if self.size > self.v.len() {
None
} else {
let ret = Some(&self.v[..self.size]);
self.v = &self.v[1..];
ret
}
}
```
The line with `self.v = &self.v[1..];` relies on assumption that `self.v` is definitely not empty at this point. Else branch is taken when `self.size <= self.v.len()`, so `self.v` can be empty if `self.size` is zero. In practice, since `Windows` is never created directly but rather trough `[T]::windows` which panics when `size` is zero, `self.size` is never zero. However, the compiler doesn't know about this check, so it keeps the code which checks bounds and panics.
Using `NonZeroUsize` lets the compiler know about this invariant and reliably eliminate bounds checking without `unsafe` on `-O2`. Here is assembly of `Windows<'a, u32>::next` before and after this change ([goldbolt](https://godbolt.org/z/xrefzx)):
<details>
<summary>Before</summary>
```
example::next:
push rax
mov rcx, qword ptr [rdi + 8]
mov rdx, qword ptr [rdi + 16]
cmp rdx, rcx
jbe .LBB0_2
xor eax, eax
pop rcx
ret
.LBB0_2:
test rcx, rcx
je .LBB0_5
mov rax, qword ptr [rdi]
mov rsi, rax
add rsi, 4
add rcx, -1
mov qword ptr [rdi], rsi
mov qword ptr [rdi + 8], rcx
pop rcx
ret
.LBB0_5:
lea rdx, [rip + .L__unnamed_1]
mov edi, 1
xor esi, esi
call qword ptr [rip + core::slice::slice_index_order_fail@GOTPCREL]
ud2
.L__unnamed_2:
.ascii "./example.rs"
.L__unnamed_1:
.quad .L__unnamed_2
.asciz "\f\000\000\000\000\000\000\000\016\000\000\000\027\000\000"
```
</details>
<details>
<summary>After</summary>
```
example::next:
mov rcx, qword ptr [rdi + 8]
mov rdx, qword ptr [rdi + 16]
cmp rdx, rcx
jbe .LBB0_2
xor eax, eax
ret
.LBB0_2:
mov rax, qword ptr [rdi]
lea rsi, [rax + 4]
add rcx, -1
mov qword ptr [rdi], rsi
mov qword ptr [rdi + 8], rcx
ret
```
</details>
Note the lack of call to `core::slice::slice_index_order_fail` in second snippet.
#### Possible reasons _not_ to merge this PR:
* this changes the error message on panic in `[T]::windows`. However, AFAIK this messages are not covered by backwards compatibility policy.
resolve: improve "try using the enum's variant"
Fixes#73427.
This PR improves the "try using the enum's variant" suggestion:
- Variants in suggestions would not result in more errors (e.g. use of a struct variant is only suggested if the suggestion can trivially construct that variant). Therefore, suggestions are only emitted for variants that have no fields (since the suggestion can't know what value fields would have).
- Suggestions include the syntax for constructing the variant. If a struct or tuple variant is suggested, then it is constructed in the suggestion - unless in pattern-matching or when arguments are already provided.
- A help message is added which mentions the variants which are no longer suggested.
All of the diagnostic logic introduced by this PR is separated from the normal code path for a successful compilation.
r? `@estebank`
inliner: use caller param_env
We used the callee param env instead of the caller param env by accident in #77430, this PR fixes that and caches it in the `Inliner` struct.
fixes#77564
r? @ecstatic-morse
Only check the own predicates of associated types when confirming
projection candidates.
Also consider implied bounds when comparing trait and impl methods.
Normalizing `<dyn Iterator<Item = ()> as Iterator>::Item` no longer
requires selecting `dyn Iterator<Item = ()>: Iterator`. This was
previously worked around by using a special type-folder to normalize
things.
Bounds of the form `type Future: Future<Result=Self::Result>` exist in
some ecosystem crates. To validate these bounds for trait objects we
need to normalize `Self::Result` in a way that doesn't cause a cycle.
Record `expansion_that_defined` into crate metadata
Fixes#77523
Now that hygiene serialization is implemented, we also need to record
`expansion_that_defined` so that we properly handle a foreign
`SyntaxContext`.
Fix span for unicode escape suggestion.
If a unicode escape is missing the curly braces, the suggested fix is to add the curly braces, but the span for the fix was incorrect. It was not covering the `\u`, but the suggested text includes the `\u`, causing the resulting fix to be `"\u\u{1234}"`. This changes it so that the span includes the `\u`. An alternate fix would be to remove `\u` from the suggested fix, but I think the error message reads better if the entire escape is included.
