Improve diagnostics for function passed when a type was expected.
This PR improves diagnostics, it provides more information when a function is passed where a type is expected.
r? `@lcnr`
Handle pretty printing of `else if let` clauses without ICEing
When pretty printing the HIR of `if ... {} else if let ... {}` clauses, this displays it the `else if let` part as `match` it gets desugared to, the same way normal `if let` statements are currently displayed, instead of ICEing.
```rust
pub fn main() {
if true {
// 1
} else if let a = 1 {
// 2
} else {
// 3
}
}
```
now gets desugared (via `rustc -Zunpretty=hir,typed src/x.rs`) to:
```rust
#[prelude_import]
use ::std::prelude::rust_2015::*;
#[macro_use]
extern crate std;
pub fn main() ({
(if (true as bool)
({
// 1
} as
()) else {match (1 as i32) {
a => {
// 2
}
_ => {
// 3
}
}} as ())
} as ())
```
For comparison, this code gets HIR prettyprinted the same way before and after this change:
```rust
pub fn main() {
if let a = 1 {
// 2
} else {
// 3
}
}
```
turns into
```rust
#[prelude_import]
use ::std::prelude::rust_2015::*;
#[macro_use]
extern crate std;
pub fn main() ({
(match (1 as i32) {
a => {
// 2
}
_ => {
// 3
}
} as ())
} as ())
```
This closes#82329. It closes#84434 as well, due to having the same root cause.
Give a better error when `std` or `core` are missing
- Suggest using `rustup target add` if `RUSTUP_HOME` is set. I don't know if there's any precedent for doing this, but it seems harmless enough and it will be a big help.
- On nightly, suggest using `cargo build -Z build-std` if `CARGO` is set
- Add a note about `#![no_std]` if `std` is missing but not core
- Add a note that std may be unsupported if `std` is missing but not core
Fixes https://github.com/rust-lang/rust/issues/84418.
r? `@petrochenkov`
- Suggest using `rustup target add` if `RUSTUP_HOME` is set. I don't know if there's any precedent for doing this, but it seems harmless enough and it will be a big help.
- Add a note about `#![no_std]` if `std` is missing but not core
- On nightly, suggest using `cargo build -Z build-std` if `CARGO` is set
- Add a note that std may be unsupported if `std` is missing but not core
- Don't suggest `#![no_std]` when the load isn't injected by the
compiler
various const parameter defaults improvements
Actually resolve names in const parameter defaults, fixing `struct Foo<const N: usize = { usize::MAX }>`.
---
Split generic parameter ban rib for types and consts, allowing
```rust
#![feature(const_generics_defaults)]
struct Q;
struct Foo<T = Q, const Q: usize = 3>(T);
```
---
Remove the type/const ordering restriction if `const_generics_defaults` is active, even if `const_generics` is not. allowing us to stabilize and test const param defaults separately.
---
Check well formedness of const parameter defaults, eagerly emitting an error for `struct Foo<const N: usize = { 0 - 1 }>`
---
Do not forbid const parameters in param defaults, allowing `struct Foo<const N: usize, T = [u8; N]>(T)` and `struct Foo<const N: usize, const M: usize = N>`. Note that this should not change anything which is stabilized, as on stable, type parameters must be in front of const parameters, which means that type parameter defaults are only allowed if no const parameters exist.
We still forbid generic parameters inside of const param types.
r? `@varkor` `@petrochenkov`
move core::hint::black_box under its own feature gate
The `black_box` function had its own RFC and is tracked separately from the `test` feature at https://github.com/rust-lang/rust/issues/64102. Let's reflect this in the feature gate.
To avoid breaking all the benchmarks, libtest's `test::black_box` is a wrapping definition, not a reexport -- this means it is still under the `test` feature gate.
Cautiously add IntoIterator for arrays by value
Add the attribute described in #84133, `#[rustc_skip_array_during_method_dispatch]`, which effectively hides a trait from method dispatch when the receiver type is an array.
Then cherry-pick `IntoIterator for [T; N]` from #65819 and gate it with that attribute. Arrays can now be used as `IntoIterator` normally, but `array.into_iter()` has edition-dependent behavior, returning `slice::Iter` for 2015 and 2018 editions, or `array::IntoIter` for 2021 and later.
r? `@nikomatsakis`
cc `@LukasKalbertodt` `@rust-lang/libs`
Rework `init` and `cleanup`
This PR reworks the code in `std` that runs before and after `main` and centralizes this code respectively in the functions `init` and `cleanup` in both `sys_common` and `sys`. This makes is easy to see what code is executed during initialization and cleanup on each platform just by looking at e.g. `sys::windows::init`.
Full list of changes:
- new module `rt` in `sys_common` to contain `init` and `cleanup` and the runtime macros.
- `at_exit` and the mechanism to register exit handlers has been completely removed. In practice this was only used for closing sockets on windows and flushing stdout, which have been moved to `cleanup`.
- <s>On windows `alloc` and `net` initialization is now done in `init`, this saves a runtime check in every allocation and network use.</s>
Calculate `span` info on-demand
- Add helper `attr_span` for common reused function
- Stop storing `Span`s on `Item` directly; calculate them on demand instead
- Special case modules, which have different spans depending on whether
you use inner or outer attributes
- Special case impls with fake IDs, which can have either dummy spans (for auto traits) or the DefId of the impl block (for blanket impls)
- Use a fake ID for primitives instead of the ID of the crate; this lets
`source()` know that it should use a dummy span instead of the span of
the crate.
This shrinks `Item` from 48 to 40 bytes.
Helps with https://github.com/rust-lang/rust/issues/76382.
further split up const_fn feature flag
This continues the work on splitting up `const_fn` into separate feature flags:
* `const_fn_trait_bound` for `const fn` with trait bounds
* `const_fn_unsize` for unsizing coercions in `const fn` (looks like only `dyn` unsizing is still guarded here)
I don't know if there are even any things left that `const_fn` guards... at least libcore and liballoc do not need it any more.
`@oli-obk` are you currently able to do reviews?
Revert "rustdoc: Hide `#text` in doc-tests"
See discussion in #84502 - I'm worried that #84445 may cause a lot of breakages if this were to hit stable, so I think it's safer to revert and work on the known correct fix#84478.
Rollup of 8 pull requests
Successful merges:
- #83519 (Implement a lint that highlights all moves larger than a configured limit)
- #84105 (stabilize `core::array::{from_ref,from_mut}` in `1.53.0`)
- #84179 (Explicitly implement `!Send` and `!Sync` for `sys::{Args, Env}`)
- #84427 (Update Clippy)
- #84459 (rustdoc: Turn `JsonRenderer::mod_item_in` into `unreachable!()`)
- #84460 (rustdoc: Remove unnecessary `is_crate` field from doctree::Module and clean::Module)
- #84464 (rustdoc: Get rid of `clean::TypeKind`)
- #84518 (Clean up DOM strings)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
rustdoc: Remove unnecessary `is_crate` field from doctree::Module and clean::Module
It can be calculated on-demand even without a TyCtxt.
This also changed `json::conversions::from_item_kind` to take a whole item, which avoids
having to add more and more parameters.
Helps with https://github.com/rust-lang/rust/issues/76382.
r? ```@camelid```
rustdoc: Turn `JsonRenderer::mod_item_in` into `unreachable!()`
The JSON renderer no longer gets called on modules (since https://github.com/rust-lang/rust/pull/83055).
r? ``@aDotInTheVoid``
Explicitly implement `!Send` and `!Sync` for `sys::{Args, Env}`
Remove the field `_dont_send_or_sync_me: PhantomData<*mut ()>` in favor of an explicit implementation of `!Send` and `!Sync`.
Implement a lint that highlights all moves larger than a configured limit
Tracking issue: #83518
[MCP 420](https://github.com/rust-lang/compiler-team/issues/420) still ~blazing~ in progress
r? ```@pnkfelix```
The main open issue I see with this minimal impl of the feature is that the lint is immediately "stable" (so it can be named on stable), even if it is never executed on stable. I don't think we have the concept of unstable lint names or hiding lint names without an active feature gate, so that would be a bigger change.
Rollup of 10 pull requests
Successful merges:
- #83990 (implement `TrustedRandomAccess` for `Take` iterator adapter)
- #84250 (bootstrap: use bash on illumos to run install scripts)
- #84320 (Use details tag for trait implementors.)
- #84436 (Make a few functions private)
- #84453 (Document From implementations for Waker and RawWaker)
- #84458 (Remove unnecessary fields and parameters in rustdoc)
- #84485 (Add some associated type bounds tests)
- #84489 (Mention FusedIterator case in Iterator::fuse doc)
- #84492 (rustdoc: Remove unnecessary dummy span)
- #84496 (Add some specialization tests)
Failed merges:
r? `@ghost`
`@rustbot` modify labels: rollup
Mention FusedIterator case in Iterator::fuse doc
Using `fuse` on an iterator that incorrectly implements
`FusedIterator` does not fuse the iterator. This commit adds a
note about this in the documentation of this method to increase
awareness about this potential issue (esp. when relying on fuse
in unsafe code).
Closes#83969