Commit Graph

14348 Commits

Author SHA1 Message Date
bors
3fb7e441ae Auto merge of #120370 - x17jiri:likely_unlikely_fix, r=saethlin
Likely unlikely fix

RFC 1131 ( https://github.com/rust-lang/rust/issues/26179 ) added likely/unlikely intrinsics, but they have been broken for a while: https://github.com/rust-lang/rust/issues/96276 , https://github.com/rust-lang/rust/issues/96275 , https://github.com/rust-lang/rust/issues/88767 . This PR tries to fix them.

Changes:
- added a new `cold_path()` intrinsic
- `likely()` and `unlikely()` changed to regular functions implemented using `cold_path()`
2024-11-17 23:57:53 +00:00
bors
5ec7d6eee7 Auto merge of #132646 - jieyouxu:liberate-aarch64-gnu-debug, r=Kobzol
Liberate `aarch64-gnu-debug` from the shackles of `--test-args=clang`

### Changes

- Drop `--test-args=clang` from `aarch64-gnu-debug` so run-make tests that are `//@ needs-force-clang-based-tests` no longer only run if their test name contains `clang` (which is a very cool footgun).
- Reorganize run-make-suport library slightly to accommodate a raw gcc invocation.
- Fix `tests/run-make/mte-ffi/rmake.rs` to use `gcc` instead of *a* c compiler.

try-job: aarch64-gnu
try-job: aarch64-gnu-debug
2024-11-17 20:51:52 +00:00
Jiri Bobek
777003ae9f Likely unlikely fix 2024-11-17 21:49:10 +01:00
许杰友 Jieyou Xu (Joe)
af1c8be400
Rollup merge of #133116 - RalfJung:const-null-ptr, r=dtolnay
stabilize const_ptr_is_null

FCP passed in https://github.com/rust-lang/rust/issues/74939.

The second commit cleans up const stability around UB checks a bit, now that everything they need (except for `const_eval_select`) is stable.

Fixes https://github.com/rust-lang/rust/issues/74939
2024-11-17 23:56:10 +08:00
许杰友 Jieyou Xu (Joe)
ccc3f862d6
Rollup merge of #133093 - est31:let_chains_tests, r=traviscross
Let chains tests

Filing this as this marks off two of the open issues in #132833:

* extending the tests for `move-guard-if-let-chain.rs` and `conflicting_bindings.rs` to have chains with multiple let's (one implementation could for example search for the first `let` and then terminate).
* An instance where a temporary lives shorter than with nested ifs, breaking compilation: #103476. This was fixed in the end by the if let rescoping work.

Closes #103476
2024-11-17 23:56:10 +08:00
许杰友 Jieyou Xu (Joe)
0b157e88d7
Rollup merge of #133060 - tyrone-wu:removelet-span-suggestion, r=jieyouxu
Trim whitespace in RemoveLet primary span

Separate `RemoveLet` span into primary span for `let` and removal suggestion span for `let `, so that primary span does not include whitespace.

Fixes: #133031
2024-11-17 23:56:09 +08:00
许杰友 Jieyou Xu (Joe)
2f62fd3d13
Rollup merge of #133051 - estebank:cond-misparse, r=jieyouxu
Increase accuracy of `if` condition misparse suggestion

Fix #132656.

Look at the expression that was parsed when trying to recover from a bad `if` condition to determine what was likely intended by the user beyond "maybe this was meant to be an `else` body".

```
error: expected `{`, found `map`
  --> $DIR/missing-dot-on-if-condition-expression-fixable.rs:4:30
   |
LL |     for _ in [1, 2, 3].iter()map(|x| x) {}
   |                              ^^^ expected `{`
   |
help: you might have meant to write a method call
   |
LL |     for _ in [1, 2, 3].iter().map(|x| x) {}
   |                              +
```

If a macro statement has been parsed after `else`, suggest a missing `if`:

```
error: expected `{`, found `falsy`
  --> $DIR/else-no-if.rs:47:12
   |
LL |     } else falsy! {} {
   |       ---- ^^^^^
   |       |
   |       expected an `if` or a block after this `else`
   |
help: add an `if` if this is the condition of a chained `else if` statement
   |
LL |     } else if falsy! {} {
   |            ++
```
2024-11-17 23:56:08 +08:00
bors
1e0df74445 Auto merge of #133120 - matthiaskrgr:rollup-4actosy, r=matthiaskrgr
Rollup of 7 pull requests

Successful merges:

 - #131717 (Stabilize `const_atomic_from_ptr`)
 - #132134 (Remove `ResultsVisitable`)
 - #132449 (mark is_val_statically_known intrinsic as stably const-callable)
 - #132569 (rustdoc search: allow queries to end in an empty path segment)
 - #132787 (Unify FnKind between AST visitors and make WalkItemKind more straight forward)
 - #132832 (Deny capturing late-bound ty/const params in nested opaques)
 - #133097 (Opt out TaKO8Ki from review rotation for now)

r? `@ghost`
`@rustbot` modify labels: rollup
2024-11-17 09:45:48 +00:00
Ralf Jung
5eef5ee38a stabilize const_ptr_is_null 2024-11-16 22:50:22 +01:00
Jieyou Xu
dccb6c0f27 Mark numeric-types.rs as 64-bit only for now
This is to unblock the tree, a proper fix will need to be investigated.
I think the debuginfo test suite supports revisions, however debugger
directives do not respect such revisions, which is problematic.

It's that 32-bit and 64-bit msvc of course have different integer widths
for `isize` and `usize`, meaning their underlying integer is different
and thus printed differently.
2024-11-17 04:16:59 +08:00
Matthias Krüger
a1c98ca160
Rollup merge of #132832 - compiler-errors:late-ty, r=cjgillot
Deny capturing late-bound ty/const params in nested opaques

First, this reverts a7f609504c. I can't exactly remember why I approved this specific bit of https://github.com/rust-lang/rust/pull/132466; specifically, I don't know that the purpose of that commit is, and afaict we will never have an opaque that captures late-bound params through a const because opaques can't be used inside of anon consts. Am I missing something `@cjgillot?` Since I can't see a case where this matters, and no tests seem to fail.

The second commit adds a `deny_late_regions: bool` to distinguish `Scope::LateBoundary` which should deny *any* late-bound params or just ty/consts. Then, when resolving opaques we wrap ourselves in a `Scope::LateBoundary { deny_late_regions: false }` so that we deny late-bound ty/const, which fixes a bunch of ICEs that all vaguely look like `impl for<T> Trait<Assoc = impl OtherTrait<T>>`.

I guess this could be achieved other ways; for example, with a different scope kind, or maybe we could just reuse `Scope::Opaque`. But this seems a bit more verbose. I'm open to feedback anyways.

Fixes #131535
Fixes #131637
Fixes #132530

I opted to remove those crashes tests ^ without adding them as regular tests, since they're basically triggering uninteresting late-bound ICEs far off in the trait solver, and the reason that existing tests such as `tests/ui/type-alias-impl-trait/non-lifetime-binder-in-constraint.rs` don't ICE are kinda just coincidental (i.e. due to a missing impl block). I don't really feel motivated to add random permutations to tests just to exercise non-lifetime binders.

r? cjgillot
2024-11-16 21:05:46 +01:00
Matthias Krüger
eff2b7017d
Rollup merge of #132569 - lolbinarycat:rustdoc-search-path-end-empty-v2, r=notriddle
rustdoc search: allow queries to end in an empty path segment

fixes https://github.com/rust-lang/rust/issues/129707

this can be used to show all items in a module,
or all associated items for a type.
currently sufferes slightly due to case insensitivity, so `Option::` will also show items in the `option::` module.

it disables the checking of the last path element, otherwise only items with short names will be shown

r? `@notriddle`
2024-11-16 21:05:45 +01:00
Matthias Krüger
fb5bd7ffcc
Rollup merge of #132449 - RalfJung:is_val_statically_known, r=compiler-errors
mark is_val_statically_known intrinsic as stably const-callable

The intrinsic doesn't actually "do" anything in terms of language semantics, and we are already using it in stable const fn. So let's just properly mark it as stably const-callable to avoid needing `rustc_allow_const_fn_unstable` (and thus reducing noise and keeping the remaining `rustc_allow_const_fn_unstable` as a more clear signal).

Cc `@rust-lang/lang` usually you have to approve exposing intrinsics in const, but this intrinsic is basically just a compiler implementation detail. So FCP doesn't seem necessary.
Cc `@rust-lang/wg-const-eval`
2024-11-16 21:05:44 +01:00
Esteban Küber
c09c73b996 Reword suggestion message 2024-11-16 20:03:31 +00:00
Esteban Küber
629a69f3e2 Better account for else if macro conditions mising an if
If a macro statement has been parsed after `else`, suggest a missing `if`:

```
error: expected `{`, found `falsy`
  --> $DIR/else-no-if.rs:47:12
   |
LL |     } else falsy! {} {
   |       ---- ^^^^^
   |       |
   |       expected an `if` or a block after this `else`
   |
help: add an `if` if this is the condition of a chained `else if` statement
   |
LL |     } else if falsy! {} {
   |            ++
```
2024-11-16 20:03:31 +00:00
Esteban Küber
04fe839177 Increase accuracy of if condition misparse suggestion
Look at the expression that was parsed when trying to recover from a bad `if` condition to determine what was likely intended by the user beyond "maybe this was meant to be an `else` body".

```
error: expected `{`, found `map`
  --> $DIR/missing-dot-on-if-condition-expression-fixable.rs:4:30
   |
LL |     for _ in [1, 2, 3].iter()map(|x| x) {}
   |                              ^^^ expected `{`
   |
help: you might have meant to write a method call
   |
LL |     for _ in [1, 2, 3].iter().map(|x| x) {}
   |                              +
```
2024-11-16 20:03:31 +00:00
Jieyou Xu
e70df0909a Update cdb annotations for unit-type.rs with cdb 10.0.26100.2161 2024-11-17 00:50:54 +08:00
Jieyou Xu
94f3dcf601 Update cdb annotations for range-types.rs with cdb 10.0.26100.2161 2024-11-17 00:42:30 +08:00
Jieyou Xu
1503279593 Update cdb annotations for numeric-types with cdb 10.0.26100.2161 2024-11-17 00:33:40 +08:00
bors
46e8d20301 Auto merge of #130443 - veluca93:legacy-const-generics-fix, r=BoxyUwU
Fix ICE when passing DefId-creating args to legacy_const_generics.

r? BoxyUwU

Fixes #123077
Fixes #129150
2024-11-16 04:57:15 +00:00
est31
f502dcea38 Add regression test for issue #103476, fixed in edition 2024 2024-11-16 05:21:09 +01:00
est31
427d9152d2 Also check if let chains with multiple lets in these two tests 2024-11-16 05:01:52 +01:00
Luca Versari
b462c68aee Fix ICE when passing DefId-creating args to legacy_const_generics. 2024-11-16 01:07:51 +01:00
Guillaume Gomez
fc8d2b38d8
Rollup merge of #133080 - ehuss:edition-desugar-span, r=compiler-errors
Fix span edition for 2024 RPIT coming from an external macro

This fixes a problem where code generated by an external macro with an RPIT would end up using the call-site edition instead of the macro's edition for the RPIT. When used from a 2024 crate, this caused the code to change behavior to the 2024 capturing rules, which we don't want.

This was caused by the impl-trait lowering code would replace the span with one marked with `DesugaringKind::OpaqueTy` desugaring. However, it was also overriding the edition of the span with the edition of the local crate. Instead it should be using the edition of the span itself.

Fixes https://github.com/rust-lang/rust/issues/132917
2024-11-15 23:38:12 +01:00
Guillaume Gomez
c3a632c28b
Rollup merge of #133074 - ferrocene:ja-make-ui-test-os-agnostic, r=Noratrieb
make UI test OS-agnostic

the internal representation of `std::sync::Mutex` depends on the compilation target. due to this, the compiler produces different number of errors for UI test `issue-17431-6.rs` depending on the compilation target.

for example, when compiling the UI test to an `*-apple-*` or `*-qnx7*` target, the "cycle detected" error is not reported

``` console
$ cat src/lib.rs
use std::sync::Mutex;

enum Foo {
    X(Mutex<Option<Foo>>),
}

impl Foo {
    fn bar(self) {}
}

fn main() {}

$ cargo check --target x86_64-apple-ios 2>&1 | rg '^error\['
error[E0072]: recursive type `Foo` has infinite size
```

whereas rustc produces two errors for other OSes, like Linux, which is what the UI test expects

``` console
$ cargo check --target x86_64-unknown-linux-gnu 2>&1 | rg '^error\['
error[E0072]: recursive type `Foo` has infinite size
error[E0391]: cycle detected when computing when `Foo` needs drop
```

this commit replaces the problematic `Mutex` with `UnsafeCell`, which has the same internal representation regardless of the compilation target. with that change, rustc reports two errors for all compilation targets.

``` console
$ cat src/lib.rs
use std::cell::UnsafeCell;

enum Foo {
    X(UnsafeCell<Option<Foo>>),
}

impl Foo {
    fn bar(self) {}
}

fn main() {}

$ cargo check --target x86_64-apple-ios 2>&1 | rg '^error\['
error[E0072]: recursive type `Foo` has infinite size
error[E0391]: cycle detected when computing when `Foo` needs drop
```

with this change, we can remove the `ignore-apple` directive as the UI test now also passes on apple targets.
2024-11-15 23:38:11 +01:00
Guillaume Gomez
b3e2981ff7
Rollup merge of #132978 - WaffleLapkin:very-semantic-change-kind, r=compiler-errors
Mention both release *and* edition breakage for never type lints

This PR makes ~~two changes~~ a change to the never type lints (`dependency_on_unit_never_type_fallback` and `never_type_fallback_flowing_into_unsafe`):
1.  Change the wording of the note to mention that the breaking change will be made in an edition _and_ in a future release
2. ~~Make these warnings be reported in deps (hopefully the lints are matured enough)~~

r? ``@compiler-errors``
cc ``@ehuss``
closes #132930
2024-11-15 23:38:10 +01:00
Guillaume Gomez
1f83a4de1f
Rollup merge of #132936 - surechen:fix_131989, r=Nadrieril
For expr `return (_ = 42);` unused_paren lint should not be triggered

fixes #131989
2024-11-15 23:38:09 +01:00
binarycat
cd46ff6c05 rustdoc search: allow queries to end in an empty path segment
fixes https://github.com/rust-lang/rust/issues/129707

this can be used to show all items in a module,
or all associated items for a type.
currently sufferes slightly due to case insensitivity,
so `Option::` will also show items in the `option::` module.

it disables the checking of the last path element,
otherwise only items with short names will be shown
2024-11-15 16:32:40 -06:00
bors
917a50a039 Auto merge of #133079 - matthiaskrgr:rollup-k8u7syk, r=matthiaskrgr
Rollup of 4 pull requests

Successful merges:

 - #132817 (Recurse into APITs in `impl_trait_overcaptures`)
 - #133021 (Refactor `configure_annotatable`)
 - #133045 (tests: Test pac-ret flag merging on clang with LTO)
 - #133049 (Change Visitor::visit_precise_capturing_arg so it returns a Visitor::Result)

r? `@ghost`
`@rustbot` modify labels: rollup
2024-11-15 19:13:57 +00:00
Eric Huss
03e2828e88 Fix span edition for 2024 RPIT coming from an external macro
This fixes a problem where code generated by an external macro with an
RPIT would end up using the call-site edition instead of the macro's
edition for the RPIT. When used from a 2024 crate, this caused the code
to change behavior to the 2024 capturing rules, which we don't want.

This was caused by the impl-trait lowering code would replace the span
with one marked with `DesugaringKind::OpaqueTy` desugaring. However, it
was also overriding the edition of the span with the edition of the
local crate. Instead it should be using the edition of the span itself.

Fixes https://github.com/rust-lang/rust/issues/132917
2024-11-15 10:06:53 -08:00
Matthias Krüger
249a9100a3
Rollup merge of #133045 - mrkajetanp:pauth-test-clang-lto-flag-merge, r=jieyouxu
tests: Test pac-ret flag merging on clang with LTO

Extend the test for pac-ret with clang and LTO by checking that different branch protection flags are preserved after the LTO step. There was an issue in older LLVM versions that was causing this to behave incorrectly.

try-job: aarch64-gnu-debug
2024-11-15 19:05:18 +01:00
Matthias Krüger
213803549a
Rollup merge of #132817 - compiler-errors:impl-trait-overcaptures-apit, r=BoxyUwU
Recurse into APITs in `impl_trait_overcaptures`

We were previously not detecting cases where an RPIT was located in the return type of an async function, leading to underfiring of the `impl_trait_overcaptures`. This PR does this recursion properly now.

cc https://github.com/rust-lang/rust/issues/132809
2024-11-15 19:05:15 +01:00
Eric Huss
d163541022 Add test for precise-capturing from an external macro 2024-11-15 09:54:06 -08:00
Tyrone Wu
dd557c988f
Trim whitespace in RemoveLet primary span
Separate `RemoveLet` span into primary span for `let` and removal
suggestion span for `let `, so that primary span does not include
whitespace.

Fixes: #133031

Signed-off-by: Tyrone Wu <wudevelops@gmail.com>
2024-11-15 17:43:29 +00:00
bors
ce40196577 Auto merge of #132992 - RalfJung:check-consts-feature-gate, r=compiler-errors
check_consts: fix error requesting feature gate when that gate is not actually needed

When working on https://github.com/rust-lang/hashbrown/pull/586 I noticed that the compiler asks for the `rustc_private` feature to be enabled if one forgets to set `rustc_const_stable_indirect` on a function -- but enabling `rustc_private` would not actually help. This fixes the diagnostics.

r? `@compiler-errors`
2024-11-15 16:03:47 +00:00
Jorge Aparicio
7f0275636e make UI test OS-agnostic
the internal representation of `std::sync::Mutex` depends on the compilation target. due to this,
the compiler produces different number of errors for UI test
`issue-17431-6.rs` depending on the compilation target.

for example, when compiling the UI test to an `*-apple-*` or `*-qnx7*` target, the "cycle detected"
error is not reported

``` console
$ cat src/lib.rs
use std::sync::Mutex;

enum Foo {
    X(Mutex<Option<Foo>>),
}

impl Foo {
    fn bar(self) {}
}

fn main() {}

$ cargo check --target x86_64-apple-ios 2>&1 | rg '^error\['
error[E0072]: recursive type `Foo` has infinite size
```

whereas rustc produces two errors for other OSes, like Linux, which is what the UI test expects

``` console
$ cargo check --target x86_64-unknown-linux-gnu 2>&1 | rg '^error\['
error[E0072]: recursive type `Foo` has infinite size
error[E0391]: cycle detected when computing when `Foo` needs drop
```

this commit replaces the problematic `Mutex` with `UnsafeCell`, which has the same internal
representation regardless of the compilation target. with that change, rustc reports two errors for
all compilation targets.

``` console
$ cat src/lib.rs
use std::cell::UnsafeCell;

enum Foo {
    X(UnsafeCell<Option<Foo>>),
}

impl Foo {
    fn bar(self) {}
}

fn main() {}

$ cargo check --target x86_64-apple-ios 2>&1 | rg '^error\['
error[E0072]: recursive type `Foo` has infinite size
error[E0391]: cycle detected when computing when `Foo` needs drop
```

with this change, we can remove the `ignore-apple` directive as the UI test now also passes on apple
targets.
2024-11-15 16:37:18 +01:00
Kajetan Puchalski
194471cbd4 tests: Test pac-ret flag merging on clang with LTO
Extend the test for pac-ret with clang and LTO by checking that
different branch protection flags are preserved after the LTO step.
There was an issue in older LLVM versions that was causing this to
behave incorrectly.

Tests the LLVM behaviour added in:
1782810b84
2024-11-15 14:13:38 +00:00
Jubilee
efe2c44269
Rollup merge of #133053 - liushuyu:simd-test-x86-baseline-fix, r=workingjubilee
tests: Fix the SIMD FFI tests with certain x86 configuration

This pull request fixes the SIMD FFI tests with certain x86 configurations by gating the SSE2 intrinsic behind the `sse2` feature gate. A generic LLVM intrinsic that is easy to un-fuse on those platforms is added to compensate for those platforms.
2024-11-14 17:55:27 -08:00
Jubilee
cea081e980
Rollup merge of #133050 - tgross35:inline-f16-f128, r=saethlin
Always inline functions signatures containing `f16` or `f128`

There are a handful of tier 2 and tier 3 targets that cause a LLVM crash or linker error when generating code that contains `f16` or `f128`. The cranelift backend also does not support these types. To work around this, every function in `std` or `core` that contains these types must be marked `#[inline]` in order to avoid sending any code to the backend unless specifically requested.

However, this is inconvenient and easy to forget. Introduce a check for these types in the frontend that automatically inlines any function signatures that take or return `f16` or `f128`.

Note that this is not a perfect fix because it does not account for the types being passed by reference or as members of aggregate types, but this is sufficient for what is currently needed in the standard library.

Fixes: https://github.com/rust-lang/rust/issues/133035
Closes: https://github.com/rust-lang/rust/pull/133037
2024-11-14 17:55:27 -08:00
Jubilee
fcc084520c
Rollup merge of #132905 - xingxue-ibm:link-unwind, r=bjorn3
[AIX] Add crate "unwind" to link with libunwind

The Rust on IBM AIX uses LLVM's `libunwind`. Since crate `unwind` is a dependency of crate `std` and `#![no_std]` is specified in the test case, `libunwind` is not included in the link command by default. As a result, the test case fails to link with the error "Undefined symbol: ._Unwind_Resume" on AIX. This PR explicitly adds crate `unwind` for AIX, along with feature `panic_unwind`, which is required to include the `unwind` crate.
2024-11-14 17:55:24 -08:00
liushuyu
0733ed77d1
tests/run-make/simd-ffi: use a generic LLVM intrinsics ...
... to do more comprehensive type checking
2024-11-14 15:49:51 -07:00
Trevor Gross
5d818914af Always inline functions signatures containing f16 or f128
There are a handful of tier 2 and tier 3 targets that cause a LLVM crash
or linker error when generating code that contains `f16` or `f128`. The
cranelift backend also does not support these types. To work around
this, every function in `std` or `core` that contains these types must
be marked `#[inline]` in order to avoid sending any code to the backend
unless specifically requested.

However, this is inconvenient and easy to forget. Introduce a check for
these types in the frontend that automatically inlines any function
signatures that take or return `f16` or `f128`.

Note that this is not a perfect fix because it does not account for the
types being passed by reference or as members of aggregate types, but
this is sufficient for what is currently needed in the standard library.

Fixes: https://github.com/rust-lang/rust/issues/133035
Closes: https://github.com/rust-lang/rust/pull/133037
2024-11-14 16:18:41 -06:00
bors
e84902d35a Auto merge of #133047 - matthiaskrgr:rollup-9se1vth, r=matthiaskrgr
Rollup of 4 pull requests

Successful merges:

 - #128197 (Skip locking span interner for some syntax context checks)
 - #133040 ([rustdoc] Fix handling of footnote reference in footnote definition)
 - #133043 (rustdoc-search: case-sensitive only when capitals are used)
 - #133046 (Clippy subtree update)

r? `@ghost`
`@rustbot` modify labels: rollup
2024-11-14 21:09:28 +00:00
liushuyu
ede8a74f1e tests/run-make/simd-ffi: fix test crashing on x86 targets ...
... that do not have SSE2 support (e.g. i586)
2024-11-14 14:07:47 -07:00
Matthias Krüger
8912909b98
Rollup merge of #133043 - notriddle:master, r=fmease
rustdoc-search: case-sensitive only when capitals are used

This is the "smartcase" behavior, described by vim and dtolnay.

Fixes https://github.com/rust-lang/rust/issues/133017
2024-11-14 20:45:15 +01:00
Michael Howell
32500aa8e0 rustdoc-search: case-sensitive only when capitals are used
This is the "smartcase" behavior, described by vim and dtolnay.
2024-11-14 11:10:14 -07:00
Guillaume Gomez
052d40adb3 Add regression test for #131946 2024-11-14 17:01:29 +01:00
Xing Xue
467ce2695a Include the "unwind" crate to link with libunwind instead of the "libc" crate. 2024-11-14 10:51:28 -05:00
Guillaume Gomez
fc7ca70013
Rollup merge of #133005 - notriddle:notriddle/trie-search, r=GuillaumeGomez
rustdoc: use a trie for name-based search

Potentially https://github.com/rust-lang/rust/issues/131156 — need to try reproducing the problem with `windows`

Preview and profiler results
----------------------------

Here's some quick profiling in Firefox done on the rust compiler docs:

- Before: https://share.firefox.dev/3UPm3M8
- After: https://share.firefox.dev/40LXvYb

Here's the results for the node.js profiler:

- https://notriddle.com/rustdoc-html-demo-15/trie-perf/index.html

Here's a copy that you can use to try it out. Compare it with [the nightly]. Try typing `typecheckercontext` one character at a time, slowly.

- https://notriddle.com/rustdoc-html-demo-15/compiler-doc-trie/index.html

[the nightly]: https://doc.rust-lang.org/nightly/nightly-rustc/

The fuzzy match algo is based on [Fast String Correction with Levenshtein-Automata] and the corresponding implementation code in [moman] and [Lucene]; the bit-packing representation comes from Lucene, but the actual matcher is more based on `fsc.py`. As suggested in the paper, a trie is used to represent the FSA dictionary.

The same trie is used for prefix matching. Substring matching is done with a side table of three-character[^1] windows that point into the trie.

[Fast String Correction with Levenshtein-Automata]: https://github.com/tpn/pdfs/blob/master/Fast%20String%20Correction%20with%20Levenshtein-Automata%20(2002)%20(10.1.1.16.652).pdf
[Lucene]: https://fossies.org/linux/lucene/lucene/core/src/java/org/apache/lucene/util/automaton/Lev1TParametricDescription.java
[moman]: https://gitlab.com/notriddle/moman-rustdoc

User-visible changes
--------------------

I don't expect anybody to notice anything, but it does cause two changes:

- Substring matches, in the middle of a name, only apply if there's three or more characters in the search query.
- Levenshtein distance limit now maxes out at two. In the old version, the limit was w/3, so you could get looser matches for queries with 9 or more characters[^1] in them.
- It uses more RAM.
- It's faster (assuming you don't swap thrash).

[^1]: technically utf-16 code units
2024-11-14 15:16:14 +01:00
Guillaume Gomez
5ee347ece4
Rollup merge of #132172 - dianne:suggest-borrow-generic, r=matthewjasper
borrowck diagnostics: suggest borrowing function inputs in generic positions

# Summary
This generalizes borrowck's existing suggestions to borrow instead of moving when passing by-value to a function that's generic in that input. Previously, this was special-cased to `AsRef`/`Borrow`-like traits and `Fn`-like traits. This PR changes it to test if, for a moved place with type `T`, that the callee's signature and clauses don't break if you substitute in `&T` or `&mut T`. For instance, it now works with `Read`/`Write`-like traits.

Fixes https://github.com/rust-lang/rust/issues/131413

# Incidental changes
- No longer spuriously suggests mutable borrows of closures in some situations (see e.g. the tests in [tests/ui/closures/2229_closure_analysis/](https://github.com/rust-lang/rust/compare/master...dianne:rust:suggest-borrow-generic?expand=1#diff-8dfb200c559f0995d0f2ffa2f23bc6f8041b263e264e5c329a1f4171769787c0)).
- No longer suggests cloning closures that implement `Fn`, since they can be borrowed (see e.g. [tests/ui/moves/borrow-closures-instead-of-move.stderr](https://github.com/rust-lang/rust/compare/master...dianne:rust:suggest-borrow-generic?expand=1#diff-5db268aac405eec56d099a72d8b58ac46dab523cf013e29008104840168577fb)).

This keeps the behavior to suppress suggestions of `fn_once.clone()()`. I think it might make sense to suggest it with a "but this might not be your desired behavior" caveat, as is done when something is used after being consumed as the receiver for a method call. That's probably out of the scope of this PR though.

# Limitations and possible improvements
- This doesn't work for receivers of method calls. This is a small change, and I have it implemented locally, but I'm not sure it's useful on its own. In most cases I've found borrowing the receiver would change the call's output type (see below). In other cases (e.g. `Iterator::sum`), borrowing the receiver isn't useful since it's consumed.
- This doesn't work when it would change the call's output type. In general, I figure inserting references into the output type is an unwanted change. However, this also means it doesn't work in cases where the new output type would be effectively the same as the old one. For example, from the rand crate, the iterator returned by [`Rng::sample_iter`](https://docs.rs/rand/latest/rand/trait.Rng.html#method.sample_iter) is effectively the same (modulo regions) whether you borrow or consume the receiver `Rng`, so common usage involves borrowing it. I'm not sure whether the best approach is to add a more complex check of approximate equivalence, to forego checking the call's output type and give spurious suggestions, or to leave it as-is.
- This doesn't work when it would change the call's other input types. Instead, it could suggest borrowing any others that have the same parameter type (but only when suggesting shared borrows). I think this would be a pretty easy change, but I don't think it's very useful so long as the normalized output type can't change.

I'm happy to implement any of these (or other potential improvements to this), but I'm not sure which are common enough patterns to justify the added complexity. Please let me know if any sound worthwhile.
2024-11-14 15:16:08 +01:00