Commit Graph

200339 Commits

Author SHA1 Message Date
Ding Xiang Fei
eb36f5ee5b
add miri test via const fn 2022-09-18 12:18:34 +08:00
Ding Xiang Fei
d510ba3bc3
add mir-opt test 2022-09-18 12:10:56 +08:00
Ding Xiang Fei
48c1c1d190
avoid duplicating StorageLive in let-else 2022-09-18 12:10:53 +08:00
bors
65c16dc3a8 Auto merge of #101960 - matthiaskrgr:rollup-1l5v7ip, r=matthiaskrgr
Rollup of 5 pull requests

Successful merges:

 - #101151 (Document x86_64-fortanix-unknown-sgx platform)
 - #101912 (Update `unicode-rs` crates to Unicode 15)
 - #101923 (Don't add rustdoc's CSS to other doc pages)
 - #101953 (Fix tooltip display for error codes)
 - #101954 (rustdoc: remove redundant `.location a { font-weight: 500 }`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-09-18 03:40:01 +00:00
Scott McMurray
335690200e Add a codegen test for slice::from_ptr_range 2022-09-17 18:54:00 -07:00
Matthias Krüger
c0e8d46e20
Rollup merge of #101954 - notriddle:notriddle/location-a-first-of-type, r=GuillaumeGomez
rustdoc: remove redundant `.location a { font-weight: 500 }`

The `class="location"` element is an h2, either in the sidebar or in the mobile header. Either way, it already has `font-weight: 500`, which the link inside will inherit.

The original version of this rule was added in 9e82fc7ef9. At that time, the location header was rendered as a paragraph with the full path:

9e82fc7ef9/src/librustdoc/html/render.rs (L2080)

Nowadays, it's rendered as a true header, with only the name of the item, and the full path is included in a separate `fqn` header:

98ad6a5519/src/librustdoc/html/render/mod.rs (L1797)
2022-09-18 02:55:31 +02:00
Matthias Krüger
fb20485592
Rollup merge of #101953 - GuillaumeGomez:fix-error-code-tooltip, r=notriddle
Fix tooltip display for error codes

Fixes #101919.

You can test it [here](https://rustdoc.crud.net/imperio/fix-error-code-tooltip/index.html).

cc `@jsha`
r? `@notriddle`
2022-09-18 02:55:30 +02:00
Matthias Krüger
4c0b52013d
Rollup merge of #101923 - jsha:aux-pages-no-rustdoc-css, r=Mark-Simulacrum
Don't add rustdoc's CSS to other doc pages

This was originally added so those doc pages could use the same font files, but it turns out to be fragile. And those doc pages are just stubs that link to other pages, so they don't need fancy fonts.

Before:

![Screenshot from 2022-09-16 16-45-44](https://user-images.githubusercontent.com/220205/190831650-b626ee66-046a-4b71-8e57-dd06872359db.png)

After:

![Screenshot from 2022-09-16 16-52-06](https://user-images.githubusercontent.com/220205/190831657-f7d10a3f-d8c0-48a3-b30d-666db5a50563.png)

Demo of all affected pages:

https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/complement-design-faq.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/complement-lang-faq.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/complement-project-faq.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/grammar.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-crates.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-error-handling.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-ffi.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-macros.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-ownership.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-plugins.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-pointers.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-strings.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-tasks.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-testing.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/guide-unsafe.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/index.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/intro.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/not_found.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/reference.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/rustdoc.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/rust.html
https://rustdoc.crud.net/jsha/aux-pages-no-rustdoc-css/tutorial.html

Prior art: https://github.com/rust-lang/rust/pull/86663
2022-09-18 02:55:30 +02:00
Matthias Krüger
46ebe7cf41
Rollup merge of #101912 - crlf0710:compiler_update_unicode_15, r=Manishearth
Update `unicode-rs` crates to Unicode 15

r? `@Manishearth`
2022-09-18 02:55:29 +02:00
Matthias Krüger
f62b8261d8
Rollup merge of #101151 - jethrogb:jb/sgx-platform, r=JohnTitor
Document x86_64-fortanix-unknown-sgx platform

cc `@raoulstrackx` `@mzohreva`
2022-09-18 02:55:29 +02:00
bors
bc7b17cfe3 Auto merge of #101862 - cjgillot:lint-regression, r=oli-obk
Do not fetch HIR node when iterating to find lint.

Addresses the regression in https://github.com/rust-lang/rust/pull/101620
2022-09-18 00:46:14 +00:00
hanar3
0405a5d4e9 improve error message for when a query isn't supported 2022-09-17 20:25:37 -03:00
jam1garner
527f7887b8
Fix typo in proc_macro Span::eq 2022-09-17 19:15:30 -04:00
Michael Howell
b693d2cadf rustdoc: remove redundant .location a { font-weight: 500 }
The `class="location"` element is an h2, either in the sidebar or in the
mobile header. Either way, it already has `font-weight: 500`, which the link
inside will inherit.

The original version of this rule was added in
9e82fc7ef9. At that time, the location header
was rendered as a paragraph with the full path:

9e82fc7ef9/src/librustdoc/html/render.rs (L2080)

Nowadays, it's rendered as a true header, with only the name of the item,
and the full path is included in a separate `fqn` header:

98ad6a5519/src/librustdoc/html/render/mod.rs (L1797)
2022-09-17 15:33:12 -07:00
Guillaume Gomez
f45eacce76 Fix tooltip display for error codes 2022-09-18 00:32:28 +02:00
bors
5253b0a0a1 Auto merge of #101949 - matthiaskrgr:rollup-xu5cqnd, r=matthiaskrgr
Rollup of 7 pull requests

Successful merges:

 - #101093 (Initial version of 1.64 release notes)
 - #101713 (change AccessLevels representation)
 - #101821 (Bump Unicode to version 15.0.0, regenerate tables)
 - #101826 (Enforce "joined()" and "joined_with_noop()" test)
 - #101835 (Allow using vendoring when running bootstrap from outside the source root)
 - #101942 (Revert "Copy stage0 binaries into stage0-sysroot")
 - #101943 (rustdoc: remove unused CSS `.non-exhaustive { margin-bottom }`)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-09-17 22:04:28 +00:00
Matthias Krüger
5ba52ca002
Rollup merge of #101943 - notriddle:notriddle/non-exhaustive, r=GuillaumeGomez
rustdoc: remove unused CSS `.non-exhaustive { margin-bottom }`

This selector was added in 959a13d53e to target a `<div class="non-exhaustive">`. With 4edcf61479, the non-exhaustive indicator was changed to a `<details>`, and a separate selector targetting `details.non-exhaustive` was added for it, but the old selector was never removed.
2022-09-17 23:30:51 +02:00
Matthias Krüger
626c36a88d
Rollup merge of #101942 - Mark-Simulacrum:fix-perf, r=jyn514
Revert "Copy stage0 binaries into stage0-sysroot"

This reverts PR #101711.

The PR broke the rustc/bootstrap benchmark on rustc-perf, I believe due to the assumption that the stage0 directory exists. Fixing that by just skipping this logic might be reasonable, but I think there's a larger discussion to be had around the right behavior when we don't have a single bin/ directory (when rustc= and cargo= are specified in config.toml). I think it's potentially reasonable to put those binaries (cargo, rustc, rustfmt?) into the bin directory, but for now just want to get us back to a healthy state.

r? `@jyn514` (but would appreciate review from others as this is just a direct revert).
2022-09-17 23:30:50 +02:00
Matthias Krüger
cda20a7da6
Rollup merge of #101835 - jyn514:fix-vendoring, r=Mark-Simulacrum
Allow using vendoring when running bootstrap from outside the source root

Fixes https://github.com/rust-lang/rust/issues/100364.
2022-09-17 23:30:50 +02:00
Matthias Krüger
bfbb15a479
Rollup merge of #101826 - andrewpollack:fix-joined-without-noop, r=Mark-Simulacrum
Enforce "joined()" and "joined_with_noop()" test

Several similar tests come in the form of `joined()` and `joined_with_noop()`. In this test, the `joined()` has two calls to a noop, making it functionally equivalent to `joined_with_noop()`. This doesn't seem intended, and this PR removes those calls and changes the memory size to reflect the change

For my education, why do tests with `noop()` calls sometimes have `noop()` contributing to the size, while others do not? E.g. https://github.com/rust-lang/rust/blob/master/src/test/ui/async-await/async-fn-size-moved-locals.rs#L115 and https://github.com/rust-lang/rust/blob/master/src/test/ui/async-await/async-fn-size-moved-locals.rs#L116 have no size difference, whereas https://github.com/rust-lang/rust/blob/master/src/test/ui/async-await/async-fn-size-moved-locals.rs#L113 and https://github.com/rust-lang/rust/blob/master/src/test/ui/async-await/async-fn-size-moved-locals.rs#L114 have a size difference. Thank you!
2022-09-17 23:30:50 +02:00
Matthias Krüger
36b066daa4
Rollup merge of #101821 - thomcc:unicode-15, r=Manishearth
Bump Unicode to version 15.0.0, regenerate tables

r? `@Mark-Simulacrum`
2022-09-17 23:30:49 +02:00
Matthias Krüger
a6b34cd928
Rollup merge of #101713 - Bryanskiy:AccessLevels, r=petrochenkov
change AccessLevels representation

Part of RFC (https://github.com/rust-lang/rust/issues/48054). This patch implements effective visibility table with basic methods and change AccessLevels table representation according to it.

r? ``@petrochenkov``
2022-09-17 23:30:49 +02:00
Matthias Krüger
83623215ad
Rollup merge of #101093 - joshtriplett:relnotes-1.64, r=Mark-Simulacrum
Initial version of 1.64 release notes

Needs further expansion on some points, with text that will likely end up in
the blog post as well.

Also adds the release notes from 1.62.1 and 1.63, which weren't present on the
branch.
2022-09-17 23:30:48 +02:00
Luca Palmieri
235dccef2b Add a new component, rust-json-docs, to distribute the JSON-formatted documentation for std crates in nightly toolchains.
We also add a new flag to `x doc`, `--json`, to render the JSON-formatted version alongside the HTML-formatted one.
2022-09-17 21:58:34 +02:00
bors
98ad6a5519 Auto merge of #101946 - matthiaskrgr:rollup-jqkhsku, r=matthiaskrgr
Rollup of 9 pull requests

Successful merges:

 - #101672 (array docs - advertise how to get array from slice)
 - #101781 (Extend list of targets that support dyanmic linking for llvm tools)
 - #101783 (Improve handing of env vars during bootstrap process)
 - #101801 (add note for `layout_of` when query depth overflows)
 - #101824 (rustdoc: add test cases for turning ``[Vec<T>]`` into ``[`Vec<T>`]``)
 - #101861 (Update stdarch)
 - #101873 (Allow building `rust-analyzer-proc-macro-srv` as a standalone tool)
 - #101918 (rustdoc: clean up CSS for All Items and All Crates lists)
 - #101934 (Continue migration of CSS themes)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-09-17 19:33:52 +00:00
Mark Rousskov
a924b8a8fb Release notes update
Co-authored-by: Tyler Mandry <tmandry@gmail.com>
Co-authored-by: Josh Triplett <josh@joshtriplett.org>
2022-09-17 13:48:06 -04:00
Matthias Krüger
1f31bee266
Rollup merge of #101934 - GuillaumeGomez:theme-links-cleanup, r=notriddle
Continue migration of CSS themes

Now that https://github.com/rust-lang/rust/pull/101898 has been merged, we can move forward.

This PR moves more CSS theme rules as CSS variables. I also added a GUI test to prevent regressions.

Part of https://github.com/rust-lang/rust/pull/98460.

r? ``@notriddle``
2022-09-17 19:27:09 +02:00
Matthias Krüger
9702c6cacf
Rollup merge of #101918 - notriddle:notriddle/all, r=GuillaumeGomez
rustdoc: clean up CSS for All Items and All Crates lists

This reduces the amount of CSS, and makes these two pages more consistent (which, necessarily, means changing them a bit).

# Before

![image](https://user-images.githubusercontent.com/1593513/190735035-c66b2664-3783-483c-9bc6-89f80e4a5490.png)

![image](https://user-images.githubusercontent.com/1593513/190735134-1d5df81d-58c5-4c86-b066-6dd3031ffc2e.png)

# After

![image](https://user-images.githubusercontent.com/1593513/190735261-fc3878bb-0cab-4c4e-a6da-b5f7abd06588.png)

![image](https://user-images.githubusercontent.com/1593513/190735389-935a7836-f2c0-4349-a7d0-7fe5378f6b9a.png)
2022-09-17 19:27:08 +02:00
Matthias Krüger
179fd13e80
Rollup merge of #101873 - WaffleLapkin:x-build-proc-macro-srv, r=jyn514
Allow building `rust-analyzer-proc-macro-srv` as a standalone tool

This PR allows building `rust-analyzer-proc-macro-srv` as a standalone tool via `x b proc-macro-srv-cli` (I thought that `x b rust-analyzer-proc-macro-srv` should work, but it doesn't for some reason...). Also this PR adds a copy of `rust-analyzer-proc-macro-srv` binary to `build/{triple}/{stage}/libexec/` when building `rust-analyzer-proc-macro-srv`, so that r-a can pick it up.

This is useful to make r-a (and I assume Intellij IDEA) to expand macros when using a custom, build from source toolchain.

r? ``@jyn514``
[_zulip thread_](https://rust-lang.zulipchat.com/#narrow/stream/185405-t-compiler.2Frust-analyzer/topic/How.20to.20fix.20.60UnsupportedABI.60.20for.20custom.20toolchains.3F/near/299040175)
2022-09-17 19:27:08 +02:00
Matthias Krüger
92d8bf918c
Rollup merge of #101861 - wesleywiser:update_stdarch, r=Amanieu
Update stdarch

This pulls in the following changes:

- [Use simd_bitmask intrinsic in a couple of places](9f0928782b)
- [Remove simd_shuffle<n> usage in favor of simd_shuffle](3fd17e4607)
- [Remove late specifiers in __cpuid_count](f1db941633)
  - Helps with #101346
- [Use mov and xchg instead of movl(q) and xchgl(q)](3049a31937)
- [Bump cfg-if dependency to 1.0](f305cc83e7)
- [Fix documentation of __m256bh and __m512bh structs](699c093a42)

r? ``@Amanieu``
2022-09-17 19:27:07 +02:00
Matthias Krüger
030f453d0e
Rollup merge of #101824 - notriddle:notriddle/html-as-generics-intra-doc-links, r=Mark-Simulacrum
rustdoc: add test cases for turning ``[Vec<T>]`` into ``[`Vec<T>`]``
2022-09-17 19:27:07 +02:00
Matthias Krüger
4757d2d57e
Rollup merge of #101801 - SparrowLii:query_depth_note, r=estebank
add note for `layout_of` when query depth overflows

Fixes #101747
Added `try_find_layout_root` function to add a note for `layout_of` when query depth overflows. This would make the error in #101747 look like this:
```
error: queries overflow the depth limit!
   |
note: Query depth increased by 66 when computing layout of `core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<core::option::Option<alloc::boxed::Box<alloc::string::String>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>`!
  --> D:\rust-backup\parallel_rust\query_depth.rs:40:1
   |
40 | fn main() {
   | ^^^^^^^^^

error: aborting due to previous error
```

cc ``@semicoleon``
2022-09-17 19:27:06 +02:00
Matthias Krüger
9c32773a8d
Rollup merge of #101783 - chriswailes:env-vars, r=jyn514
Improve handing of env vars during bootstrap process

This CL modifies the handing of env vars during the bootstrap process in two ways:
1. Replaces '-' characters with '_' characters in target names to increase compatibility with different shells
2. Passes Stage0 snapshot compiler related env vars to early invocations of Cargo
2022-09-17 19:27:06 +02:00
Matthias Krüger
ec6104784d
Rollup merge of #101781 - chriswailes:dynamic-llvm-on-musl, r=jyn514
Extend list of targets that support dyanmic linking for llvm tools

This commit adds `linux-musl` to the list of targets that support dynamic linking for the LLVM tools.
2022-09-17 19:27:05 +02:00
Matthias Krüger
00d88bdb2c
Rollup merge of #101672 - idigdoug:array_try_into, r=Mark-Simulacrum
array docs - advertise how to get array from slice

On my first Rust project, I spent more time than I care to admit figuring out how to efficiently get an array from a slice. Update the array documentation to explain this a bit more clearly.

(As a side note, it's a bit unfortunate that get-array-from-slice is only available via trait since that means it can't be used from const functions yet.)
2022-09-17 19:27:05 +02:00
bors
c773c134c9 Auto merge of #101890 - rust-lang:pa-bump-version, r=pietroalbini
Bump version to 1.66.0

Part of the release process.
2022-09-17 16:32:58 +00:00
Michael Howell
aeddd932a6 rustdoc: remove unused CSS .non-exhaustive { margin-bottom }
This selector was added in 959a13d53e to
target a `<div class="non-exhaustive">`. With
4edcf61479, the non-exhaustive indicator was
changed to a `<details>`, and a separate selector targetting
`details.non-exhaustive` was added for it, but the old selector was never
removed.
2022-09-17 09:00:51 -07:00
Jack Huey
e7ca6e1b47 Use Predicate ConstraintCategory when normalizing 2022-09-17 11:46:05 -04:00
Jack Huey
1eb71f0893 Add back in normalize call 2022-09-17 11:46:04 -04:00
Mark Rousskov
f0c78ee3dc Revert "fix #101691: copy stage0 binaries into stage0-sysroot"
This reverts commit 32f8eb2fee.
2022-09-17 11:03:40 -04:00
bors
48de123d7a Auto merge of #101857 - lcnr:make-dyn-again, r=jackh726
change `FnMutDelegate` to trait objects

cc #100016 as mentioned in the last t-compiler meeting

r? `@jackh726`
2022-09-17 13:37:48 +00:00
bors
932e63b5d4 Auto merge of #13239 - mdx97:mathew/fix-add-reference-for-macros, r=Veykril
Fix add reference action on macros.

Before we were using the range of the corresponding expression node in the macro expanded file, which is obviously incorrect as we are setting the text in the original source.

For some reason, the test I added is failing and I haven't found a way to fix it. Does anyone know why `check_fix` wouldn't work with macros? Getting this error:

```text
thread 'handlers::type_mismatch::tests::test_add_reference_to_macro_call' panicked at 'no diagnostics', crates/ide-diagnostics/src/handlers/type_mismatch.rs:317:9
```

closes #13219
2022-09-17 11:23:05 +00:00
bors
672831a5c8 Auto merge of #101938 - Dylan-DPC:rollup-6vlohhs, r=Dylan-DPC
Rollup of 6 pull requests

Successful merges:

 - #93628 (Stabilize `let else`)
 - #98441 (Implement simd_as for pointers)
 - #101790 (Do not suggest a placeholder to const and static without a type)
 - #101807 (Disallow defaults on type GATs)
 - #101915 (doc: fix redirected link in `/index.html`)
 - #101931 (doc: Fix a typo in `Rc::make_mut` docstring)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup
2022-09-17 10:56:42 +00:00
Dylan DPC
80cceb8f77
Rollup merge of #101931 - msakuta:master, r=thomcc
doc: Fix a typo in `Rc::make_mut` docstring

A very minor typo fix.
2022-09-17 15:31:09 +05:30
Dylan DPC
4515cb9621
Rollup merge of #101915 - notriddle:notriddle/redirect, r=GuillaumeGomez
doc: fix redirected link in `/index.html`

Fallout from #101166
2022-09-17 15:31:09 +05:30
Dylan DPC
7c55c992ab
Rollup merge of #101807 - jackh726:no-gat-defaults, r=lcnr
Disallow defaults on type GATs

Fixes #99205
2022-09-17 15:31:08 +05:30
Dylan DPC
4c64c14420
Rollup merge of #101790 - TaKO8Ki:do-not-suggest-placeholder-to-const-and-static-without-type, r=compiler-errors
Do not suggest a placeholder to const and static without a type

Fixes #101755
2022-09-17 15:31:08 +05:30
Dylan DPC
cbd561d41f
Rollup merge of #98441 - calebzulawski:simd_as, r=oli-obk
Implement simd_as for pointers

Expands `simd_as` (and `simd_cast`) to handle pointer-to-pointer, pointer-to-integer, and integer-to-pointer conversions.

cc ``@programmerjake`` ``@thomcc``
2022-09-17 15:31:07 +05:30
Dylan DPC
3ad81e0dd8
Rollup merge of #93628 - est31:stabilize_let_else, r=joshtriplett
Stabilize `let else`

🎉  **Stabilizes the `let else` feature, added by [RFC 3137](https://github.com/rust-lang/rfcs/pull/3137).** 🎉

Reference PR: https://github.com/rust-lang/reference/pull/1156

closes #87335 (`let else` tracking issue)

FCP: https://github.com/rust-lang/rust/pull/93628#issuecomment-1029383585

----------

## Stabilization report

### Summary

The feature allows refutable patterns in `let` statements if the expression is
followed by a diverging `else`:

```Rust
fn get_count_item(s: &str) -> (u64, &str) {
    let mut it = s.split(' ');
    let (Some(count_str), Some(item)) = (it.next(), it.next()) else {
        panic!("Can't segment count item pair: '{s}'");
    };
    let Ok(count) = u64::from_str(count_str) else {
        panic!("Can't parse integer: '{count_str}'");
    };
    (count, item)
}
assert_eq!(get_count_item("3 chairs"), (3, "chairs"));
```

### Differences from the RFC / Desugaring

Outside of desugaring I'm not aware of any differences between the implementation and the RFC. The chosen desugaring has been changed from the RFC's [original](https://rust-lang.github.io/rfcs/3137-let-else.html#reference-level-explanations). You can read a detailed discussion of the implementation history of it in `@cormacrelf` 's [summary](https://github.com/rust-lang/rust/pull/93628#issuecomment-1041143670) in this thread, as well as the [followup](https://github.com/rust-lang/rust/pull/93628#issuecomment-1046598419). Since that followup, further changes have happened to the desugaring, in #98574, #99518, #99954. The later changes were mostly about the drop order: On match, temporaries drop in the same order as they would for a `let` declaration. On mismatch, temporaries drop before the `else` block.

### Test cases

In chronological order as they were merged.

Added by df9a2e0687 (#87688):

* [`ui/pattern/usefulness/top-level-alternation.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/pattern/usefulness/top-level-alternation.rs) to ensure the unreachable pattern lint visits patterns inside `let else`.

Added by 5b95df4bdc (#87688):

* [`ui/let-else/let-else-bool-binop-init.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-bool-binop-init.rs) to ensure that no lazy boolean expressions (using `&&` or `||`) are allowed in the expression, as the RFC mandates.
* [`ui/let-else/let-else-brace-before-else.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-brace-before-else.rs) to ensure that no `}` directly preceding the `else` is allowed in the expression, as the RFC mandates.
* [`ui/let-else/let-else-check.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-check.rs) to ensure that `#[allow(...)]` attributes added to the entire `let` statement apply for the `else` block.
* [`ui/let-else/let-else-irrefutable.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-irrefutable.rs) to ensure that the `irrefutable_let_patterns` lint fires.
* [`ui/let-else/let-else-missing-semicolon.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-missing-semicolon.rs) to ensure the presence of semicolons at the end of the `let` statement.
* [`ui/let-else/let-else-non-diverging.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-non-diverging.rs) to ensure the `else` block diverges.
* [`ui/let-else/let-else-run-pass.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-run-pass.rs) to ensure the feature works in some simple test case settings.
* [`ui/let-else/let-else-scope.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-scope.rs) to ensure the bindings created by the outer `let` expression are not available in the `else` block of it.

Added by bf7c32a447 (#89965):

* [`ui/let-else/issue-89960.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/issue-89960.rs) as a regression test for the ICE-on-error bug #89960 . Later in 102b9125e1 this got removed in favour of more comprehensive tests.

Added by 856541963c (#89974):

* [`ui/let-else/let-else-if.rs`](https://github.com/rust-lang/rust/blob/1.58.1/src/test/ui/let-else/let-else-if.rs) to test for the improved error message that points out that `let else if` is not possible.

Added by 9b45713b6c:

* [`ui/let-else/let-else-allow-unused.rs`](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-allow-unused.rs) as a regression test for #89807, to ensure that `#[allow(...)]` attributes added to the entire `let` statement apply for bindings created by the `let else` pattern.

Added by 61bcd8d307 (#89841):

* [`ui/let-else/let-else-non-copy.rs`](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-non-copy.rs) to ensure that a copy is performed out of non-copy wrapper types. This mirrors `if let` behaviour. The test case bases on rustc internal changes originally meant for #89933 but then removed from the PR due to the error prior to the improvements of #89841.
* [`ui/let-else/let-else-source-expr-nomove-pass.rs `](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-source-expr-nomove-pass.rs) to ensure that while there is a move of the binding in the successful case, the `else` case can still access the non-matching value. This mirrors `if let` behaviour.

Added by 102b9125e1 (#89841):

* [`ui/let-else/let-else-ref-bindings.rs`](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-ref-bindings.rs) and [`ui/let-else/let-else-ref-bindings-pass.rs `](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-ref-bindings-pass.rs) to check `ref` and `ref mut` keywords in the pattern work correctly and error when needed.

Added by 2715c5f984 (#89841):

* Match ergonomic tests adapted from the `rfc2005` test suite.

Added by fec8a507a2 (#89841):

* [`ui/let-else/let-else-deref-coercion-annotated.rs`](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-deref-coercion-annotated.rs) and [`ui/let-else/let-else-deref-coercion.rs`](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-deref-coercion.rs) to check deref coercions.

#### Added since this stabilization report was originally written (2022-02-09)

Added by 76ea566677 (#94211):

* [`ui/let-else/let-else-destructuring.rs`](https://github.com/rust-lang/rust/blob/1.63.0/src/test/ui/let-else/let-else-destructuring.rs) to give a nice error message if an user tries to do an assignment with a (possibly refutable) pattern and an `else` block, like asked for in #93995.

Added by e7730dcb7e (#94208):

* [`ui/let-else/let-else-allow-in-expr.rs`](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-allow-in-expr.rs) to test whether `#[allow(unused_variables)]` works in the expr, as well as its non presence, as well as putting it on the entire `let else` *affects* the expr, too. This was adding a missing test as pointed out by the stabilization report.
* Expansion of `ui/let-else/let-else-allow-unused.rs` and `ui/let-else/let-else-check.rs` to ensure that non-presence of `#[allow(unused)]` does issue the unused lint. This was adding a missing test case as pointed out by the stabilization report.

Added by 5bd71063b3 (#94208):

* [`ui/let-else/let-else-slicing-error.rs`](https://github.com/rust-lang/rust/blob/1.61.0/src/test/ui/let-else/let-else-slicing-error.rs), a regression test for #92069, which got fixed without addition of a regression test. This resolves a missing test as pointed out by the stabilization report.

Added by 5374688e1d (#98574):

* [`src/test/ui/async-await/async-await-let-else.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/async-await/async-await-let-else.rs) to test the interaction of async/await with `let else`

Added by 6c529ded86 (#98574):

* [`src/test/ui/let-else/let-else-temporary-lifetime.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/let-else/let-else-temporary-lifetime.rs) as a (partial) regression test for #98672

Added by 9b56640106 (#99518):

* [`src/test/ui/let-else/let-else-temp-borrowck.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/let-else/let-else-temporary-lifetime.rs) as a regression test for #93951
* Extension of `src/test/ui/let-else/let-else-temporary-lifetime.rs` to include a partial regression test for #98672 (especially regarding `else` drop order)

Added by baf9a7cb57 (#99518):

* Extension of `src/test/ui/let-else/let-else-temporary-lifetime.rs` to include a partial regression test for #93951, similar to `let-else-temp-borrowck.rs`

Added by 60be2de8b7 (#99518):

* Extension of `src/test/ui/let-else/let-else-temporary-lifetime.rs` to include a program that can now be compiled thanks to borrow checker implications of #99518

Added by 47a7a91c96 (#100132):

* [`src/test/ui/let-else/issue-100103.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/let-else/issue-100103.rs), as a regression test for #100103, to ensure that there is no ICE when doing `Err(...)?` inside else blocks.

Added by e3c5bd617d (#100443):

* [`src/test/ui/let-else/let-else-then-diverge.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/let-else/let-else-then-diverge.rs), to verify that there is no unreachable code error with the current desugaring.

Added by 981852677c (#100443):

* [`src/test/ui/let-else/issue-94176.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/let-else/issue-94176.rs), to make sure that a correct span is emitted for a missing trailing expression error. Regression test for #94176.

Added by e182d12a84 (#100434):

* [src/test/ui/unpretty/pretty-let-else.rs](https://github.com/rust-lang/rust/blob/master/src/test/ui/unpretty/pretty-let-else.rs), as a regression test to ensure pretty printing works for `let else` (this bug surfaced in many different ways)

Added by e26285603c (#99954):

* [`src/test/ui/let-else/let-else-temporary-lifetime.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/let-else/let-else-temporary-lifetime.rs) extended to contain & borrows as well, as this was identified as an earlier issue with the desugaring: https://github.com/rust-lang/rust/issues/98672#issuecomment-1200196921

Added by 2d8460ef43 (#99291):

* [`src/test/ui/let-else/let-else-drop-order.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/let-else/let-else-drop-order.rs) a matrix based test for various drop order behaviour of `let else`. Especially, it verifies equality of `let` and `let else` drop orders, [resolving](https://github.com/rust-lang/rust/pull/93628#issuecomment-1238498468) a [stabilization blocker](https://github.com/rust-lang/rust/pull/93628#issuecomment-1055738523).

Added by 1b87ce0d40 (#101410):

* Edit to `src/test/ui/let-else/let-else-temporary-lifetime.rs` to add the `-Zvalidate-mir` flag, as a regression test for #99228

Added by af591ebe4d (#101410):

* [`src/test/ui/let-else/issue-99975.rs`](https://github.com/rust-lang/rust/blob/master/src/test/ui/let-else/issue-99975.rs) as a regression test for the ICE #99975.

Added by this PR:

* `ui/let-else/let-else.rs`, a simple run-pass check, similar to `ui/let-else/let-else-run-pass.rs`.

### Things not currently tested

* ~~The `#[allow(...)]` tests check whether allow works, but they don't check whether the non-presence of allow causes a lint to fire.~~ → *test added by e7730dcb7eb29a10ee73f269f4dc6e9d606db0da*
* ~~There is no `#[allow(...)]` test for the expression, as there are tests for the pattern and the else block.~~ → *test added by e7730dcb7eb29a10ee73f269f4dc6e9d606db0da*
* ~~`let-else-brace-before-else.rs` forbids the `let ... = {} else {}` pattern and there is a rustfix to obtain `let ... = ({}) else {}`. I'm not sure whether the `.fixed` files are checked by the tooling that they compile. But if there is no such check, it would be neat to make sure that `let ... = ({}) else {}` compiles.~~ → *test added by e7730dcb7eb29a10ee73f269f4dc6e9d606db0da*
* ~~#92069 got closed as fixed, but no regression test was added. Not sure it's worth to add one.~~ → *test added by 5bd71063b3810d977aa376d1e6dd7cec359330cc*
* ~~consistency between `let else` and `if let` regarding lifetimes and drop order: https://github.com/rust-lang/rust/pull/93628#issuecomment-1055738523~~ → *test added by 2d8460ef43d902f34ba2133fe38f66ee8d2fdafc*

Edit: they are all tested now.

### Possible future work / Refutable destructuring assignments

[RFC 2909](https://rust-lang.github.io/rfcs/2909-destructuring-assignment.html) specifies destructuring assignment, allowing statements like `FooBar { a, b, c } = foo();`.
As it was stabilized, destructuring assignment only allows *irrefutable* patterns, which before the advent of `let else` were the only patterns that `let` supported.
So the combination of `let else` and destructuring assignments gives reason to think about extensions of the destructuring assignments feature that allow refutable patterns, discussed in #93995.

A naive mapping of `let else` to destructuring assignments in the form of `Some(v) = foo() else { ... };` might not be the ideal way. `let else` needs a diverging `else` clause as it introduces new bindings, while assignments have a default behaviour to fall back to if the pattern does not match, in the form of not performing the assignment. Thus, there is no good case to require divergence, or even an `else` clause at all, beyond the need for having *some* introducer syntax so that it is clear to readers that the assignment is not a given (enums and structs look similar). There are better candidates for introducer syntax however than an empty `else {}` clause, like `maybe` which could be added as a keyword on an edition boundary:

```Rust
let mut v = 0;
maybe Some(v) = foo(&v);
maybe Some(v) = foo(&v) else { bar() };
```

Further design discussion is left to an RFC, or the linked issue.
2022-09-17 15:31:06 +05:30
bors
b195f5349a Auto merge of #101784 - reitermarkus:const-memchr, r=thomcc
Simplify `const` `memchr`.

Extracted from https://github.com/rust-lang/rust/pull/101607.

Removes the need for `const_eval_select`.
2022-09-17 08:15:35 +00:00