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Rollup merge of #141026 - tshepang:rust-push, r=jieyouxu 

rustc-dev-guide subtree update

r? ``@ghost``
This commit is contained in:
Matthias Krüger 2025-05-16 07:19:43 +02:00 committed by GitHub
parent 88c9c89490 70e08b3d42
commit 48e203443d
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GPG Key ID: B5690EEEBB952194
16 changed files with 200 additions and 171 deletions
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10
README.md
View File

@ -91,6 +91,16 @@ Older versions of `josh-proxy` may not round trip commits losslessly so it is im
3) Push the branch to your fork and create a PR into `rustc-dev-guide`
### Push changes from this repository into `rust-lang/rust`
NOTE: If you use Git protocol to push to your fork of `rust-lang/rust`,
ensure that you have this entry in your Git config,
else the 2 steps that follow would prompt for a username and password:
```
[url "git@github.com:"]
insteadOf = "https://github.com/"
```
1) Run the push command to create a branch named `<branch-name>` in a `rustc` fork under the `<gh-username>` account
```
cargo run --manifest-path josh-sync/Cargo.toml rustc-push <branch-name> <gh-username>

207
ci/date-check/Cargo.lock generated
View File

@ -1,6 +1,6 @@
# This file is automatically @generated by Cargo.
# It is not intended for manual editing.
version = 3
version = 4
[[package]]
name = "aho-corasick"
@ -28,21 +28,24 @@ dependencies = [
[[package]]
name = "autocfg"
version = "1.3.0"
version = "1.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "0c4b4d0bd25bd0b74681c0ad21497610ce1b7c91b1022cd21c80c6fbdd9476b0"
checksum = "ace50bade8e6234aa140d9a2f552bbee1db4d353f69b8217bc503490fc1a9f26"
[[package]]
name = "bumpalo"
version = "3.16.0"
version = "3.17.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "79296716171880943b8470b5f8d03aa55eb2e645a4874bdbb28adb49162e012c"
checksum = "1628fb46dfa0b37568d12e5edd512553eccf6a22a78e8bde00bb4aed84d5bdbf"
[[package]]
name = "cc"
version = "1.0.106"
version = "1.2.22"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "066fce287b1d4eafef758e89e09d724a24808a9196fe9756b8ca90e86d0719a2"
checksum = "32db95edf998450acc7881c932f94cd9b05c87b4b2599e8bab064753da4acfd1"
dependencies = [
"shlex",
]
[[package]]
name = "cfg-if"
@ -52,27 +55,27 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
[[package]]
name = "chrono"
version = "0.4.38"
version = "0.4.41"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "a21f936df1771bf62b77f047b726c4625ff2e8aa607c01ec06e5a05bd8463401"
checksum = "c469d952047f47f91b68d1cba3f10d63c11d73e4636f24f08daf0278abf01c4d"
dependencies = [
"android-tzdata",
"iana-time-zone",
"js-sys",
"num-traits",
"wasm-bindgen",
"windows-targets",
"windows-link",
]
[[package]]
name = "core-foundation-sys"
version = "0.8.6"
version = "0.8.7"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "06ea2b9bc92be3c2baa9334a323ebca2d6f074ff852cd1d7b11064035cd3868f"
checksum = "773648b94d0e5d620f64f280777445740e61fe701025087ec8b57f45c791888b"
[[package]]
name = "date-check"
version = "0.1.0"
version = "0.0.0"
dependencies = [
"chrono",
"glob",
@ -81,20 +84,21 @@ dependencies = [
[[package]]
name = "glob"
version = "0.3.1"
version = "0.3.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
checksum = "a8d1add55171497b4705a648c6b583acafb01d58050a51727785f0b2c8e0a2b2"
[[package]]
name = "iana-time-zone"
version = "0.1.60"
version = "0.1.63"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e7ffbb5a1b541ea2561f8c41c087286cc091e21e556a4f09a8f6cbf17b69b141"
checksum = "b0c919e5debc312ad217002b8048a17b7d83f80703865bbfcfebb0458b0b27d8"
dependencies = [
"android_system_properties",
"core-foundation-sys",
"iana-time-zone-haiku",
"js-sys",
"log",
"wasm-bindgen",
"windows-core",
]
@ -110,24 +114,25 @@ dependencies = [
[[package]]
name = "js-sys"
version = "0.3.69"
version = "0.3.77"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "29c15563dc2726973df627357ce0c9ddddbea194836909d655df6a75d2cf296d"
checksum = "1cfaf33c695fc6e08064efbc1f72ec937429614f25eef83af942d0e227c3a28f"
dependencies = [
"once_cell",
"wasm-bindgen",
]
[[package]]
name = "libc"
version = "0.2.155"
version = "0.2.172"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "97b3888a4aecf77e811145cadf6eef5901f4782c53886191b2f693f24761847c"
checksum = "d750af042f7ef4f724306de029d18836c26c1765a54a6a3f094cbd23a7267ffa"
[[package]]
name = "log"
version = "0.4.22"
version = "0.4.27"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
checksum = "13dc2df351e3202783a1fe0d44375f7295ffb4049267b0f3018346dc122a1d94"
[[package]]
name = "memchr"
@ -146,33 +151,33 @@ dependencies = [
[[package]]
name = "once_cell"
version = "1.19.0"
version = "1.21.3"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "3fdb12b2476b595f9358c5161aa467c2438859caa136dec86c26fdd2efe17b92"
checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"
[[package]]
name = "proc-macro2"
version = "1.0.86"
version = "1.0.95"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "5e719e8df665df0d1c8fbfd238015744736151d4445ec0836b8e628aae103b77"
checksum = "02b3e5e68a3a1a02aad3ec490a98007cbc13c37cbe84a3cd7b8e406d76e7f778"
dependencies = [
"unicode-ident",
]
[[package]]
name = "quote"
version = "1.0.36"
version = "1.0.40"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "0fa76aaf39101c457836aec0ce2316dbdc3ab723cdda1c6bd4e6ad4208acaca7"
checksum = "1885c039570dc00dcb4ff087a89e185fd56bae234ddc7f056a945bf36467248d"
dependencies = [
"proc-macro2",
]
[[package]]
name = "regex"
version = "1.10.5"
version = "1.11.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "b91213439dad192326a0d7c6ee3955910425f441d7038e0d6933b0aec5c4517f"
checksum = "b544ef1b4eac5dc2db33ea63606ae9ffcfac26c1416a2806ae0bf5f56b201191"
dependencies = [
"aho-corasick",
"memchr",
@ -182,9 +187,9 @@ dependencies = [
[[package]]
name = "regex-automata"
version = "0.4.7"
version = "0.4.9"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "38caf58cc5ef2fed281f89292ef23f6365465ed9a41b7a7754eb4e26496c92df"
checksum = "809e8dc61f6de73b46c85f4c96486310fe304c434cfa43669d7b40f711150908"
dependencies = [
"aho-corasick",
"memchr",
@ -193,15 +198,27 @@ dependencies = [
[[package]]
name = "regex-syntax"
version = "0.8.4"
version = "0.8.5"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "7a66a03ae7c801facd77a29370b4faec201768915ac14a721ba36f20bc9c209b"
checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
[[package]]
name = "rustversion"
version = "1.0.20"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "eded382c5f5f786b989652c49544c4877d9f015cc22e145a5ea8ea66c2921cd2"
[[package]]
name = "shlex"
version = "1.3.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
[[package]]
name = "syn"
version = "2.0.70"
version = "2.0.101"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "2f0209b68b3613b093e0ec905354eccaedcfe83b8cb37cbdeae64026c3064c16"
checksum = "8ce2b7fc941b3a24138a0a7cf8e858bfc6a992e7978a068a5c760deb0ed43caf"
dependencies = [
"proc-macro2",
"quote",
@ -210,29 +227,30 @@ dependencies = [
[[package]]
name = "unicode-ident"
version = "1.0.12"
version = "1.0.18"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
checksum = "5a5f39404a5da50712a4c1eecf25e90dd62b613502b7e925fd4e4d19b5c96512"
[[package]]
name = "wasm-bindgen"
version = "0.2.92"
version = "0.2.100"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "4be2531df63900aeb2bca0daaaddec08491ee64ceecbee5076636a3b026795a8"
checksum = "1edc8929d7499fc4e8f0be2262a241556cfc54a0bea223790e71446f2aab1ef5"
dependencies = [
"cfg-if",
"once_cell",
"rustversion",
"wasm-bindgen-macro",
]
[[package]]
name = "wasm-bindgen-backend"
version = "0.2.92"
version = "0.2.100"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "614d787b966d3989fa7bb98a654e369c762374fd3213d212cfc0251257e747da"
checksum = "2f0a0651a5c2bc21487bde11ee802ccaf4c51935d0d3d42a6101f98161700bc6"
dependencies = [
"bumpalo",
"log",
"once_cell",
"proc-macro2",
"quote",
"syn",
@ -241,9 +259,9 @@ dependencies = [
[[package]]
name = "wasm-bindgen-macro"
version = "0.2.92"
version = "0.2.100"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "a1f8823de937b71b9460c0c34e25f3da88250760bec0ebac694b49997550d726"
checksum = "7fe63fc6d09ed3792bd0897b314f53de8e16568c2b3f7982f468c0bf9bd0b407"
dependencies = [
"quote",
"wasm-bindgen-macro-support",
@ -251,9 +269,9 @@ dependencies = [
[[package]]
name = "wasm-bindgen-macro-support"
version = "0.2.92"
version = "0.2.100"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e94f17b526d0a461a191c78ea52bbce64071ed5c04c9ffe424dcb38f74171bb7"
checksum = "8ae87ea40c9f689fc23f209965b6fb8a99ad69aeeb0231408be24920604395de"
dependencies = [
"proc-macro2",
"quote",
@ -264,79 +282,68 @@ dependencies = [
[[package]]
name = "wasm-bindgen-shared"
version = "0.2.92"
version = "0.2.100"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "af190c94f2773fdb3729c55b007a722abb5384da03bc0986df4c289bf5567e96"
checksum = "1a05d73b933a847d6cccdda8f838a22ff101ad9bf93e33684f39c1f5f0eece3d"
dependencies = [
"unicode-ident",
]
[[package]]
name = "windows-core"
version = "0.52.0"
version = "0.61.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "33ab640c8d7e35bf8ba19b884ba838ceb4fba93a4e8c65a9059d08afcfc683d9"
checksum = "4763c1de310c86d75a878046489e2e5ba02c649d185f21c67d4cf8a56d098980"
dependencies = [
"windows-targets",
"windows-implement",
"windows-interface",
"windows-link",
"windows-result",
"windows-strings",
]
[[package]]
name = "windows-targets"
version = "0.52.6"
name = "windows-implement"
version = "0.60.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "9b724f72796e036ab90c1021d4780d4d3d648aca59e491e6b98e725b84e99973"
checksum = "a47fddd13af08290e67f4acabf4b459f647552718f683a7b415d290ac744a836"
dependencies = [
"windows_aarch64_gnullvm",
"windows_aarch64_msvc",
"windows_i686_gnu",
"windows_i686_gnullvm",
"windows_i686_msvc",
"windows_x86_64_gnu",
"windows_x86_64_gnullvm",
"windows_x86_64_msvc",
"proc-macro2",
"quote",
"syn",
]
[[package]]
name = "windows_aarch64_gnullvm"
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name = "windows-interface"
version = "0.59.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
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dependencies = [
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"quote",
"syn",
]
[[package]]
name = "windows_aarch64_msvc"
version = "0.52.6"
name = "windows-link"
version = "0.1.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "76840935b766e1b0a05c0066835fb9ec80071d4c09a16f6bd5f7e655e3c14c38"
[[package]]
name = "windows_i686_gnu"
version = "0.52.6"
name = "windows-result"
version = "0.3.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "8e9b5ad5ab802e97eb8e295ac6720e509ee4c243f69d781394014ebfe8bbfa0b"
checksum = "c64fd11a4fd95df68efcfee5f44a294fe71b8bc6a91993e2791938abcc712252"
dependencies = [
"windows-link",
]
[[package]]
name = "windows_i686_gnullvm"
version = "0.52.6"
name = "windows-strings"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "0eee52d38c090b3caa76c563b86c3a4bd71ef1a819287c19d586d7334ae8ed66"
[[package]]
name = "windows_i686_msvc"
version = "0.52.6"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "240948bc05c5e7c6dabba28bf89d89ffce3e303022809e73deaefe4f6ec56c66"
[[package]]
name = "windows_x86_64_gnu"
version = "0.52.6"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "147a5c80aabfbf0c7d901cb5895d1de30ef2907eb21fbbab29ca94c5b08b1a78"
[[package]]
name = "windows_x86_64_gnullvm"
version = "0.52.6"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "24d5b23dc417412679681396f2b49f3de8c1473deb516bd34410872eff51ed0d"
[[package]]
name = "windows_x86_64_msvc"
version = "0.52.6"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
checksum = "7a2ba9642430ee452d5a7aa78d72907ebe8cfda358e8cb7918a2050581322f97"
dependencies = [
"windows-link",
]

6
ci/date-check/Cargo.toml
View File

@ -1,10 +1,6 @@
[package]
name = "date-check"
version = "0.1.0"
authors = ["Noah Lev <camelidcamel@gmail.com>"]
edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
edition = "2024"
[dependencies]
glob = "0.3"

2
ci/date-check/src/main.rs
View File

@ -114,7 +114,7 @@ fn filter_dates(
fn main() {
let mut args = env::args();
if args.len() == 1 {
eprintln!("error: expected root Markdown directory as CLI argument");
eprintln!("error: expected root of Markdown directory as CLI argument");
process::exit(1);
}
let root_dir = args.nth(1).unwrap();

2
josh-sync/Cargo.lock generated
View File

@ -161,7 +161,7 @@ checksum = "7943c866cc5cd64cbc25b2e01621d07fa8eb2a1a23160ee81ce38704e97b8ecf"
[[package]]
name = "josh-sync"
version = "0.1.0"
version = "0.0.0"
dependencies = [
"anyhow",
"clap",

3
josh-sync/Cargo.toml
View File

@ -1,7 +1,6 @@
[package]
name = "josh-sync"
version = "0.1.0"
edition = "2021"
edition = "2024"
[dependencies]
anyhow = "1.0.95"

6
josh-sync/src/main.rs
View File

@ -1,4 +1,5 @@
use clap::Parser;
use crate::sync::{GitSync, RustcPullError};
mod sync;
@ -11,10 +12,7 @@ enum Args {
/// Push changes from `rustc-dev-guide` to the given `branch` of a `rustc` fork under the given
/// GitHub `username`.
/// The pushed branch should then be merged into the `rustc` repository.
RustcPush {
branch: String,
github_username: String
}
RustcPush { branch: String, github_username: String },
}
fn main() -> anyhow::Result<()> {

40
josh-sync/src/sync.rs
View File

@ -1,10 +1,11 @@
use std::io::Write;
use std::ops::Not;
use std::path::PathBuf;
use std::{env, net, process};
use std::io::Write;
use std::time::Duration;
use anyhow::{anyhow, bail, Context};
use xshell::{cmd, Shell};
use std::{env, net, process};
use anyhow::{Context, anyhow, bail};
use xshell::{Shell, cmd};
/// Used for rustc syncs.
const JOSH_FILTER: &str = ":/src/doc/rustc-dev-guide";
@ -15,10 +16,13 @@ pub enum RustcPullError {
/// No changes are available to be pulled.
NothingToPull,
/// A rustc-pull has failed, probably a git operation error has occurred.
PullFailed(anyhow::Error)
PullFailed(anyhow::Error),
}
impl<E> From<E> for RustcPullError where E: Into<anyhow::Error> {
impl<E> From<E> for RustcPullError
where
E: Into<anyhow::Error>,
{
fn from(error: E) -> Self {
Self::PullFailed(error.into())
}
@ -32,9 +36,7 @@ pub struct GitSync {
/// (https://github.com/rust-lang/miri/blob/6a68a79f38064c3bc30617cca4bdbfb2c336b140/miri-script/src/commands.rs#L236).
impl GitSync {
pub fn from_current_dir() -> anyhow::Result<Self> {
Ok(Self {
dir: std::env::current_dir()?
})
Ok(Self { dir: std::env::current_dir()? })
}
pub fn rustc_pull(&self, commit: Option<String>) -> Result<(), RustcPullError> {
@ -51,7 +53,10 @@ impl GitSync {
})?;
// Make sure the repo is clean.
if cmd!(sh, "git status --untracked-files=no --porcelain").read()?.is_empty().not() {
return Err(anyhow::anyhow!("working directory must be clean before performing rustc pull").into());
return Err(anyhow::anyhow!(
"working directory must be clean before performing rustc pull"
)
.into());
}
// Make sure josh is running.
let josh = Self::start_josh()?;
@ -94,7 +99,8 @@ impl GitSync {
};
let num_roots_before = num_roots()?;
let sha = cmd!(sh, "git rev-parse HEAD").output().context("FAILED to get current commit")?.stdout;
let sha =
cmd!(sh, "git rev-parse HEAD").output().context("FAILED to get current commit")?.stdout;
// Merge the fetched commit.
const MERGE_COMMIT_MESSAGE: &str = "Merge from rustc";
@ -102,18 +108,24 @@ impl GitSync {
.run()
.context("FAILED to merge new commits, something went wrong")?;
let current_sha = cmd!(sh, "git rev-parse HEAD").output().context("FAILED to get current commit")?.stdout;
let current_sha =
cmd!(sh, "git rev-parse HEAD").output().context("FAILED to get current commit")?.stdout;
if current_sha == sha {
cmd!(sh, "git reset --hard HEAD^")
.run()
.expect("FAILED to clean up after creating the preparation commit");
eprintln!("No merge was performed, no changes to pull were found. Rolled back the preparation commit.");
eprintln!(
"No merge was performed, no changes to pull were found. Rolled back the preparation commit."
);
return Err(RustcPullError::NothingToPull);
}
// Check that the number of roots did not increase.
if num_roots()? != num_roots_before {
return Err(anyhow::anyhow!("Josh created a new root commit. This is probably not the history you want.").into());
return Err(anyhow::anyhow!(
"Josh created a new root commit. This is probably not the history you want."
)
.into());
}
drop(josh);

2
rust-version
View File

@ -1 +1 @@
0c33fe2c3d3eecadd17a84b110bb067288a64f1c
414482f6a0d4e7290f614300581a0b55442552a3

6
src/macro-expansion.md
View File

@ -2,9 +2,6 @@
<!-- toc -->
> N.B. [`rustc_ast`], [`rustc_expand`], and [`rustc_builtin_macros`] are all
> undergoing refactoring, so some of the links in this chapter may be broken.
Rust has a very powerful macro system. In the previous chapter, we saw how
the parser sets aside macros to be expanded (using temporary [placeholders]).
This chapter is about the process of expanding those macros iteratively until
@ -12,9 +9,6 @@ we have a complete [*Abstract Syntax Tree* (AST)][ast] for our crate with no
unexpanded macros (or a compile error).
[ast]: ./ast-validation.md
[`rustc_ast`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_ast/index.html
[`rustc_expand`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_expand/index.html
[`rustc_builtin_macros`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_builtin_macros/index.html
[placeholders]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_expand/placeholders/index.html
First, we discuss the algorithm that expands and integrates macro output into

4
src/rustdoc-internals.md
View File

@ -55,8 +55,8 @@ The first step in [`clean::utils::krate`][ck1] is to invoke
* inlining public `use` exports of private items, or showing a "Reexport"
line in the module page
* inlining items with `#[doc(hidden)]` if the base item is hidden but the
* showing `#[macro_export]`-ed macros at the crate root, regardless of where
they're defined reexport is not
* showing `#[macro_export]`-ed macros at the crate root, regardless of whether
they're defined as a reexport or not
After this step, `clean::krate` invokes [`clean_doc_module`], which actually
converts the `HIR` items to the cleaned [`AST`][ast]. This is also the step where cross-

2
src/serialization.md
View File

@ -169,7 +169,7 @@ The `LazyArray<[T]>` and `LazyTable<I, T>` types provide some functionality over
than the one being read.
**note**: `LazyValue<T>` does not cache its value after being deserialized the
first time. Instead the query system its self is the main way of caching these
first time. Instead the query system itself is the main way of caching these
results.
[`LazyArray<T>`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_metadata/rmeta/struct.LazyValue.html

6
src/tests/best-practices.md
View File

@ -70,6 +70,11 @@ related tests.
> //!
> //! Regression test for <https://github.com/rust-lang/rust/issues/123456>.
> ```
>
> One exception to this rule is [crashes tests]: there it is canonical that
> tests are named only after issue numbers because its purpose is to track
> snippets from which issues no longer ICE/crash, and they would either be
> removed or converted into proper ui/other tests in the fix PRs.
## Test organization
@ -194,3 +199,4 @@ See [LLVM FileCheck guide][FileCheck] for details.
[compiletest directives]: ./directives.md
[`run-make`]: ./compiletest.md#run-make-tests
[FileCheck]: https://llvm.org/docs/CommandGuide/FileCheck.html
[crashes tests]: ./compiletest.md#crashes-tests

9
src/tests/intro.md
View File

@ -102,11 +102,12 @@ by passing a path to a book to `./x test`.
### Documentation link checker
Links across all documentation is validated with a link checker tool.
Links across all documentation is validated with a link checker tool,
and it can be invoked so:
> Example: `./x test src/tools/linkchecker`
> Example: `./x test linkchecker`
```console
./x test linkchecker
```
This requires building all of the documentation, which might take a while.

12
src/traits/unsize.md
View File

@ -32,21 +32,21 @@ Built-in implementations are provided for:
## Structural implementations
There are two implementations of `Unsize` which can be thought of as
There is one implementation of `Unsize` which can be thought of as
structural:
* `(A1, A2, .., An): Unsize<(A1, A2, .., U)>` given `An: Unsize<U>`, which
allows the tail field of a tuple to be unsized. This is gated behind the
[`unsized_tuple_coercion`] feature.
* `Struct<.., Pi, .., Pj, ..>: Unsize<Struct<.., Ui, .., Uj, ..>>` given
`TailField<Pi, .., Pj>: Unsize<Ui, .. Uj>`, which allows the tail field of a
struct to be unsized if it is the only field that mentions generic parameters
`Pi`, .., `Pj` (which don't need to be contiguous).
The rules for the latter implementation are slightly complicated, since they
The rules for struct unsizing are slightly complicated, since they
may allow more than one parameter to be changed (not necessarily unsized) and
are best stated in terms of the tail field of the struct.
[`unsized_tuple_coercion`]: https://doc.rust-lang.org/beta/unstable-book/language-features/unsized-tuple-coercion.html
(Tuple unsizing was previously implemented behind the feature gate
`unsized_tuple_coercion`, but the implementation was removed by [#137728].)
[#137728]: https://github.com/rust-lang/rust/pull/137728
## Upcasting implementations

54
src/ty-fold.md
View File

@ -1,26 +1,28 @@
<!-- date-check: may 2024 -->
# `TypeFoldable` and `TypeFolder`
In the previous chapter we discussed instantiating binders. This must involves looking at everything inside of a `Early/Binder`
to find any usages of the bound vars in order to replace them. Binders can wrap an arbitrary rust type `T` not just a `Ty` so
how do we implement the `instantiate` methods on the `Early/Binder` types.
In [a previous chapter], we discussed instantiating binders.
This involves looking at everything inside of a `Early(Binder)`
to find any usages of the bound vars in order to replace them.
Binders can wrap an arbitrary Rust type `T`, not just a `Ty`.
So, how do we implement the `instantiate` methods on the `Early/Binder` types?
The answer is a couple of traits:
[`TypeFoldable`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/fold/trait.TypeFoldable.html)
[`TypeFoldable`]
and
[`TypeFolder`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/fold/trait.TypeFolder.html).
[`TypeFolder`].
- `TypeFoldable` is implemented by types that embed type information. It allows you to recursively
process the contents of the `TypeFoldable` and do stuff to them.
- `TypeFolder` defines what you want to do with the types you encounter while processing the
`TypeFoldable`.
For example, the `TypeFolder` trait has a method
[`fold_ty`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/fold/trait.TypeFolder.html#method.fold_ty)
that takes a type as input and returns a new type as a result. `TypeFoldable` invokes the
`TypeFolder` `fold_foo` methods on itself, giving the `TypeFolder` access to its contents (the
types, regions, etc that are contained within).
For example, the `TypeFolder` trait has a method [`fold_ty`]
that takes a type as input and returns a new type as a result.
`TypeFoldable` invokes the `TypeFolder` `fold_foo` methods on itself,
giving the `TypeFolder` access to its contents (the types, regions, etc that are contained within).
You can think of it with this analogy to the iterator combinators we have come to love in rust:
You can think of it with this analogy to the iterator combinators we have come to love in Rust:
```rust,ignore
vec.iter().map(|e1| foo(e2)).collect()
@ -33,8 +35,7 @@ So to reiterate:
- `TypeFolder` is a trait that defines a “map” operation.
- `TypeFoldable` is a trait that is implemented by things that embed types.
In the case of `subst`, we can see that it is implemented as a `TypeFolder`:
[`ArgFolder`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_type_ir/binder/struct.ArgFolder.html).
In the case of `subst`, we can see that it is implemented as a `TypeFolder`: [`ArgFolder`].
Looking at its implementation, we see where the actual substitutions are happening.
However, you might also notice that the implementation calls this `super_fold_with` method. What is
@ -88,17 +89,22 @@ things. We only want to do something when we reach a type. That means there may
`TypeFoldable` types whose implementations basically just forward to their fields’ `TypeFoldable`
implementations. Such implementations of `TypeFoldable` tend to be pretty tedious to write by hand.
For this reason, there is a `derive` macro that allows you to `#![derive(TypeFoldable)]`. It is
defined
[here](https://github.com/rust-lang/rust/blob/master/compiler/rustc_macros/src/type_foldable.rs).
defined [here].
**`subst`** In the case of substitutions the [actual
folder](https://github.com/rust-lang/rust/blob/75ff3110ac6d8a0259023b83fd20d7ab295f8dd6/src/librustc_middle/ty/subst.rs#L440-L451)
is going to be doing the indexing we’ve already mentioned. There we define a `Folder` and call
`fold_with` on the `TypeFoldable` to process yourself. Then
[fold_ty](https://github.com/rust-lang/rust/blob/75ff3110ac6d8a0259023b83fd20d7ab295f8dd6/src/librustc_middle/ty/subst.rs#L512-L536)
the method that process each type it looks for a `ty::Param` and for those it replaces it for
something from the list of substitutions, otherwise recursively process the type. To replace it,
calls
[ty_for_param](https://github.com/rust-lang/rust/blob/75ff3110ac6d8a0259023b83fd20d7ab295f8dd6/src/librustc_middle/ty/subst.rs#L552-L587)
**`subst`** In the case of substitutions the [actual folder]
is going to be doing the indexing we’ve already mentioned.
There we define a `Folder` and call `fold_with` on the `TypeFoldable` to process yourself.
Then [fold_ty] the method that process each type it looks for a `ty::Param` and for those
it replaces it for something from the list of substitutions, otherwise recursively process the type.
To replace it, calls [ty_for_param]
and all that does is index into the list of substitutions with the index of the `Param`.
[a previous chapter]: ty_module/instantiating_binders.md
[`TypeFoldable`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/trait.TypeFoldable.html
[`TypeFolder`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/trait.TypeFolder.html
[`fold_ty`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_middle/ty/trait.TypeFolder.html#method.fold_ty
[`ArgFolder`]: https://doc.rust-lang.org/nightly/nightly-rustc/rustc_type_ir/binder/struct.ArgFolder.html
[here]: https://github.com/rust-lang/rust/blob/master/compiler/rustc_macros/src/type_foldable.rs
[actual folder]: https://github.com/rust-lang/rust/blob/75ff3110ac6d8a0259023b83fd20d7ab295f8dd6/src/librustc_middle/ty/subst.rs#L440-L451
[fold_ty]: https://github.com/rust-lang/rust/blob/75ff3110ac6d8a0259023b83fd20d7ab295f8dd6/src/librustc_middle/ty/subst.rs#L512-L536
[ty_for_param]: https://github.com/rust-lang/rust/blob/75ff3110ac6d8a0259023b83fd20d7ab295f8dd6/src/librustc_middle/ty/subst.rs#L552-L587