Rustfmt now support use closures

[spastorino]

This should be merged when rust-lang/rustfmt#6532 is used by CI's rustfmt.

[rustbot]

r? @Mark-Simulacrum

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[rust-log-analyzer]

The job mingw-check-tidy failed! Check out the build log: (web) (plain)

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info: removing rustup binaries
info: rustup is uninstalled
##[group]Image checksum input
mingw-check-tidy
# We use the ghcr base image because ghcr doesn't have a rate limit
# and the mingw-check-tidy job doesn't cache docker images in CI.
FROM ghcr.io/rust-lang/ubuntu:22.04

ARG DEBIAN_FRONTEND=noninteractive
RUN apt-get update && apt-get install -y --no-install-recommends \
  g++ \
  make \
---

COPY host-x86_64/mingw-check/validate-toolstate.sh /scripts/
COPY host-x86_64/mingw-check/validate-error-codes.sh /scripts/

# NOTE: intentionally uses python2 for x.py so we can test it still works.
# validate-toolstate only runs in our CI, so it's ok for it to only support python3.
ENV SCRIPT TIDY_PRINT_DIFF=1 python2.7 ../x.py test \
           --stage 0 src/tools/tidy tidyselftest --extra-checks=py,cpp
#
# This file is autogenerated by pip-compile with Python 3.10
# by the following command:
#
#    pip-compile --allow-unsafe --generate-hashes reuse-requirements.in
---
#12 3.237 Building wheels for collected packages: reuse
#12 3.238   Building wheel for reuse (pyproject.toml): started
#12 3.450   Building wheel for reuse (pyproject.toml): finished with status 'done'
#12 3.451   Created wheel for reuse: filename=reuse-4.0.3-cp310-cp310-manylinux_2_35_x86_64.whl size=132719 sha256=5bb60f62728aaedff7162745ce743c7f2f55069b3e7f82e6a37d70df455797cc
#12 3.451   Stored in directory: /tmp/pip-ephem-wheel-cache-0idy3_en/wheels/3d/8d/0a/e0fc6aba4494b28a967ab5eaf951c121d9c677958714e34532
#12 3.454 Successfully built reuse
#12 3.454 Installing collected packages: boolean-py, binaryornot, tomlkit, reuse, python-debian, markupsafe, license-expression, jinja2, chardet, attrs
#12 3.876 Successfully installed attrs-23.2.0 binaryornot-0.4.4 boolean-py-4.0 chardet-5.2.0 jinja2-3.1.4 license-expression-30.3.0 markupsafe-2.1.5 python-debian-0.1.49 reuse-4.0.3 tomlkit-0.13.0
#12 3.877 WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
#12 4.442 Collecting virtualenv
#12 4.505   Downloading virtualenv-20.30.0-py3-none-any.whl (4.3 MB)
#12 4.595      ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 4.3/4.3 MB 49.8 MB/s eta 0:00:00
#12 4.660 Collecting filelock<4,>=3.12.2
#12 4.672   Downloading filelock-3.18.0-py3-none-any.whl (16 kB)
#12 4.712 Collecting platformdirs<5,>=3.9.1
#12 4.725   Downloading platformdirs-4.3.7-py3-none-any.whl (18 kB)
#12 4.749 Collecting distlib<1,>=0.3.7
#12 4.761   Downloading distlib-0.3.9-py2.py3-none-any.whl (468 kB)
#12 4.768      ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 469.0/469.0 KB 95.9 MB/s eta 0:00:00
#12 4.850 Installing collected packages: distlib, platformdirs, filelock, virtualenv
#12 5.035 Successfully installed distlib-0.3.9 filelock-3.18.0 platformdirs-4.3.7 virtualenv-20.30.0
#12 5.036 WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
#12 DONE 5.1s

#13 [7/8] COPY host-x86_64/mingw-check/validate-toolstate.sh /scripts/
#13 DONE 0.0s
---
DirectMap4k:      131008 kB
DirectMap2M:     6160384 kB
DirectMap1G:    12582912 kB
##[endgroup]
Executing TIDY_PRINT_DIFF=1 python2.7 ../x.py test            --stage 0 src/tools/tidy tidyselftest --extra-checks=py,cpp
+ TIDY_PRINT_DIFF=1 python2.7 ../x.py test --stage 0 src/tools/tidy tidyselftest --extra-checks=py,cpp
##[group]Building bootstrap
    Finished `dev` profile [unoptimized] target(s) in 0.05s
##[endgroup]
WARN: currently no CI rustc builds have rustc debug assertions enabled. Please either set `rust.debug-assertions` to `false` if you want to use download CI rustc or set `rust.download-rustc` to `false`.
[TIMING] core::build_steps::tool::LibcxxVersionTool { target: x86_64-unknown-linux-gnu } -- 0.224
---
##[endgroup]
[TIMING] core::build_steps::tool::ToolBuild { compiler: Compiler { stage: 0, host: x86_64-unknown-linux-gnu, forced_compiler: false }, target: x86_64-unknown-linux-gnu, tool: "tidy", path: "src/tools/tidy", mode: ToolBootstrap, source_type: InTree, extra_features: [], allow_features: "", cargo_args: [], artifact_kind: Binary } -- 36.960
[TIMING] core::build_steps::tool::Tidy { compiler: Compiler { stage: 0, host: x86_64-unknown-linux-gnu, forced_compiler: false }, target: x86_64-unknown-linux-gnu } -- 0.000
fmt check
Diff in /checkout/tests/mir-opt/ergonomic-clones/closure.rs:10:
     // CHECK-NOT: <String as Clone>::clone
     let s = String::from("hi");
 
-    let cl = use || s;
+    let cl = || s;
     cl()
 }
 
Diff in /checkout/tests/mir-opt/ergonomic-clones/closure.rs:24:
     // CHECK: <Foo as Clone>::clone
     let f = Foo;
 
-    let f1 = use || f;
+    let f1 = || f;
 
-    let f2 = use || f;
+    let f2 = || f;
 
     f
 }
Diff in /checkout/tests/mir-opt/ergonomic-clones/closure.rs:37:
     // CHECK-NOT: <i32 as Clone>::clone
     let i = 1;
 
-    let i1 = use || i;
+    let i1 = || i;
 
-    let i2 = use || i;
+    let i2 = || i;
 
     i
 }
Diff in /checkout/tests/mir-opt/ergonomic-clones/closure.rs:47:
 pub fn ergonomic_clone_closure_use_cloned_generics<T: UseCloned>(f: T) -> T {
     // CHECK-LABEL: fn ergonomic_clone_closure_use_cloned_generics(
     // CHECK: <T as Clone>::clone
-    let f1 = use || f;
+    let f1 = || f;
 
-    let f2 = use || f;
+    let f2 = || f;
 
     f
 }
Diff in /checkout/tests/codegen/ergonomic-clones/closure.rs:1:
 //@ compile-flags: -C no-prepopulate-passes -Copt-level=0 -Zmir-opt-level=0
 
 #![crate_type = "lib"]
-
 #![feature(ergonomic_clones)]
 #![allow(incomplete_features)]
 
Diff in /checkout/tests/codegen/ergonomic-clones/closure.rs:11:
     let s = String::from("hi");
 
     // CHECK-NOT: ; call core::clone::impls::<impl core::clone::Clone for String>::clone
-    let cl = use || s;
+    let cl = || s;
     cl()
 }
 
Diff in /checkout/tests/codegen/ergonomic-clones/closure.rs:24:
     let f = Foo;
 
     // CHECK: ; call <closure::Foo as core::clone::Clone>::clone
-    let f1 = use || f;
+    let f1 = || f;
 
     // CHECK: ; call <closure::Foo as core::clone::Clone>::clone
-    let f2 = use || f;
+    let f2 = || f;
 
     f
 }
Diff in /checkout/tests/codegen/ergonomic-clones/closure.rs:36:
     let i = 1;
---
     i
 }
Diff in /checkout/tests/codegen/ergonomic-clones/closure.rs:46:
 
 pub fn ergonomic_clone_closure_use_cloned_generics<T: UseCloned>(f: T) -> T {
     // CHECK-NOT: ; call core::clone::impls::<impl core::clone::Clone for i32>::clone
-    let f1 = use || f;
+    let f1 = || f;
 
     // CHECK-NOT: ; call core::clone::impls::<impl core::clone::Clone for i32>::clone
-    let f2 = use || f;
+    let f2 = || f;
 
     f
 }
fmt: checked 5984 files
Build completed unsuccessfully in 0:01:18