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 enhanced) (plain)

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##[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 } -- 8.715
[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/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
 }
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 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
 }
fmt: checked 6137 files
Build completed unsuccessfully in 0:00:46