remove uncessary parens in closure body in tools

Author: chenyukang

src/tools/clippy/clippy_lints/src/unused_async.rs

@@ -165,7 +165,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedAsync {
         let iter = self
             .unused_async_fns
             .iter()
-            .filter(|UnusedAsyncFn { def_id, .. }| (!self.async_fns_as_value.contains(def_id)));
+            .filter(|UnusedAsyncFn { def_id, .. }| !self.async_fns_as_value.contains(def_id));
 
         for fun in iter {
             span_lint_hir_and_then(

src/tools/clippy/clippy_utils/src/higher.rs

@@ -172,7 +172,7 @@ impl<'hir> IfLetOrMatch<'hir> {
                      if_then,
                      if_else,
                      let_span,
-                 }| { Self::IfLet(let_expr, let_pat, if_then, if_else, let_span) },
+                 }| Self::IfLet(let_expr, let_pat, if_then, if_else, let_span),
             ),
         }
     }

src/tools/clippy/clippy_utils/src/ty/mod.rs

@@ -927,7 +927,7 @@ impl AdtVariantInfo {
                     .enumerate()
                     .map(|(i, f)| (i, approx_ty_size(cx, f.ty(cx.tcx, subst))))
                     .collect::<Vec<_>>();
-                fields_size.sort_by(|(_, a_size), (_, b_size)| (a_size.cmp(b_size)));
+                fields_size.sort_by(|(_, a_size), (_, b_size)| a_size.cmp(b_size));
 
                 Self {
                     ind: i,
@@ -936,7 +936,7 @@ impl AdtVariantInfo {
                 }
             })
             .collect::<Vec<_>>();
-        variants_size.sort_by(|a, b| (b.size.cmp(&a.size)));
+        variants_size.sort_by(|a, b| b.size.cmp(&a.size));
         variants_size
     }
 }

src/tools/miri/src/concurrency/thread.rs

@@ -641,7 +641,7 @@ impl<'tcx> ThreadManager<'tcx> {
         assert!(
             self.threads
                 .iter()
-                .all(|thread| { !thread.state.is_blocked_on(BlockReason::Join(joined_thread_id)) }),
+                .all(|thread| !thread.state.is_blocked_on(BlockReason::Join(joined_thread_id))),
             "this thread already has threads waiting for its termination"
         );