Used clippy to clean itself

clippy_lints/src/methods/mod.rs

@@ -2461,11 +2461,7 @@ fn derefs_to_slice<'tcx>(
             ty::Adt(def, _) if def.is_box() => may_slice(cx, ty.boxed_ty()),
             ty::Adt(..) => is_type_diagnostic_item(cx, ty, sym!(vec_type)),
             ty::Array(_, size) => {
-                if let Some(size) = size.try_eval_usize(cx.tcx, cx.param_env) {
-                    size < 32
-                } else {
-                    false
-                }
+                size.try_eval_usize(cx.tcx, cx.param_env).map_or(false, |size| size < 32)
             },
             ty::Ref(_, inner, _) => may_slice(cx, inner),
             _ => false,

clippy_lints/src/methods/unnecessary_filter_map.rs

@@ -78,11 +78,7 @@ fn check_expression<'tcx>(cx: &LateContext<'tcx>, arg_id: hir::HirId, expr: &'tc
             (true, true)
         },
         hir::ExprKind::Block(ref block, _) => {
-            if let Some(expr) = &block.expr {
-                check_expression(cx, arg_id, &expr)
-            } else {
-                (false, false)
-            }
+            block.expr.as_ref().map_or((false, false), |expr| check_expression(cx, arg_id, &expr))
         },
         hir::ExprKind::Match(_, arms, _) => {
             let mut found_mapping = false;