Clean up code a bit:

 * Remove "bool_to_options" feature
 * Update version for compiler feature
 * rustfmt

Author: GuillaumeGomez

compiler/rustc_feature/src/active.rs

@@ -676,7 +676,7 @@ declare_features! (
     (active, closure_track_caller, "1.57.0", Some(87417), None),
 
     /// Allows `#[doc(cfg_hide(...))]`.
-    (active, doc_cfg_hide, "1.53.0", Some(43781), None),
+    (active, doc_cfg_hide, "1.57.0", Some(43781), None),
 
     // -------------------------------------------------------------------------
     // feature-group-end: actual feature gates

library/alloc/src/lib.rs

@@ -65,9 +65,10 @@
 #![doc(
     html_playground_url = "https://play.rust-lang.org/",
     issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/",
-    test(no_crate_inject, attr(allow(unused_variables), deny(warnings))),
+    test(no_crate_inject, attr(allow(unused_variables), deny(warnings)))
 )]
-#![cfg_attr(not(bootstrap),
+#![cfg_attr(
+    not(bootstrap),
     doc(cfg_hide(not(test), not(any(test, bootstrap)), target_has_atomic = "ptr"))
 )]
 #![no_std]

library/core/src/lib.rs

@@ -58,9 +58,10 @@
     html_playground_url = "https://play.rust-lang.org/",
     issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/",
     test(no_crate_inject, attr(deny(warnings))),
-    test(attr(allow(dead_code, deprecated, unused_variables, unused_mut))),
+    test(attr(allow(dead_code, deprecated, unused_variables, unused_mut)))
 )]
-#![cfg_attr(not(bootstrap),
+#![cfg_attr(
+    not(bootstrap),
     doc(cfg_hide(
         not(test),
         target_pointer_width = "16",

library/std/src/lib.rs

@@ -193,11 +193,9 @@
     html_playground_url = "https://play.rust-lang.org/",
     issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/",
     test(no_crate_inject, attr(deny(warnings))),
-    test(attr(allow(dead_code, deprecated, unused_variables, unused_mut))),
-)]
-#![cfg_attr(not(bootstrap),
-    doc(cfg_hide(not(test), not(any(test, bootstrap))))
+    test(attr(allow(dead_code, deprecated, unused_variables, unused_mut)))
 )]
+#![cfg_attr(not(bootstrap), doc(cfg_hide(not(test), not(any(test, bootstrap)))))]
 // Don't link to std. We are std.
 #![no_std]
 #![warn(deprecated_in_future)]

src/librustdoc/clean/types.rs

@@ -786,7 +786,9 @@ impl AttributesExt for [ast::Attribute] {
             fn single(self) -> Option<Self::Item> {
                 let mut iter = self.into_iter();
                 let item = iter.next()?;
-                iter.next().is_none().then_some(())?;
+                if iter.next().is_some() {
+                    return None;
+                }
                 Some(item)
             }
         }
@@ -802,16 +804,19 @@ impl AttributesExt for [ast::Attribute] {
             if doc_cfg.peek().is_some() {
                 doc_cfg
                     .filter_map(|attr| {
-                        Cfg::parse(&attr).map_err(|e| sess.diagnostic().span_err(e.span, e.msg)).ok()
+                        Cfg::parse(&attr)
+                            .map_err(|e| sess.diagnostic().span_err(e.span, e.msg))
+                            .ok()
                     })
                     .fold(Cfg::True, |cfg, new_cfg| cfg & new_cfg)
             } else {
-                self
-                    .iter()
+                self.iter()
                     .filter(|attr| attr.has_name(sym::cfg))
                     .filter_map(|attr| Some(attr.meta_item_list()?.single()?.meta_item()?.clone()))
                     .filter_map(|attr| {
-                        Cfg::parse(&attr).map_err(|e| sess.diagnostic().span_err(e.span, e.msg)).ok()
+                        Cfg::parse(&attr)
+                            .map_err(|e| sess.diagnostic().span_err(e.span, e.msg))
+                            .ok()
                     })
                     .filter(|cfg| !hidden_cfg.contains(cfg))
                     .fold(Cfg::True, |cfg, new_cfg| cfg & new_cfg)

src/librustdoc/lib.rs

@@ -5,7 +5,6 @@
 #![feature(rustc_private)]
 #![feature(array_methods)]
 #![feature(assert_matches)]
-#![feature(bool_to_option)]
 #![feature(box_patterns)]
 #![feature(control_flow_enum)]
 #![feature(box_syntax)]

src/librustdoc/visit_ast.rs

@@ -3,10 +3,10 @@
 
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
-use rustc_hir::CRATE_HIR_ID;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
 use rustc_hir::Node;
+use rustc_hir::CRATE_HIR_ID;
 use rustc_middle::middle::privacy::AccessLevel;
 use rustc_middle::ty::TyCtxt;
 use rustc_span;
@@ -99,7 +99,11 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             }
         }
 
-        self.cx.cache.hidden_cfg = self.cx.tcx.hir().attrs(CRATE_HIR_ID)
+        self.cx.cache.hidden_cfg = self
+            .cx
+            .tcx
+            .hir()
+            .attrs(CRATE_HIR_ID)
             .iter()
             .filter(|attr| attr.has_name(sym::doc))
             .flat_map(|attr| attr.meta_item_list().into_iter().flatten())