Remove trival impl Clean for CrateNum

Author: jyn514

src/librustdoc/clean/mod.rs

@@ -14,7 +14,7 @@ use rustc_attr as attr;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
-use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
+use rustc_hir::def_id::{DefId, CRATE_DEF_INDEX, LOCAL_CRATE};
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_infer::infer::region_constraints::{Constraint, RegionConstraintData};
 use rustc_middle::middle::resolve_lifetime as rl;
@@ -85,12 +85,6 @@ impl<T: Clean<U>, U> Clean<Option<U>> for Option<T> {
     }
 }
 
-impl Clean<ExternalCrate> for CrateNum {
-    fn clean(&self, _cx: &mut DocContext<'_>) -> ExternalCrate {
-        ExternalCrate { crate_num: *self }
-    }
-}
-
 impl Clean<Item> for doctree::Module<'_> {
     fn clean(&self, cx: &mut DocContext<'_>) -> Item {
         let mut items: Vec<Item> = vec![];

src/librustdoc/clean/types.rs

@@ -133,7 +133,7 @@ crate struct TraitWithExtraInfo {
     crate is_notable: bool,
 }
 
-#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Copy, Clone, Debug)]
 crate struct ExternalCrate {
     crate crate_num: CrateNum,
 }

src/librustdoc/clean/utils.rs

@@ -39,7 +39,7 @@ crate fn krate(cx: &mut DocContext<'_>) -> Crate {
         // Analyze doc-reachability for extern items
         LibEmbargoVisitor::new(cx).visit_lib(cnum);
     }
-    externs.sort_unstable();
+    externs.sort_unstable_by_key(|e| e.crate_num);
 
     // Clean the crate, translating the entire librustc_ast AST to one that is
     // understood by rustdoc.
@@ -61,7 +61,7 @@ crate fn krate(cx: &mut DocContext<'_>) -> Crate {
         _ => unreachable!(),
     }
 
-    let local_crate = LOCAL_CRATE.clean(cx);
+    let local_crate = ExternalCrate { crate_num: LOCAL_CRATE };
     let src = local_crate.src(cx.tcx);
     let name = local_crate.name(cx.tcx);
     let primitives = local_crate.primitives(cx.tcx);