Remove some unnecessary unwraps

Author: estebank

compiler/rustc_hir_typeck/src/fn_ctxt/suggestions.rs

@@ -604,8 +604,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             return false;
         }
         let box_found = Ty::new_box(self.tcx, found);
-        let pin_box_found = Ty::new_lang_item(self.tcx, box_found, LangItem::Pin).unwrap();
-        let pin_found = Ty::new_lang_item(self.tcx, found, LangItem::Pin).unwrap();
+        let Some(pin_box_found) = Ty::new_lang_item(self.tcx, box_found, LangItem::Pin) else {
+            return false;
+        };
+        let Some(pin_found) = Ty::new_lang_item(self.tcx, found, LangItem::Pin) else {
+            return false;
+        };
         match expected.kind() {
             ty::Adt(def, _) if Some(def.did()) == pin_did => {
                 if self.can_coerce(pin_box_found, expected) {

compiler/rustc_hir_typeck/src/method/suggest.rs

@@ -1616,7 +1616,11 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         continue;
                     }
 
-                    let range_def_id = self.tcx.require_lang_item(lang_item.unwrap(), None);
+                    let Some(range_def_id) =
+                        lang_item.and_then(|lang_item| self.tcx.lang_items().get(lang_item))
+                    else {
+                        continue;
+                    };
                     let range_ty =
                         self.tcx.type_of(range_def_id).instantiate(self.tcx, &[actual.into()]);
 
@@ -2539,11 +2543,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     Err(_) => (),
                 }
 
-                let pred = ty::TraitRef::new(
-                    self.tcx,
-                    self.tcx.lang_items().unpin_trait().unwrap(),
-                    [*rcvr_ty],
-                );
+                let Some(unpin_trait) = self.tcx.lang_items().unpin_trait() else {
+                    return;
+                };
+                let pred = ty::TraitRef::new(self.tcx, unpin_trait, [*rcvr_ty]);
                 let unpin = self.predicate_must_hold_considering_regions(&Obligation::new(
                     self.tcx,
                     ObligationCause::misc(rcvr.span, self.body_id),

compiler/rustc_lint/src/unused.rs

@@ -353,7 +353,9 @@ impl<'tcx> LateLintPass<'tcx> for UnusedResults {
                 ty::Generator(def_id, ..) => {
                     // async fn should be treated as "implementor of `Future`"
                     let must_use = if cx.tcx.generator_is_async(def_id) {
-                        let def_id = cx.tcx.lang_items().future_trait().unwrap();
+                        let Some(def_id) = cx.tcx.lang_items().future_trait() else {
+                            return None;
+                        };
                         is_def_must_use(cx, def_id, span)
                             .map(|inner| MustUsePath::Opaque(Box::new(inner)))
                     } else {