clippy::complexity fixes

filter_next
needless_question_mark
bind_instead_of_map
manual_find
derivable_impls
map_identity
redundant_slicing
skip_while_next
unnecessary_unwrap
needless_bool

compiler/rustc_borrowck/src/lib.rs

@@ -2059,12 +2059,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     ) -> Option<InitIndex> {
         let mpi = self.move_data.rev_lookup.find_local(local);
         let ii = &self.move_data.init_path_map[mpi];
-        for &index in ii {
-            if flow_state.ever_inits.contains(index) {
-                return Some(index);
-            }
-        }
-        None
+        ii.into_iter().find(|&&index| flow_state.ever_inits.contains(index)).copied()
     }
 
     /// Adds the place into the used mutable variables set