backport of commit c34cb8e

.changelog/13658.txt

@@ -1,3 +1,3 @@
 ```release-note:improvement
-cli: `operator snapshot state` supports `-filter` expressions and stream decompresses snapshots to avoid writing large temporary files
+cli: `operator snapshot state` supports `-filter` expressions and avoids writing large temporary files
 ```

helper/raftutil/snapshot.go

@@ -30,8 +30,7 @@ func RestoreFromArchive(archive io.Reader, filter *nomad.FSMFilter) (*state.Stat
 		meta, err := snapshot.CopySnapshot(archive, w)
 		if err != nil {
 			errCh <- fmt.Errorf("failed to read snapshot: %w", err)
-		}
-		if meta != nil {
+		} else {
 			metaCh <- meta
 		}
 	}()

nomad/fsm.go

@@ -1490,8 +1490,7 @@ func (n *nomadFSM) restoreImpl(old io.ReadCloser, filter *FSMFilter) error {
 				/* Handle upgrade paths:
 				 * - Empty maps and slices should be treated as nil to avoid
 				 *   un-intended destructive updates in scheduler since we use
-				 *   reflect.DeepEqual. Starting Nomad 0.4.1, job submission sanitizes
-				 *   the incoming job.
+				 *   reflect.DeepEqual. Job submission sanitizes the incoming job.
 				 * - Migrate from old style upgrade stanza that used only a stagger.
 				 */
 				job.Canonicalize()