address comment

Signed-off-by: linning <linningde25@gmail.com>

components/raftstore/src/store/peer.rs

@@ -992,10 +992,11 @@ where
             PeerState::Tombstone,
             // Only persist the `merge_state` if the merge is known to be succeeded
             // which is determined by the `keep_data` flag
-            self.pending_merge_state
-                .as_ref()
-                .filter(|_| keep_data)
-                .cloned(),
+            if keep_data {
+                self.pending_merge_state.clone()
+            } else {
+                None
+            },
         )?;
         // write kv rocksdb first in case of restart happen between two write
         let mut write_opts = WriteOptions::new();

tests/failpoints/cases/test_merge.rs

@@ -1676,10 +1676,7 @@ fn test_destroy_source_peer_while_merging() {
     let pd_client = Arc::clone(&cluster.pd_client);
     pd_client.disable_default_operator();
 
-    let r1 = cluster.run_conf_change();
-    for i in 2..=5 {
-        pd_client.must_add_peer(r1, new_peer(i, i));
-    }
+    cluster.run();
 
     cluster.must_put(b"k1", b"v1");
     cluster.must_put(b"k3", b"v3");
@@ -1729,7 +1726,6 @@ fn test_destroy_source_peer_while_merging() {
     // but it is still in tombstone state due to the message filter
     let state = cluster.region_local_state(right.get_id(), 5);
     assert_eq!(state.get_state(), PeerState::Tombstone);
-    assert!(!state.has_merge_state(), "{:?}", state);
 
     // let the peer on store 4 have a larger peer id
     pd_client.must_remove_peer(right.get_id(), new_peer(4, 4));
@@ -1743,6 +1739,7 @@ fn test_destroy_source_peer_while_merging() {
     cluster.add_send_filter(IsolationFilterFactory::new(1));
 
     cluster.must_put(b"k5", b"v5");
+    assert!(!state.has_merge_state(), "{:?}", state);
     for i in 2..=5 {
         must_get_equal(&cluster.get_engine(i), b"k5", b"v5");
     }