fix of bug with removed keys in processDeque (#30)

* removed potential bug with removed keys in processDeque

* adjust ProcessDeque test in order to catch bug with removedkv

internal/store.go

@@ -12,9 +12,10 @@ import (
 	"sync/atomic"
 	"time"
 
-	"github.com/Yiling-J/theine-go/internal/bf"
 	"github.com/gammazero/deque"
 	"github.com/zeebo/xxh3"
+
+	"github.com/Yiling-J/theine-go/internal/bf"
 )
 
 const (
@@ -369,7 +370,6 @@ func (s *Store[K, V]) processDeque(shard *Shard[K, V]) {
 	removedkv := make([]dequeKV[K, V], 0, 2)
 	// expired
 	expiredkv := make([]dequeKV[K, V], 0, 2)
-	// expired
 	for shard.qlen > int(shard.qsize) {
 		evicted := shard.deque.PopBack()
 		evicted.deque = false
@@ -394,9 +394,7 @@ func (s *Store[K, V]) processDeque(shard *Shard[K, V]) {
 					deleted := shard.delete(evicted)
 					// double check because entry maybe removed already by Delete API
 					if deleted {
-						removedkv = append(
-							expiredkv, s.kvBuilder(evicted),
-						)
+						removedkv = append(removedkv, s.kvBuilder(evicted))
 						s.postDelete(evicted)
 					}
 				}

internal/store_test.go

@@ -62,6 +62,20 @@ func TestProcessDeque(t *testing.T) {
 		keys = append(keys, e.key)
 	}
 	require.Equal(t, []int{3, 4, 123}, keys)
+	require.Equal(t, 0, len(evicted))
+
+	// test evicted callback, cost less than threshold will be evicted immediately
+	store.policy.threshold.Store(100)
+	for i := 10; i < 15; i++ {
+		entry := &Entry[int, int]{key: i}
+		entry.cost.Store(1)
+		store.shards[index].deque.PushFront(entry)
+		store.shards[index].qlen += 1
+		store.shards[index].hashmap[i] = entry
+	}
+	store.shards[index].mu.Lock()
+	store.processDeque(store.shards[index])
+	require.Equal(t, 5, len(evicted))
 }
 
 func TestRemoveDeque(t *testing.T) {