fix: panic runtime error: index out of range [7] with length 0 (#288)

bigcache_test.go

@@ -1091,3 +1091,44 @@ func (mc *mockedClock) set(value int64) {
 func blob(char byte, len int) []byte {
 	return bytes.Repeat([]byte{char}, len)
 }
+
+//
+func TestCache_RepeatedSetWithBiggerEntry(t *testing.T) {
+
+	opt := DefaultConfig(time.Second)
+	opt.Shards = 2 << 10
+	opt.MaxEntriesInWindow = 1024
+	opt.MaxEntrySize = 1
+	opt.HardMaxCacheSize = 1
+	bc, _ := NewBigCache(opt)
+
+	err := bc.Set("2225", make([]byte, 200))
+	if nil != err {
+		t.Error(err)
+		t.FailNow()
+	}
+	err = bc.Set("8573", make([]byte, 100))
+	if nil != err {
+		t.Error(err)
+		t.FailNow()
+	}
+
+	err = bc.Set("8573", make([]byte, 450))
+	if nil != err {
+		// occur error but go next
+		t.Logf("%v", err)
+	}
+
+	err = bc.Set("7327", make([]byte, 300))
+	if nil != err {
+		t.Error(err)
+		t.FailNow()
+	}
+
+	err = bc.Set("8573", make([]byte, 200))
+	if nil != err {
+		t.Error(err)
+		t.FailNow()
+	}
+
+}

shard.go

@@ -125,6 +125,8 @@ func (s *cacheShard) set(key string, hashedKey uint64, entry []byte) error {
 	if previousIndex := s.hashmap[hashedKey]; previousIndex != 0 {
 		if previousEntry, err := s.entries.Get(int(previousIndex)); err == nil {
 			resetKeyFromEntry(previousEntry)
+			//remove hashkey
+			delete(s.hashmap, hashedKey)
 		}
 	}