refactor: Statistics check for nil in its methods (#529)

nodedb.go

@@ -116,15 +116,11 @@ func (ndb *nodeDB) GetNode(hash []byte) (*Node, error) {
 
 	// Check the cache.
 	if cachedNode := ndb.nodeCache.Get(hash); cachedNode != nil {
-		if ndb.opts.Stat != nil {
-			ndb.opts.Stat.IncCacheHitCnt()
-		}
+		ndb.opts.Stat.IncCacheHitCnt()
 		return cachedNode.(*Node), nil
 	}
 
-	if ndb.opts.Stat != nil {
-		ndb.opts.Stat.IncCacheMissCnt()
-	}
+	ndb.opts.Stat.IncCacheMissCnt()
 
 	// Doesn't exist, load.
 	buf, err := ndb.db.Get(ndb.nodeKey(hash))
@@ -160,15 +156,11 @@ func (ndb *nodeDB) GetFastNode(key []byte) (*FastNode, error) {
 	}
 
 	if cachedFastNode := ndb.fastNodeCache.Get(key); cachedFastNode != nil {
-		if ndb.opts.Stat != nil {
-			ndb.opts.Stat.IncFastCacheHitCnt()
-		}
+		ndb.opts.Stat.IncFastCacheHitCnt()
 		return cachedFastNode.(*FastNode), nil
 	}
 
-	if ndb.opts.Stat != nil {
-		ndb.opts.Stat.IncFastCacheMissCnt()
-	}
+	ndb.opts.Stat.IncFastCacheMissCnt()
 
 	// Doesn't exist, load.
 	buf, err := ndb.db.Get(ndb.fastNodeKey(key))

options.go

@@ -18,18 +18,30 @@ type Statistics struct {
 }
 
 func (stat *Statistics) IncCacheHitCnt() {
+	if stat == nil {
+		return
+	}
 	atomic.AddUint64(&stat.cacheHitCnt, 1)
 }
 
 func (stat *Statistics) IncCacheMissCnt() {
+	if stat == nil {
+		return
+	}
 	atomic.AddUint64(&stat.cacheMissCnt, 1)
 }
 
 func (stat *Statistics) IncFastCacheHitCnt() {
+	if stat == nil {
+		return
+	}
 	atomic.AddUint64(&stat.fastCacheHitCnt, 1)
 }
 
 func (stat *Statistics) IncFastCacheMissCnt() {
+	if stat == nil {
+		return
+	}
 	atomic.AddUint64(&stat.fastCacheMissCnt, 1)
 }