tx: fix the number of pages is not incorrectly counted

allocate_test.go

@@ -0,0 +1,30 @@
+package bolt
+
+import (
+	"testing"
+)
+
+func TestTx_allocatePageStats(t *testing.T) {
+	f := newFreelist()
+	f.ids = []pgid{2, 3}
+
+	tx := &Tx{
+		db: &DB{
+			freelist: f,
+			pageSize: defaultPageSize,
+		},
+		meta:  &meta{},
+		pages: make(map[pgid]*page),
+	}
+
+	prePageCnt := tx.Stats().PageCount
+	allocateCnt := f.free_count()
+
+	if _, err := tx.allocate(allocateCnt); err != nil {
+		t.Fatal(err)
+	}
+
+	if tx.Stats().PageCount != prePageCnt+allocateCnt {
+		t.Errorf("Allocated %d but got %d page in stats", allocateCnt, tx.Stats().PageCount)
+	}
+}

tx.go

@@ -483,7 +483,7 @@ func (tx *Tx) allocate(count int) (*page, error) {
 	tx.pages[p.id] = p
 
 	// Update statistics.
-	tx.stats.PageCount++
+	tx.stats.PageCount += count
 	tx.stats.PageAlloc += count * tx.db.pageSize
 
 	return p, nil