Added a test for file rotation

client/driver/logs.go

@@ -24,7 +24,7 @@ func NewLogRotor(path string, fileName string, maxFiles int, fileSize int64) (*L
 		return nil, err
 	}
 
-	logFileIdx := 0
+	logFileIdx := 1
 	for _, f := range files {
 		if strings.HasPrefix(f.Name(), fileName) {
 			fileIdx := strings.TrimPrefix(f.Name(), fmt.Sprintf("%s.", fileName))

client/driver/logs_test.go

@@ -1,6 +1,7 @@
 package driver
 
 import (
+	"bytes"
 	"os"
 	"path/filepath"
 	"testing"
@@ -19,6 +20,7 @@ func TestLogRotator_FindCorrectIndex(t *testing.T) {
 	if err := os.Mkdir(path, os.ModeDir|os.ModePerm); err != nil {
 		t.Fatalf("test setup err: %v", err)
 	}
+	defer os.RemoveAll(path)
 
 	fname := filepath.Join(path, "redis.stdout.1")
 	if f, err := os.Create(fname); err == nil {
@@ -38,3 +40,24 @@ func TestLogRotator_FindCorrectIndex(t *testing.T) {
 		t.Fatalf("Expected log file idx: %v, actual: %v", 2, r.logFileIdx)
 	}
 }
+
+func TestLogRotator_AppendToCurrentFile(t *testing.T) {
+	path := "/tmp/tmplogrator"
+	if err := os.Mkdir(path, os.ModeDir|os.ModePerm); err != nil {
+		t.Fatalf("test setup err: %v", err)
+	}
+	defer os.RemoveAll(path)
+	fname := filepath.Join(path, "redis.stdout.1")
+	if f, err := os.Create(fname); err == nil {
+		f.Close()
+	}
+
+	r, err := NewLogRotor(path, "redis.stdout", 10, 10)
+	if err != nil {
+		t.Fatalf("test setup err: %v", err)
+	}
+
+	var buf bytes.Buffer
+	buf.WriteString("hello")
+	r.Start(&buf)
+}