diff --git a/README.md b/README.md
index 62bc80a..66d1ce4 100644
--- a/README.md
+++ b/README.md
@@ -245,7 +245,7 @@ func TestEnvBind(t *testing.T) {
 	Convey("env bind", t, func(c C) {
 		cc := &Config{}
 		x := xconf.NewWithoutFlagEnv()
-		x.UpdateWithFieldPathValues("http_address", "${XCONF_HOST}:${XCONF_PORT}")
+		So(x.UpdateWithFieldPathValues("http_address", "${XCONF_HOST}:${XCONF_PORT}"),ShouldBeNil)
 		err := x.Parse(cc)
 		So(err, ShouldBeNil)
 		So(cc.HttpAddress, ShouldEqual, "")
@@ -324,7 +324,7 @@ var atomicConfig unsafe.Pointer
 func AtomicConfigSet(update interface{}) {
 	atomic.StorePointer(&atomicConfig, (unsafe.Pointer)(update.(*Config)))
 }
-func AtomicConfig() *Config {
+func AtomicConfig() ConfigVisitor {
 	current := (*Config)(atomic.LoadPointer(&atomicConfig))
 	if current == nil {
 		atomic.CompareAndSwapPointer(&atomicConfig, nil, (unsafe.Pointer)(newDefaultConfig()))
diff --git a/merge.go b/merge.go
index bf869de..de2fe0f 100644
--- a/merge.go
+++ b/merge.go
@@ -106,22 +106,23 @@ func mergeMap(
 			}
 			logger(fmt.Sprintf("%s%s is leaf key, overide.\n", indentNow, fieldPath))
 		} else {
+			var mergeErr error
 			switch dstValType := dstVal.(type) {
 			case map[interface{}]interface{}:
 				logger(fmt.Sprintf("%s%s dstVal is map[interface{}]interface{}, merge deep.\n", indentNow, fieldPath))
 				tsv := srcVal.(map[interface{}]interface{})
 				ssv := castToMapStringInterface(tsv)
 				stv := castToMapStringInterface(dstValType)
-				mergeMap(fieldPath, depth, logger, ssv, stv, isLeafFieldPath, dstValType, changes)
+				mergeErr = mergeMap(fieldPath, depth, logger, ssv, stv, isLeafFieldPath, dstValType, changes)
 			case map[string]interface{}:
 				switch srcValType := srcVal.(type) {
 				case map[interface{}]interface{}:
 					logger(fmt.Sprintf("%s%s dstVal: map[string]interface{} srcVal:map[interface{}]interface{}, deep merge\n", indentNow, fieldPath))
 					ssv := castToMapStringInterface(srcValType)
-					mergeMap(fieldPath, depth, logger, ssv, dstValType, isLeafFieldPath, nil, changes)
+					mergeErr = mergeMap(fieldPath, depth, logger, ssv, dstValType, isLeafFieldPath, nil, changes)
 				case map[string]interface{}:
 					logger(fmt.Sprintf("%s%s dstVal: map[string]interface{} srcVal:map[string]interface{}, deep merge\n", indentNow, fieldPath))
-					mergeMap(fieldPath, depth, logger, srcValType, dstValType, isLeafFieldPath, nil, changes)
+					mergeErr = mergeMap(fieldPath, depth, logger, srcValType, dstValType, isLeafFieldPath, nil, changes)
 				default:
 					dst[dstKey] = srcVal
 					if changes != nil {
@@ -142,6 +143,9 @@ func mergeMap(
 				}
 				logger(fmt.Sprintf("%s%s dstVal type:%v,overide\n", indentNow, fieldPath, reflect.TypeOf(dstVal)))
 			}
+			if mergeErr != nil {
+				return fmt.Errorf("got err:%w while merge:%s", mergeErr, fieldPath)
+			}
 		}
 	}
 	return nil
diff --git a/tests/all_test.go b/tests/all_test.go
index 3f492c9..031f303 100644
--- a/tests/all_test.go
+++ b/tests/all_test.go
@@ -25,9 +25,8 @@ func TestParseWithDefaultValue(t *testing.T) {
 		xconf.WithFlagSet(flag.NewFlagSet("TestParseWithDefaultValue", flag.ContinueOnError)),
 		xconf.WithFlagArgs(),
 	)
-
-	x.Parse(cc)
 	Convey("just parse with default value", t, func(c C) {
+		So(x.Parse(cc), ShouldBeNil)
 		So(defaultVal, ShouldResemble, cc)
 	})
 }
@@ -75,7 +74,7 @@ func TestOverideDefaultValue(t *testing.T) {
 		So(cc.Map1, ShouldResemble, map[string]int{"test1": 100, "test2": 200})
 		So(cc.MapNotLeaf, ShouldResemble, map[string]int{"test1": 100, "test2": 200})
 		So(cc.Int64Slice, ShouldResemble, []int64{101, 202, 303})
-		x.Parse(cc)
+		So(x.Parse(cc), ShouldBeNil)
 
 		So(cc.HttpAddress, ShouldEqual, ":3002")
 		// map1作为叶子节点存在
@@ -110,7 +109,7 @@ func TestOverideDefaultValue(t *testing.T) {
 		cc.SubTest.Map2 = map[string]int{"test1": 11111}
 		cc.MapNotLeaf = make(map[string]int)
 		cc.MapNotLeaf["k1"] = 1111
-		x.Parse(cc)
+		So(x.Parse(cc), ShouldBeNil)
 		x.DumpInfo()
 		So(cc.HttpAddress, ShouldEqual, "192.168.0.1")
 		So(cc.Int64Slice, ShouldResemble, []int64{100, 101})
@@ -143,13 +142,11 @@ func TestWatchUpdate(t *testing.T) {
 	updated := make(chan *Config, 1)
 	go func() {
 		for {
-			select {
-			case v := <-x.NotifyUpdate():
-				updated <- v.(*Config)
-			}
+			v := <-x.NotifyUpdate()
+			updated <- v.(*Config)
 		}
 	}()
-	x.Parse(cc)
+	So(x.Parse(cc), ShouldBeNil)
 	cc.HttpAddress = "0.0.0.0"
 	bytesBuffer := bytes.NewBuffer([]byte{})
 	xconf.MustSaveVarToWriter(cc, xconf.ConfigTypeYAML, bytesBuffer)
@@ -174,8 +171,7 @@ func TestWatchUpdate(t *testing.T) {
 				fmt.Printf("sub_test.http_address changed from %v to %v ", from, to)
 			})
 			to := "123.456.789.000"
-			err := x.UpdateWithFieldPathValues(watchFieldPath, to)
-			So(err, ShouldBeNil)
+			So(x.UpdateWithFieldPathValues(watchFieldPath, to), ShouldBeNil)
 			var got *Config
 			select {
 			case got = <-updated:
@@ -188,7 +184,6 @@ func TestWatchUpdate(t *testing.T) {
 			So(got.SubTest.HTTPAddress, ShouldEqual, to)
 
 			ccHash := x.Hash()
-			So(err, ShouldBeNil)
 
 			//保存到字节流
 			x2 := xconf.NewWithoutFlagEnv(xconf.WithReaders(bytes.NewReader(x.MustAsBytes(xconf.ConfigTypeYAML))))
@@ -231,7 +226,7 @@ func TestMapMerge(t *testing.T) {
 		So(cc.Map1, ShouldResemble, map[string]int{"test1": 100, "test2": 200})
 		So(cc.MapNotLeaf, ShouldResemble, map[string]int{"test1": 100, "test2": 200})
 		So(cc.Int64Slice, ShouldResemble, []int64{101, 202, 303})
-		x.Parse(cc)
+		So(x.Parse(cc), ShouldBeNil)
 
 		So(cc.HttpAddress, ShouldEqual, ":3002")
 		So(cc.Map1, ShouldResemble, map[string]int{"test1": 1000000, "test2": 200})
@@ -311,8 +306,7 @@ func TestFlagProvider(t *testing.T) {
 			xconf.WithFlagArgs("--sub_test.servers="+jsonServer),
 		)
 		vars.SetProviderByFieldPath("sub_test.servers", newServerProvider)
-		err := x.Parse(cc)
-		So(err, ShouldBeNil)
+		So(x.Parse(cc), ShouldBeNil)
 		So(cc.SubTest.Servers["s1"].Timeouts, ShouldResemble, map[string]time.Duration{"read": time.Duration(5) * time.Second})
 	})
 }
@@ -325,8 +319,7 @@ func TestFlagProviderForEnv(t *testing.T) {
 			xconf.WithEnviron("sub_test_servers="+jsonServer),
 		)
 		vars.SetProviderByFieldPath("sub_test.servers", newServerProvider)
-		err := x.Parse(cc)
-		So(err, ShouldBeNil)
+		So(x.Parse(cc), ShouldBeNil)
 		So(cc.SubTest.Servers["s1"].Timeouts, ShouldResemble, map[string]time.Duration{"read": time.Duration(5) * time.Second})
 	})
 }
@@ -340,8 +333,7 @@ func TestFlagProviderByType(t *testing.T) {
 			xconf.WithEnviron("sub_test_servers="+jsonServer),
 		)
 		vars.SetProviderByFieldType("map[string]Server", newServerProvider)
-		err := x.Parse(cc)
-		So(err, ShouldBeNil)
+		So(x.Parse(cc), ShouldBeNil)
 		So(cc.SubTest.Servers["s1"].Timeouts, ShouldResemble, map[string]time.Duration{"read": time.Duration(5) * time.Second})
 	})
 }
@@ -373,9 +365,8 @@ func TestEnvBind(t *testing.T) {
 	Convey("env bind", t, func(c C) {
 		cc := &Config{}
 		x := xconf.NewWithoutFlagEnv()
-		x.UpdateWithFieldPathValues("http_address", "${XCONF_HOST}:${XCONF_PORT}")
-		err := x.Parse(cc)
-		So(err, ShouldBeNil)
+		So(x.UpdateWithFieldPathValues("http_address", "${XCONF_HOST}:${XCONF_PORT}"), ShouldBeNil)
+		So(x.Parse(cc), ShouldBeNil)
 		So(cc.HttpAddress, ShouldEqual, "")
 		host := "127.0.0.1"
 		port := "9001"
@@ -400,7 +391,7 @@ func TestRemoteReaderWithURL(t *testing.T) {
 	Convey("env bind", t, func(c C) {
 		cc := &Config{}
 		x := xconf.NewWithoutFlagEnv(xconf.WithReaders(xconf.NewRemoteReader("127.0.0.1:0001", time.Duration(1)*time.Second)))
-		So(func() { x.Parse(cc) }, ShouldPanic)
+		So(func() { _ = x.Parse(cc) }, ShouldPanic)
 	})
 }
 
diff --git a/tests/main/main.go b/tests/main/main.go
index 3737ef0..b80eafa 100644
--- a/tests/main/main.go
+++ b/tests/main/main.go
@@ -2,7 +2,6 @@ package main
 
 import (
 	"flag"
-	"fmt"
 	"time"
 
 	"github.com/sandwich-go/xconf"
@@ -19,9 +18,12 @@ func main() {
 	cc.SubTest.Servers["s1"] = tests.Server{
 		Timeouts: map[string]time.Duration{"read": time.Second * time.Duration(5)},
 	}
-	xconf.Parse(cc, xconf.WithDebug(true))
+	if err := xconf.Parse(cc, xconf.WithDebug(true)); err != nil {
+		panic(err)
+	}
 	x := xconf.New(xconf.WithDebug(true), xconf.WithFiles("c2.toml"), xconf.WithFlagSet(flag.NewFlagSet("test", flag.ContinueOnError)))
-	err := x.Parse(cc)
-	fmt.Println("result :", cc, err)
+	if err := x.Parse(cc); err != nil {
+		panic(err)
+	}
 	x.DumpInfo()
 }
diff --git a/xconf_reader.go b/xconf_reader.go
index a8860fd..9b3f205 100644
--- a/xconf_reader.go
+++ b/xconf_reader.go
@@ -68,9 +68,6 @@ func (r *remoteReader) do() error {
 		return fmt.Errorf("RemoteReader got invalid status code:%d", resp.StatusCode)
 	}
 	// read response content
-	buf := new(bytes.Buffer)
-	buf.ReadFrom(resp.Body)
-
 	bb, err := readAll(resp.Body)
 	if err == nil {
 		return fmt.Errorf("RemoteReader got err:%w while read body", err)
diff --git a/xconf_remote.go b/xconf_remote.go
index 6c62453..59fd1b1 100644
--- a/xconf_remote.go
+++ b/xconf_remote.go
@@ -83,5 +83,5 @@ func (x *XConf) onContentChanged(name string, confPath string, content []byte) {
 
 	panicErrWithWrap(err, "unmarshal_error(%v) ", err)
 	panicErr(x.mergeToDest(confPath, data))
-	x.notifyChanged()
+	panicErr(x.notifyChanged())
 }