mysqldef: save FSP and fix zone offset for codec

mysqldef/time.go

@@ -143,7 +143,10 @@ func (t Time) Marshal() ([]byte, error) {
 
 	switch t.Type {
 	case TypeDatetime, TypeDate:
-		_, offset := time.Now().Zone()
+		// We must use t's Zone not current Now Zone,
+		// For EDT/EST, even we create the time with time.Local location,
+		// we may still have a different zone with current Now time.
+		_, offset := t.Zone()
 		// For datetime and date type, we have a trick to marshal.
 		// e.g, if local time is 2010-10-10T10:10:10 UTC+8
 		// we will change this to 2010-10-10T10:10:10 UTC and then marshal.
@@ -154,7 +157,14 @@ func (t Time) Marshal() ([]byte, error) {
 		err = errors.Errorf("invalid time type %d", t.Type)
 	}
 
-	return b, err
+	if err != nil {
+		return nil, errors.Trace(err)
+	}
+
+	// append fsp to the end
+	b = append(b, byte(t.Fsp))
+
+	return b, nil
 }
 
 // Unmarshal decodes the binary data into Time with current local time.
@@ -165,6 +175,20 @@ func (t *Time) Unmarshal(b []byte) error {
 // UnmarshalInLocation decodes the binary data
 // into Time with a specific time Location.
 func (t *Time) UnmarshalInLocation(b []byte, loc *time.Location) error {
+	if len(b) < 1 {
+		return errors.Errorf("insufficient bytes to unmarshal time")
+	}
+
+	// Get fsp
+	fsp, err := checkFsp(int(int8(b[len(b)-1])))
+	if err != nil {
+		return errors.Trace(err)
+	}
+
+	t.Fsp = fsp
+
+	b = b[:len(b)-1]
+
 	if err := t.Time.UnmarshalBinary(b); err != nil {
 		return errors.Trace(err)
 	}
@@ -175,7 +199,8 @@ func (t *Time) UnmarshalInLocation(b []byte, loc *time.Location) error {
 
 	if t.Type == TypeDatetime || t.Type == TypeDate {
 		// e.g, for 2010-10-10T10:10:10 UTC, we will unmarshal to 2010-10-10T10:10:10 location
-		_, offset := time.Now().In(loc).Zone()
+		_, offset := t.Time.In(loc).Zone()
+
 		t.Time = t.Time.Add(-time.Duration(offset) * time.Second).In(loc)
 		if t.Type == TypeDate {
 			// for date type ,we will only use year, month and day.

mysqldef/time_test.go

@@ -337,6 +337,27 @@ func (s *testTimeSuite) TestCodec(c *C) {
 	err = t4.Unmarshal(b)
 	c.Assert(err, IsNil)
 	c.Assert(t.String(), Equals, t4.String())
+
+	tbl := []string{
+		"2000-01-01 00:00:00.000000",
+		"2000-01-01 00:00:00.123456",
+		"0001-01-01 00:00:00.123456",
+		"2000-06-01 00:00:00.999999",
+	}
+
+	for _, test := range tbl {
+		t, err := ParseTime(test, TypeDatetime, MaxFsp)
+		c.Assert(err, IsNil)
+
+		b, err := t.Marshal()
+		c.Assert(err, IsNil)
+
+		var dest Time
+		dest.Type = TypeDatetime
+		err = dest.Unmarshal(b)
+		c.Assert(err, IsNil)
+		c.Assert(dest.String(), Equals, test)
+	}
 }
 
 func (s *testTimeSuite) TestParseTimeFromNum(c *C) {