Fix SetTimestamp in the correct location (#50)

* Add Test SetUnix

* SetTimestamp in the correct location

carbon.go

@@ -738,8 +738,7 @@ func (c *Carbon) SetWeekendDays(wds []time.Weekday) {
 
 // SetTimestamp sets the current time given a timestamp
 func (c *Carbon) SetTimestamp(sec int64) {
-	t := time.Unix(sec, 0)
-	c.Time = time.Date(t.Year(), t.Month(), t.Day(), t.Hour(), t.Minute(), t.Second(), t.Nanosecond(), c.Location())
+	c.Time = time.Unix(sec, 0).In(c.Location())
 }
 
 // SetTimeZone sets the location from a string

carbon_test.go

@@ -5,6 +5,7 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestAddYearsPositive(t *testing.T) {
@@ -2592,8 +2593,8 @@ func TestCreateFromTimestampUTC(t *testing.T) {
 func TestCreateFromTimestamp(t *testing.T) {
 	c, _ := CreateFromTimestamp(1171502725, "Africa/Cairo")
 
-	expected, _ := Create(2007, time.February, 15, 1, 25, 25, 0, "Africa/Cairo")
-	assert.Equal(t, expected, c, "The date should be 07-02-15 01:25:25")
+	expected, _ := Create(2007, time.February, 15, 3, 25, 25, 0, "Africa/Cairo")
+	assert.Equal(t, expected, c, "The date should be 07-02-15 03:25:25")
 }
 
 func TestCreateFromTime(t *testing.T) {
@@ -2745,3 +2746,11 @@ func TestIsLastMonthFalse(t *testing.T) {
 	assert.Nil(t, err)
 	assert.False(t, c.IsLastMonth())
 }
+
+func TestSetUnix(t *testing.T) {
+	unix := time.Now().UTC().Unix()
+	utcTime, err := CreateFromTimestampUTC(unix)
+
+	require.Nil(t, err)
+	assert.Equal(t, unix, utcTime.Unix())
+}