fix(parser): Fix error handling when dealing with empty layout or format

Author: kuafuRace

parser.go

@@ -133,7 +133,7 @@ func ParseByLayouts(value string, layouts []string, timezone ...string) Carbon {
 		return Carbon{isEmpty: true}
 	}
 	if len(layouts) == 0 {
-		return Parse(value, timezone...)
+		return Carbon{Error: ErrEmptyLayout()}
 	}
 	var (
 		tz  string
@@ -169,7 +169,7 @@ func ParseByFormats(value string, formats []string, timezone ...string) Carbon {
 		return Carbon{isEmpty: true}
 	}
 	if len(formats) == 0 {
-		return Parse(value, timezone...)
+		return Carbon{Error: ErrEmptyFormat()}
 	}
 	var (
 		tz  string

parser_test.go

@@ -156,8 +156,8 @@ func TestParseByLayouts(t *testing.T) {
 	})
 
 	t.Run("empty layouts", func(t *testing.T) {
-		assert.Equal(t, "2020-08-05 13:14:15 +0000 UTC", ParseByLayouts("2020-08-05 13:14:15", []string{}).ToString())
-		assert.Equal(t, "2006-01-02 15:04:05", ParseByLayouts("2020-08-05 13:14:15", []string{}).CurrentLayout())
+		assert.Empty(t, ParseByLayouts("2020-08-05 13:14:15", []string{}).ToString())
+		assert.Empty(t, ParseByLayouts("2020-08-05 13:14:15", []string{}).CurrentLayout())
 	})
 
 	t.Run("invalid timezone", func(t *testing.T) {
@@ -273,8 +273,8 @@ func TestParseByFormats(t *testing.T) {
 	})
 
 	t.Run("empty layouts", func(t *testing.T) {
-		assert.Equal(t, "2020-08-05 13:14:15 +0000 UTC", ParseByFormats("2020-08-05 13:14:15", []string{}).ToString())
-		assert.Equal(t, "2006-01-02 15:04:05", ParseByFormats("2020-08-05 13:14:15", []string{}).CurrentLayout())
+		assert.Empty(t, ParseByFormats("2020-08-05 13:14:15", []string{}).ToString())
+		assert.Empty(t, ParseByFormats("2020-08-05 13:14:15", []string{}).CurrentLayout())
 	})
 
 	t.Run("invalid timezone", func(t *testing.T) {
@@ -444,8 +444,8 @@ func TestParseWithLayouts(t *testing.T) {
 	})
 
 	t.Run("empty layouts", func(t *testing.T) {
-		assert.Equal(t, "2020-08-05 13:14:15 +0000 UTC", ParseWithLayouts("2020-08-05 13:14:15", []string{}).ToString())
-		assert.Equal(t, "2006-01-02 15:04:05", ParseWithLayouts("2020-08-05 13:14:15", []string{}).CurrentLayout())
+		assert.Empty(t, ParseWithLayouts("2020-08-05 13:14:15", []string{}).ToString())
+		assert.Empty(t, ParseWithLayouts("2020-08-05 13:14:15", []string{}).CurrentLayout())
 	})
 
 	t.Run("invalid timezone", func(t *testing.T) {
@@ -483,8 +483,8 @@ func TestParseWithFormats(t *testing.T) {
 	})
 
 	t.Run("empty layouts", func(t *testing.T) {
-		assert.Equal(t, "2020-08-05 13:14:15 +0000 UTC", ParseWithFormats("2020-08-05 13:14:15", []string{}).ToString())
-		assert.Equal(t, "2006-01-02 15:04:05", ParseWithFormats("2020-08-05 13:14:15", []string{}).CurrentLayout())
+		assert.Empty(t, ParseWithFormats("2020-08-05 13:14:15", []string{}).ToString())
+		assert.Empty(t, ParseWithFormats("2020-08-05 13:14:15", []string{}).CurrentLayout())
 	})
 
 	t.Run("invalid timezone", func(t *testing.T) {