refactor: Refactor time layout parsing logic #296

Author: kuafuRace

parser.go

@@ -54,38 +54,29 @@ func ParseByLayout(value, layout string, timezone ...string) *Carbon {
 	if c.HasError() {
 		return c
 	}
-	if layout == TimestampLayout {
-		ts, err := parseTimestamp(value)
-		if err != nil {
-			c.Error = err
-			return c
-		}
-		return CreateFromTimestamp(ts, c.Timezone())
-	}
-	if layout == TimestampMilliLayout {
-		ts, err := parseTimestamp(value)
-		if err != nil {
-			c.Error = err
-			return c
-		}
-		return CreateFromTimestampMilli(ts, c.Timezone())
-	}
-	if layout == TimestampMicroLayout {
+
+	// timestamp layouts
+	switch layout {
+	case TimestampLayout, TimestampMilliLayout, TimestampMicroLayout, TimestampNanoLayout:
 		ts, err := parseTimestamp(value)
 		if err != nil {
 			c.Error = err
 			return c
 		}
-		return CreateFromTimestampMicro(ts, c.Timezone())
-	}
-	if layout == TimestampNanoLayout {
-		ts, err := parseTimestamp(value)
-		if err != nil {
-			c.Error = err
-			return c
+
+		switch layout {
+		case TimestampLayout:
+			return CreateFromTimestamp(ts, c.Timezone())
+		case TimestampMilliLayout:
+			return CreateFromTimestampMilli(ts, c.Timezone())
+		case TimestampMicroLayout:
+			return CreateFromTimestampMicro(ts, c.Timezone())
+		case TimestampNanoLayout:
+			return CreateFromTimestampNano(ts, c.Timezone())
 		}
-		return CreateFromTimestampNano(ts, c.Timezone())
 	}
+
+	// other layouts
 	tt, err := time.ParseInLocation(layout, value, c.loc)
 	if err != nil {
 		c.Error = fmt.Errorf("%w: %w", ErrMismatchedLayout(value, layout), c.Error)