gtime: some code style refactoring (#17369)

pkg/components/gtime/gtime.go

@@ -6,23 +6,26 @@ import (
 	"time"
 )
 
-// ParseInterval parses and interval with support for all units that Grafana uses.
+var dateUnitPattern = regexp.MustCompile(`(\d+)([wdy])`)
+
+// ParseInterval parses an interval with support for all units that Grafana uses.
 func ParseInterval(interval string) (time.Duration, error) {
-	re := regexp.MustCompile(`(\d+)([wdy])`)
-	result := re.FindSubmatch([]byte(interval))
+	result := dateUnitPattern.FindSubmatch([]byte(interval))
+
+	if len(result) != 3 {
+		return time.ParseDuration(interval)
+	}
 
-	if len(result) == 3 {
 	num, _ := strconv.Atoi(string(result[1]))
 	period := string(result[2])
 
 	if period == `d` {
 		return time.Hour * 24 * time.Duration(num), nil
-		} else if period == `w` {
-			return time.Hour * 24 * 7 * time.Duration(num), nil
-		} else {
-			return time.Hour * 24 * 7 * 365 * time.Duration(num), nil
 	}
-	} else {
-		return time.ParseDuration(interval)
+
+	if period == `w` {
+		return time.Hour * 24 * 7 * time.Duration(num), nil
 	}
+
+	return time.Hour * 24 * 7 * 365 * time.Duration(num), nil
 }

pkg/components/gtime/gtime_test.go

@@ -15,7 +15,9 @@ func TestParseInterval(t *testing.T) {
 	}{
 		{interval: "1d", duration: time.Hour * 24},
 		{interval: "1w", duration: time.Hour * 24 * 7},
+		{interval: "2w", duration: time.Hour * 24 * 7 * 2},
 		{interval: "1y", duration: time.Hour * 24 * 7 * 365},
+		{interval: "5y", duration: time.Hour * 24 * 7 * 365 * 5},
 		{interval: "1M", err: errors.New("time: unknown unit M in duration 1M")},
 		{interval: "invalid-duration", err: errors.New("time: invalid duration invalid-duration")},
 	}