Use time.Parse for parsing incoming server times

Following a pprof profiling, using fmt.Scanf was slow. time.Parse is
faster and more readable.

1 files changed, 5 insertions, 8 deletions

diff --git a/irc/tokens.go b/irc/tokens.go
index 7bcde99..ed63535 100644
--- a/irc/tokens.go
+++ b/irc/tokens.go
@@ -366,17 +366,14 @@ func (msg *Message) ParseParams(out ...*string) error {
 	return nil
 }
 
-func parseTimestamp(timestamp string) (time.Time, bool) {
-	var year, month, day, hour, minute, second, millis int
-
-	timestamp = strings.TrimSuffix(timestamp, "Z")
+const serverTimeLayout = "2006-01-02T15:04:05.000Z"
 
-	_, err := fmt.Sscanf(timestamp, "%4d-%2d-%2dT%2d:%2d:%2d.%3d", &year, &month, &day, &hour, &minute, &second, &millis)
-	if err != nil || month < 1 || 12 < month {
+func parseTimestamp(timestamp string) (time.Time, bool) {
+	t, err := time.Parse(serverTimeLayout, timestamp)
+	if err != nil {
 		return time.Time{}, false
 	}
-
-	return time.Date(year, time.Month(month), day, hour, minute, second, millis*1e6, time.UTC), true
+	return t.UTC(), true
 }
 
 // Time returns the time when the message has been sent, if present.