Times: JS: Add yearday to TimeInfo.

Add yearday calculation to getLocalTime and getGMTime, so that yearday is not 0 for TimeInfo instances under JS backend.

Yearday 0 has no sense and contradicts the behaviour under C backend, where yearday is an int from 1 to 365, i.e. cannot be 0 even theoretically.

lib/pure/times.nim

@@ -597,9 +597,12 @@ elif defined(JS):
     result.month = Month(t.getMonth())
     result.year = t.getFullYear()
     result.weekday = weekDays[t.getDay()]
-    result.yearday = 0
     result.timezone = getTimezone()
 
+    result.yearday = result.monthday - 1
+    for month in mJan..<result.month:
+      result.yearday += getDaysInMonth(month, result.year)
+
   proc getGMTime(t: Time): TimeInfo =
     result.second = t.getUTCSeconds()
     result.minute = t.getUTCMinutes()
@@ -608,7 +611,10 @@ elif defined(JS):
     result.month = Month(t.getUTCMonth())
     result.year = t.getUTCFullYear()
     result.weekday = weekDays[t.getUTCDay()]
-    result.yearday = 0
+
+    result.yearday = result.monthday - 1
+    for month in mJan..<result.month:
+      result.yearday += getDaysInMonth(month, result.year)
 
   proc timeInfoToTime(timeInfo: TimeInfo): Time = toTime(timeInfo)