Removed tzname because it's broken

 * No mapping between TimeInfo.tzname and TimeInfo.timezone
 * tzname of time.h is not well-defined, may have almost arbitrary
   length, and localization may differ
 * Code used hardcoded "UTC" string

2 files changed, 14 insertions, 44 deletions

diff --git a/lib/pure/times.nim b/lib/pure/times.nim
index ab0741d9c..242118f67 100644
--- a/lib/pure/times.nim
+++ b/lib/pure/times.nim
@@ -66,12 +66,6 @@ when defined(posix) and not defined(JS):
 
   when not defined(freebsd) and not defined(netbsd) and not defined(openbsd):
     var timezone {.importc, header: "<time.h>".}: int
-  var
-    tzname {.importc, header: "<time.h>" .}: array[0..1, cstring]
-  # we also need tzset() to make sure that tzname is initialized
-  proc tzset() {.importc, header: "<time.h>".}
-  # calling tzset() implicitly to initialize tzname data.
-  tzset()
 
 elif defined(windows):
   import winlean
@@ -82,12 +76,10 @@ elif defined(windows):
     # visual c's c runtime exposes these under a different name
     var
       timezone {.importc: "_timezone", header: "<time.h>".}: int
-      tzname {.importc: "_tzname", header: "<time.h>"}: array[0..1, cstring]
   else:
     type TimeImpl {.importc: "time_t", header: "<time.h>".} = int
     var
       timezone {.importc, header: "<time.h>".}: int
-      tzname {.importc, header: "<time.h>" .}: array[0..1, cstring]
 
   type
     Time* = distinct TimeImpl
@@ -154,7 +146,6 @@ type
                               ## Always 0 if the target is JS.
     isDST*: bool              ## Determines whether DST is in effect. Always
                               ## ``False`` if time is UTC.
-    tzname*: string           ## The timezone this time is in. E.g. GMT
     timezone*: int            ## The offset of the (non-DST) timezone in seconds
                               ## west of UTC.
 
@@ -237,12 +228,6 @@ proc `==`*(a, b: Time): bool {.
   ## returns true if ``a == b``, that is if both times represent the same value
   result = a - b == 0
 
-when not defined(JS):
-  proc getTzname*(): tuple[nonDST, DST: string] {.tags: [TimeEffect], raises: [],
-    benign.}
-    ## returns the local timezone; ``nonDST`` is the name of the local non-DST
-    ## timezone, ``DST`` is the name of the local DST timezone.
-
 proc getTimezone*(): int {.tags: [TimeEffect], raises: [], benign.}
   ## returns the offset of the local (non-DST) timezone in seconds west of UTC.
 
@@ -371,7 +356,7 @@ proc `+`*(a: TimeInfo, interval: TimeInterval): TimeInfo =
   ## very accurate.
   let t = toSeconds(toTime(a))
   let secs = toSeconds(a, interval)
-  if a.tzname == "UTC":
+  if a.timezone == 0:
     result = getGMTime(fromSeconds(t + secs))
   else:
     result = getLocalTime(fromSeconds(t + secs))
@@ -391,7 +376,7 @@ proc `-`*(a: TimeInfo, interval: TimeInterval): TimeInfo =
   intval.months = - interval.months
   intval.years = - interval.years
   let secs = toSeconds(a, intval)
-  if a.tzname == "UTC":
+  if a.timezone == 0:
     result = getGMTime(fromSeconds(t + secs))
   else:
     result = getLocalTime(fromSeconds(t + secs))
@@ -491,13 +476,6 @@ when not defined(JS):
       weekday: weekDays[int(tm.weekday)],
       yearday: int(tm.yearday),
       isDST: tm.isdst > 0,
-      tzname: if local:
-          if tm.isdst > 0:
-            getTzname().DST
-          else:
-            getTzname().nonDST
-        else:
-          "UTC",
       timezone: if local: getTimezone() else: 0
     )
 
@@ -597,9 +575,6 @@ when not defined(JS):
     ## converts a Windows time to a UNIX `Time` (``time_t``)
     result = Time((t - epochDiff) div rateDiff)
 
-  proc getTzname(): tuple[nonDST, DST: string] =
-    return ($tzname[0], $tzname[1])
-
   proc getTimezone(): int =
     when defined(freebsd) or defined(netbsd) or defined(openbsd):
       var a = timec(nil)
@@ -892,8 +867,6 @@ proc formatToken(info: TimeInfo, token: string, buf: var string) =
     if hrs.abs < 10:
       var atIndex = buf.len-(($hrs & ":00").len-(if hrs < 0: 1 else: 0))
       buf.insert("0", atIndex)
-  of "ZZZ":
-    buf.add(info.tzname)
   of "":
     discard
   else:
@@ -1154,9 +1127,6 @@ proc parseToken(info: var TimeInfo; token, value: string; j: var int) =
     j += 4
     info.timezone += factor * value[j..j+1].parseInt() * 60
     j += 2
-  of "ZZZ":
-    info.tzname = value[j..j+2].toUpperAscii()
-    j += 3
   else:
     # Ignore the token and move forward in the value string by the same length
     j += token.len
diff --git a/tests/stdlib/ttime.nim b/tests/stdlib/ttime.nim
index 065009535..569d465cc 100644
--- a/tests/stdlib/ttime.nim
+++ b/tests/stdlib/ttime.nim
@@ -10,26 +10,26 @@ import
 # Tue 19 Jan 03:14:07 GMT 2038
 
 var t = getGMTime(fromSeconds(2147483647))
-doAssert t.format("ddd dd MMM hh:mm:ss ZZZ yyyy") == "Tue 19 Jan 03:14:07 UTC 2038"
-doAssert t.format("ddd ddMMMhh:mm:ssZZZyyyy") == "Tue 19Jan03:14:07UTC2038"
+doAssert t.format("ddd dd MMM hh:mm:ss yyyy") == "Tue 19 Jan 03:14:07 2038"
+doAssert t.format("ddd ddMMMhh:mm:ssyyyy") == "Tue 19Jan03:14:072038"
 
 doAssert t.format("d dd ddd dddd h hh H HH m mm M MM MMM MMMM s" &
-  " ss t tt y yy yyy yyyy yyyyy z zz zzz ZZZ") ==
-  "19 19 Tue Tuesday 3 03 3 03 14 14 1 01 Jan January 7 07 A AM 8 38 038 2038 02038 0 00 00:00 UTC"
+  " ss t tt y yy yyy yyyy yyyyy z zz zzz") ==
+  "19 19 Tue Tuesday 3 03 3 03 14 14 1 01 Jan January 7 07 A AM 8 38 038 2038 02038 0 00 00:00"
 
 doAssert t.format("yyyyMMddhhmmss") == "20380119031407"
 
 var t2 = getGMTime(fromSeconds(160070789)) # Mon 27 Jan 16:06:29 GMT 1975
 doAssert t2.format("d dd ddd dddd h hh H HH m mm M MM MMM MMMM s" &
-  " ss t tt y yy yyy yyyy yyyyy z zz zzz ZZZ") ==
-  "27 27 Mon Monday 4 04 16 16 6 06 1 01 Jan January 29 29 P PM 5 75 975 1975 01975 0 00 00:00 UTC"
+  " ss t tt y yy yyy yyyy yyyyy z zz zzz") ==
+  "27 27 Mon Monday 4 04 16 16 6 06 1 01 Jan January 29 29 P PM 5 75 975 1975 01975 0 00 00:00"
 
 when not defined(JS):
   when sizeof(Time) == 8:
     var t3 = getGMTime(fromSeconds(889067643645)) # Fri  7 Jun 19:20:45 BST 30143
     doAssert t3.format("d dd ddd dddd h hh H HH m mm M MM MMM MMMM s" &
-      " ss t tt y yy yyy yyyy yyyyy z zz zzz ZZZ") ==
-      "7 07 Fri Friday 6 06 18 18 20 20 6 06 Jun June 45 45 P PM 3 43 143 0143 30143 0 00 00:00 UTC"
+      " ss t tt y yy yyy yyyy yyyyy z zz zzz") ==
+      "7 07 Fri Friday 6 06 18 18 20 20 6 06 Jun June 45 45 P PM 3 43 143 0143 30143 0 00 00:00"
     doAssert t3.format(":,[]()-/") == ":,[]()-/"
 
 var t4 = getGMTime(fromSeconds(876124714)) # Mon  6 Oct 08:58:34 BST 1997
@@ -52,22 +52,22 @@ parseTest("Tuesday at 09:04am on Dec 15, 2015",
 parseTest("Thu Jan 12 15:04:05 2006", "ddd MMM dd HH:mm:ss yyyy",
     "Thu Jan 12 15:04:05 2006", 11)
 # UnixDate    = "Mon Jan _2 15:04:05 MST 2006"
-parseTest("Thu Jan 12 15:04:05 MST 2006", "ddd MMM dd HH:mm:ss ZZZ yyyy",
+parseTest("Thu Jan 12 15:04:05 2006", "ddd MMM dd HH:mm:ss yyyy",
     "Thu Jan 12 15:04:05 2006", 11)
 # RubyDate    = "Mon Jan 02 15:04:05 -0700 2006"
 parseTest("Mon Feb 29 15:04:05 -07:00 2016", "ddd MMM dd HH:mm:ss zzz yyyy",
     "Mon Feb 29 15:04:05 2016", 59) # leap day
 # RFC822      = "02 Jan 06 15:04 MST"
-parseTest("12 Jan 16 15:04 MST", "dd MMM yy HH:mm ZZZ",
+parseTest("12 Jan 16 15:04", "dd MMM yy HH:mm",
     "Tue Jan 12 15:04:00 2016", 11)
 # RFC822Z     = "02 Jan 06 15:04 -0700" # RFC822 with numeric zone
 parseTest("01 Mar 16 15:04 -07:00", "dd MMM yy HH:mm zzz",
     "Tue Mar  1 15:04:00 2016", 60) # day after february in leap year
 # RFC850      = "Monday, 02-Jan-06 15:04:05 MST"
-parseTest("Monday, 12-Jan-06 15:04:05 MST", "dddd, dd-MMM-yy HH:mm:ss ZZZ",
+parseTest("Monday, 12-Jan-06 15:04:05", "dddd, dd-MMM-yy HH:mm:ss",
     "Thu Jan 12 15:04:05 2006", 11)
 # RFC1123     = "Mon, 02 Jan 2006 15:04:05 MST"
-parseTest("Sun, 01 Mar 2015 15:04:05 MST", "ddd, dd MMM yyyy HH:mm:ss ZZZ",
+parseTest("Sun, 01 Mar 2015 15:04:05", "ddd, dd MMM yyyy HH:mm:ss",
     "Sun Mar  1 15:04:05 2015", 59) # day after february in non-leap year
 # RFC1123Z    = "Mon, 02 Jan 2006 15:04:05 -0700" # RFC1123 with numeric zone
 parseTest("Thu, 12 Jan 2006 15:04:05 -07:00", "ddd, dd MMM yyyy HH:mm:ss zzz",