Add tzres DLL parser

4 files changed, 439 insertions, 316 deletions

diff --git a/dateutil/test/test.py b/dateutil/test/test.py
index 7ee8349..c7166cf 100644
--- a/dateutil/test/test.py
+++ b/dateutil/test/test.py
@@ -16,9 +16,6 @@ try:
 except ImportError:
     import unittest
 
-MISSING_TARBALL = ("This test fails if you don't have the dateutil "
-                   "timezone file installed. Please read the README")
-
 from datetime import *
 
 from dateutil.relativedelta import *
@@ -5682,316 +5679,5 @@ class EasterTest(unittest.TestCase):
             self.assertEqual(western,  easter(western.year,  EASTER_WESTERN))
             self.assertEqual(orthodox, easter(orthodox.year, EASTER_ORTHODOX))
 
-class TZTest(unittest.TestCase):
-
-    TZFILE_EST5EDT = b"""
-VFppZgAAAAAAAAAAAAAAAAAAAAAAAAAEAAAABAAAAAAAAADrAAAABAAAABCeph5wn7rrYKCGAHCh
-ms1gomXicKOD6eCkaq5wpTWnYKZTyvCnFYlgqDOs8Kj+peCqE47wqt6H4KvzcPCsvmngrdNS8K6e
-S+CvszTwsH4t4LGcUXCyZ0pgs3wzcLRHLGC1XBVwticOYLc793C4BvBguRvZcLnm0mC7BPXwu8a0
-YLzk1/C9r9DgvsS58L+PsuDApJvwwW+U4MKEffDDT3bgxGRf8MUvWODGTXxwxw864MgtXnDI+Fdg
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-4GJJRfBjXhLgZCkn8GU99OBmEkRwZx3W4GfyJnBo/bjgadIIcGrdmuBrsepwbMa3YG2RzHBupplg
-b3GucHCGe2BxWsrwcmZdYHM6rPB0Rj9gdRqO8HYvW+B2+nDweA894HjaUvB57x/gero08HvPAeB8
-o1Fwfa7j4H6DM3B/jsXgAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
-AAEAAQABAgMBAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
-AAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEA
-AQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
-AAEAAQABAAEAAQABAAEAAQABAAEAAf//x8ABAP//ubAABP//x8ABCP//x8ABDEVEVABFU1QARVdU
-AEVQVAAAAAABAAAAAQ==
-    """
-
-    EUROPE_HELSINKI = b"""
-VFppZgAAAAAAAAAAAAAAAAAAAAAAAAAFAAAABQAAAAAAAAB1AAAABQAAAA2kc28Yy85RYMy/hdAV
-I+uQFhPckBcDzZAX876QGOOvkBnToJAaw5GQG7y9EBysrhAdnJ8QHoyQEB98gRAgbHIQIVxjECJM
-VBAjPEUQJCw2ECUcJxAmDBgQJwVDkCf1NJAo5SWQKdUWkCrFB5ArtPiQLKTpkC2U2pAuhMuQL3S8
-kDBkrZAxXdkQMnK0EDM9uxA0UpYQNR2dEDYyeBA2/X8QOBuUkDjdYRA5+3aQOr1DEDvbWJA8pl+Q
-Pbs6kD6GQZA/mxyQQGYjkEGEORBCRgWQQ2QbEEQl55BFQ/0QRgXJkEcj3xBH7uYQSQPBEEnOyBBK
-46MQS66qEEzMv5BNjowQTqyhkE9ubhBQjIOQUVeKkFJsZZBTN2yQVExHkFUXTpBWLCmQVvcwkFgV
-RhBY1xKQWfUoEFq29JBb1QoQXKAREF207BBef/MQX5TOEGBf1RBhfeqQYj+3EGNdzJBkH5kQZT2u
-kGYItZBnHZCQZ+iXkGj9cpBpyHmQat1UkGuoW5BsxnEQbYg9kG6mUxBvaB+QcIY1EHFRPBByZhcQ
-czEeEHRF+RB1EQAQdi8VkHbw4hB4DveQeNDEEHnu2ZB6sKYQe867kHyZwpB9rp2QfnmkkH+Of5AC
-AQIDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQD
-BAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAME
-AwQAABdoAAAAACowAQQAABwgAAkAACowAQQAABwgAAlITVQARUVTVABFRVQAAAAAAQEAAAABAQ==
-    """
-
-    NEW_YORK = b"""
-VFppZgAAAAAAAAAAAAAAAAAAAAAAAAAEAAAABAAAABcAAADrAAAABAAAABCeph5wn7rrYKCGAHCh
-ms1gomXicKOD6eCkaq5wpTWnYKZTyvCnFYlgqDOs8Kj+peCqE47wqt6H4KvzcPCsvmngrdNS8K6e
-S+CvszTwsH4t4LGcUXCyZ0pgs3wzcLRHLGC1XBVwticOYLc793C4BvBguRvZcLnm0mC7BPXwu8a0
-YLzk1/C9r9DgvsS58L+PsuDApJvwwW+U4MKEffDDT3bgxGRf8MUvWODGTXxwxw864MgtXnDI+Fdg
-yg1AcMrYOWDLiPBw0iP0cNJg++DTdeTw1EDd4NVVxvDWIL/g1zWo8NgAoeDZFYrw2eCD4Nr+p3Db
-wGXg3N6JcN2pgmDevmtw34lkYOCeTXDhaUZg4n4vcONJKGDkXhFw5Vcu4OZHLfDnNxDg6CcP8OkW
-8uDqBvHw6vbU4Ovm0/Ds1rbg7ca18O6/02Dvr9Jw8J+1YPGPtHDyf5dg82+WcPRfeWD1T3hw9j9b
-YPcvWnD4KHfg+Q88cPoIWeD6+Fjw++g74PzYOvD9yB3g/rgc8P+n/+AAl/7wAYfh4AJ34PADcP5g
-BGD9cAVQ4GEGQN9yBzDCYgeNGXMJEKRjCa2U9ArwhmQL4IV1DNmi5Q3AZ3YOuYTmD6mD9xCZZucR
-iWX4EnlI6BNpR/kUWSrpFUkp+RY5DOoXKQv6GCIpaxkI7fsaAgtsGvIKfBvh7Wwc0ex8HcHPbR6x
-zn0fobFtIHYA/SGBk20iVeL+I2qv7iQ1xP4lSpHuJhWm/ycqc+8n/sOAKQpV8CnepYAq6jfxK76H
-gSzTVHItnmmCLrM2cy9+S4MwkxhzMWdoBDJy+nQzR0oENFLcdTUnLAU2Mr51NwcOBjgb2vY45vAG
-Ofu89jrG0gY72572PK/uhj27gPY+j9CGP5ti9kBvsoZBhH92Qk+UhkNkYXZEL3aHRURDd0XzqQdH
-LV/3R9OLB0kNQfdJs20HSu0j90uciYdM1kB3TXxrh062IndPXE2HUJYEd1E8L4dSdeZ3UxwRh1RV
-yHdU+/OHVjWqd1blEAdYHsb3WMTyB1n+qPdapNQHW96K91yEtgddvmz3XmSYB1+eTvdgTbSHYYdr
-d2ItlodjZ013ZA14h2VHL3dl7VqHZycRd2fNPIdpBvN3aa0eh2rm1XdrljsHbM/x9212HQdur9P3
-b1X/B3CPtfdxNeEHcm+X93MVwwd0T3n3dP7fh3Y4lnd23sGHeBh4d3i+o4d5+Fp3ep6Fh3vYPHd8
-fmeHfbged35eSYd/mAB3AAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
-AAEAAQABAgMBAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
-AAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEA
-AQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
-AAEAAQABAAEAAQABAAEAAQABAAEAAf//x8ABAP//ubAABP//x8ABCP//x8ABDEVEVABFU1QARVdU
-AEVQVAAEslgAAAAAAQWk7AEAAAACB4YfggAAAAMJZ1MDAAAABAtIhoQAAAAFDSsLhQAAAAYPDD8G
-AAAABxDtcocAAAAIEs6mCAAAAAkVn8qJAAAACheA/goAAAALGWIxiwAAAAwdJeoMAAAADSHa5Q0A
-AAAOJZ6djgAAAA8nf9EPAAAAECpQ9ZAAAAARLDIpEQAAABIuE1ySAAAAEzDnJBMAAAAUM7hIlAAA
-ABU2jBAVAAAAFkO3G5YAAAAXAAAAAQAAAAE=
-    """
-
-    TZICAL_EST5EDT = """
-BEGIN:VTIMEZONE
-TZID:US-Eastern
-LAST-MODIFIED:19870101T000000Z
-TZURL:http://zones.stds_r_us.net/tz/US-Eastern
-BEGIN:STANDARD
-DTSTART:19671029T020000
-RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
-TZOFFSETFROM:-0400
-TZOFFSETTO:-0500
-TZNAME:EST
-END:STANDARD
-BEGIN:DAYLIGHT
-DTSTART:19870405T020000
-RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
-TZOFFSETFROM:-0500
-TZOFFSETTO:-0400
-TZNAME:EDT
-END:DAYLIGHT
-END:VTIMEZONE
-    """
-
-    def testStrStart1(self):
-        self.assertEqual(datetime(2003, 4, 6, 1, 59,
-                                  tzinfo=tzstr("EST5EDT")).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00,
-                                  tzinfo=tzstr("EST5EDT")).tzname(), "EDT")
-
-    def testStrEnd1(self):
-        self.assertEqual(datetime(2003, 10, 26, 0, 59,
-                                  tzinfo=tzstr("EST5EDT")).tzname(), "EDT")
-        self.assertEqual(datetime(2003, 10, 26, 1, 00,
-                                  tzinfo=tzstr("EST5EDT")).tzname(), "EST")
-
-    def testStrStart2(self):
-        s = "EST5EDT,4,0,6,7200,10,0,26,7200,3600"
-        self.assertEqual(datetime(2003, 4, 6, 1, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-
-    def testStrEnd2(self):
-        s = "EST5EDT,4,0,6,7200,10,0,26,7200,3600"
-        self.assertEqual(datetime(2003, 10, 26, 0, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-        self.assertEqual(datetime(2003, 10, 26, 1, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-
-    def testStrStart3(self):
-        s = "EST5EDT,4,1,0,7200,10,-1,0,7200,3600"
-        self.assertEqual(datetime(2003, 4, 6, 1, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-
-    def testStrEnd3(self):
-        s = "EST5EDT,4,1,0,7200,10,-1,0,7200,3600"
-        self.assertEqual(datetime(2003, 10, 26, 0, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-        self.assertEqual(datetime(2003, 10, 26, 1, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-
-    def testStrStart4(self):
-        s = "EST5EDT4,M4.1.0/02:00:00,M10-5-0/02:00"
-        self.assertEqual(datetime(2003, 4, 6, 1, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-
-    def testStrEnd4(self):
-        s = "EST5EDT4,M4.1.0/02:00:00,M10-5-0/02:00"
-        self.assertEqual(datetime(2003, 10, 26, 0, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-        self.assertEqual(datetime(2003, 10, 26, 1, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-
-    def testStrStart5(self):
-        s = "EST5EDT4,95/02:00:00,298/02:00"
-        self.assertEqual(datetime(2003, 4, 6, 1, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-
-    def testStrEnd5(self):
-        s = "EST5EDT4,95/02:00:00,298/02"
-        self.assertEqual(datetime(2003, 10, 26, 0, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-        self.assertEqual(datetime(2003, 10, 26, 1, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-
-    def testStrStart6(self):
-        s = "EST5EDT4,J96/02:00:00,J299/02:00"
-        self.assertEqual(datetime(2003, 4, 6, 1, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-
-    def testStrEnd6(self):
-        s = "EST5EDT4,J96/02:00:00,J299/02"
-        self.assertEqual(datetime(2003, 10, 26, 0, 59,
-                                  tzinfo=tzstr(s)).tzname(), "EDT")
-        self.assertEqual(datetime(2003, 10, 26, 1, 00,
-                                  tzinfo=tzstr(s)).tzname(), "EST")
-
-    def testStrStr(self):
-        # Test that tzstr() won't throw an error if given a str instead
-        # of a unicode literal.
-        self.assertEqual(datetime(2003, 4, 6, 1, 59,
-                                  tzinfo=tzstr(str("EST5EDT"))).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00,
-                                  tzinfo=tzstr(str("EST5EDT"))).tzname(), "EDT")
-
-    def testStrCmp1(self):
-        self.assertEqual(tzstr("EST5EDT"),
-                         tzstr("EST5EDT4,M4.1.0/02:00:00,M10-5-0/02:00"))
-
-    def testStrCmp2(self):
-        self.assertEqual(tzstr("EST5EDT"),
-                         tzstr("EST5EDT,4,1,0,7200,10,-1,0,7200,3600"))
-
-    def testRangeCmp1(self):
-        self.assertEqual(tzstr("EST5EDT"),
-                         tzrange("EST", -18000, "EDT", -14400,
-                                 relativedelta(hours=+2,
-                                               month=4, day=1,
-                                               weekday=SU(+1)),
-                                 relativedelta(hours=+1,
-                                               month=10, day=31,
-                                               weekday=SU(-1))))
-
-    def testRangeCmp2(self):
-        self.assertEqual(tzstr("EST5EDT"),
-                         tzrange("EST", -18000, "EDT"))
-
-    def testFileStart1(self):
-        tz = tzfile(BytesIO(base64.b64decode(self.TZFILE_EST5EDT)))
-        self.assertEqual(datetime(2003, 4, 6, 1, 59, tzinfo=tz).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00, tzinfo=tz).tzname(), "EDT")
-
-    def testFileEnd1(self):
-        tz = tzfile(BytesIO(base64.b64decode(self.TZFILE_EST5EDT)))
-        self.assertEqual(datetime(2003, 10, 26, 0, 59, tzinfo=tz).tzname(),
-                         "EDT")
-        self.assertEqual(datetime(2003, 10, 26, 1, 00, tzinfo=tz).tzname(),
-                         "EST")
-
-    def testZoneInfoFileStart1(self):
-        tz = zoneinfo.gettz("EST5EDT")
-        self.assertEqual(datetime(2003, 4, 6, 1, 59, tzinfo=tz).tzname(), "EST",
-                         MISSING_TARBALL)
-        self.assertEqual(datetime(2003, 4, 6, 2, 00, tzinfo=tz).tzname(), "EDT")
-
-    def testZoneInfoFileEnd1(self):
-        tz = zoneinfo.gettz("EST5EDT")
-        self.assertEqual(datetime(2003, 10, 26, 0, 59, tzinfo=tz).tzname(),
-                         "EDT", MISSING_TARBALL)
-        self.assertEqual(datetime(2003, 10, 26, 1, 00, tzinfo=tz).tzname(),
-                         "EST")
-
-    def testZoneInfoOffsetSignal(self):
-        utc = zoneinfo.gettz("UTC")
-        nyc = zoneinfo.gettz("America/New_York")
-        self.assertNotEqual(utc, None, MISSING_TARBALL)
-        self.assertNotEqual(nyc, None)
-        t0 = datetime(2007, 11, 4, 0, 30, tzinfo=nyc)
-        t1 = t0.astimezone(utc)
-        t2 = t1.astimezone(nyc)
-        self.assertEqual(t0, t2)
-        self.assertEqual(nyc.dst(t0), timedelta(hours=1))
-
-    def testTzNameNone(self):
-        gmt5 = tzoffset(None, -18000)       # -5:00
-        self.assertIs(datetime(2003, 10, 26, 0, 0, tzinfo=gmt5).tzname(),
-                      None)
-
-
-    def testICalStart1(self):
-        tz = tzical(StringIO(self.TZICAL_EST5EDT)).get()
-        self.assertEqual(datetime(2003, 4, 6, 1, 59, tzinfo=tz).tzname(), "EST")
-        self.assertEqual(datetime(2003, 4, 6, 2, 00, tzinfo=tz).tzname(), "EDT")
-
-    def testICalEnd1(self):
-        tz = tzical(StringIO(self.TZICAL_EST5EDT)).get()
-        self.assertEqual(datetime(2003, 10, 26, 0, 59, tzinfo=tz).tzname(), "EDT")
-        self.assertEqual(datetime(2003, 10, 26, 1, 00, tzinfo=tz).tzname(), "EST")
-
-    def testRoundNonFullMinutes(self):
-        # This timezone has an offset of 5992 seconds in 1900-01-01.
-        tz = tzfile(BytesIO(base64.b64decode(self.EUROPE_HELSINKI)))
-        self.assertEqual(str(datetime(1900, 1, 1, 0, 0, tzinfo=tz)),
-                             "1900-01-01 00:00:00+01:40")
-
-    def testLeapCountDecodesProperly(self):
-        # This timezone has leapcnt, and failed to decode until
-        # Eugene Oden notified about the issue.
-        tz = tzfile(BytesIO(base64.b64decode(self.NEW_YORK)))
-        self.assertEqual(datetime(2007, 3, 31, 20, 12).tzname(), None)
-
-    def testGettz(self):
-        # bug 892569
-        str(gettz('UTC'))
-
-    def testBrokenIsDstHandling(self):
-        # tzrange._isdst() was using a date() rather than a datetime().
-        # Issue reported by Lennart Regebro.
-        dt = datetime(2007, 8, 6, 4, 10, tzinfo=tzutc())
-        self.assertEqual(dt.astimezone(tz=gettz("GMT+2")),
-                          datetime(2007, 8, 6, 6, 10, tzinfo=tzstr("GMT+2")))
-
-    def testGMTHasNoDaylight(self):
-        # tzstr("GMT+2") improperly considered daylight saving time.
-        # Issue reported by Lennart Regebro.
-        dt = datetime(2007, 8, 6, 4, 10)
-        self.assertEqual(gettz("GMT+2").dst(dt), timedelta(0))
-
-    def testGMTOffset(self):
-        # GMT and UTC offsets have inverted signal when compared to the
-        # usual TZ variable handling.
-        dt = datetime(2007, 8, 6, 4, 10, tzinfo=tzutc())
-        self.assertEqual(dt.astimezone(tz=tzstr("GMT+2")),
-                          datetime(2007, 8, 6, 6, 10, tzinfo=tzstr("GMT+2")))
-        self.assertEqual(dt.astimezone(tz=gettz("UTC-2")),
-                          datetime(2007, 8, 6, 2, 10, tzinfo=tzstr("UTC-2")))
-
-    @unittest.skipUnless(sys.platform.startswith("win"), "requires Windows")
-    def testIsdstZoneWithNoDaylightSaving(self):
-        tz = tzwin.tzwin("UTC")
-        dt = parse("2013-03-06 19:08:15")
-        self.assertFalse(tz._isdst(dt))
-
-    @unittest.skipIf(sys.platform.startswith("win"), "requires Unix")
-    def testTZSetDoesntCorrupt(self):
-        # if we start in non-UTC then tzset UTC make sure parse doesn't get
-        # confused
-        os.environ['TZ'] = 'UTC'
-        _time.tzset()
-        # this should parse to UTC timezone not the original timezone
-        dt = parse('2014-07-20T12:34:56+00:00')
-        self.assertEqual(str(dt), '2014-07-20 12:34:56+00:00')
 
 # vim:ts=4:sw=4
diff --git a/dateutil/test/test_tz.py b/dateutil/test/test_tz.py
new file mode 100644
index 0000000..de125c3
--- /dev/null
+++ b/dateutil/test/test_tz.py
@@ -0,0 +1,356 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from datetime import datetime, timedelta
+from six import BytesIO, StringIO
+
+import sys
+import base64
+import unittest
+IS_WIN = sys.platform.startswith('win')
+
+# dateutil imports
+from dateutil.relativedelta import relativedelta
+from dateutil.parser import parse
+from dateutil.tz import *
+from dateutil import zoneinfo
+
+try:
+    from dateutil import tzwin
+except ImportError as e:
+    if IS_WIN:
+        raise e
+    else:
+        pass
+
+MISSING_TARBALL = ("This test fails if you don't have the dateutil "
+                   "timezone file installed. Please read the README")
+
+TZFILE_EST5EDT = b"""
+VFppZgAAAAAAAAAAAAAAAAAAAAAAAAAEAAAABAAAAAAAAADrAAAABAAAABCeph5wn7rrYKCGAHCh
+ms1gomXicKOD6eCkaq5wpTWnYKZTyvCnFYlgqDOs8Kj+peCqE47wqt6H4KvzcPCsvmngrdNS8K6e
+S+CvszTwsH4t4LGcUXCyZ0pgs3wzcLRHLGC1XBVwticOYLc793C4BvBguRvZcLnm0mC7BPXwu8a0
+YLzk1/C9r9DgvsS58L+PsuDApJvwwW+U4MKEffDDT3bgxGRf8MUvWODGTXxwxw864MgtXnDI+Fdg
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+4GJJRfBjXhLgZCkn8GU99OBmEkRwZx3W4GfyJnBo/bjgadIIcGrdmuBrsepwbMa3YG2RzHBupplg
+b3GucHCGe2BxWsrwcmZdYHM6rPB0Rj9gdRqO8HYvW+B2+nDweA894HjaUvB57x/gero08HvPAeB8
+o1Fwfa7j4H6DM3B/jsXgAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
+AAEAAQABAgMBAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
+AAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEA
+AQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
+AAEAAQABAAEAAQABAAEAAQABAAEAAf//x8ABAP//ubAABP//x8ABCP//x8ABDEVEVABFU1QARVdU
+AEVQVAAAAAABAAAAAQ==
+"""
+
+EUROPE_HELSINKI = b"""
+VFppZgAAAAAAAAAAAAAAAAAAAAAAAAAFAAAABQAAAAAAAAB1AAAABQAAAA2kc28Yy85RYMy/hdAV
+I+uQFhPckBcDzZAX876QGOOvkBnToJAaw5GQG7y9EBysrhAdnJ8QHoyQEB98gRAgbHIQIVxjECJM
+VBAjPEUQJCw2ECUcJxAmDBgQJwVDkCf1NJAo5SWQKdUWkCrFB5ArtPiQLKTpkC2U2pAuhMuQL3S8
+kDBkrZAxXdkQMnK0EDM9uxA0UpYQNR2dEDYyeBA2/X8QOBuUkDjdYRA5+3aQOr1DEDvbWJA8pl+Q
+Pbs6kD6GQZA/mxyQQGYjkEGEORBCRgWQQ2QbEEQl55BFQ/0QRgXJkEcj3xBH7uYQSQPBEEnOyBBK
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+kGYItZBnHZCQZ+iXkGj9cpBpyHmQat1UkGuoW5BsxnEQbYg9kG6mUxBvaB+QcIY1EHFRPBByZhcQ
+czEeEHRF+RB1EQAQdi8VkHbw4hB4DveQeNDEEHnu2ZB6sKYQe867kHyZwpB9rp2QfnmkkH+Of5AC
+AQIDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQD
+BAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAMEAwQDBAME
+AwQAABdoAAAAACowAQQAABwgAAkAACowAQQAABwgAAlITVQARUVTVABFRVQAAAAAAQEAAAABAQ==
+"""
+
+NEW_YORK = b"""
+VFppZgAAAAAAAAAAAAAAAAAAAAAAAAAEAAAABAAAABcAAADrAAAABAAAABCeph5wn7rrYKCGAHCh
+ms1gomXicKOD6eCkaq5wpTWnYKZTyvCnFYlgqDOs8Kj+peCqE47wqt6H4KvzcPCsvmngrdNS8K6e
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+zn0fobFtIHYA/SGBk20iVeL+I2qv7iQ1xP4lSpHuJhWm/ycqc+8n/sOAKQpV8CnepYAq6jfxK76H
+gSzTVHItnmmCLrM2cy9+S4MwkxhzMWdoBDJy+nQzR0oENFLcdTUnLAU2Mr51NwcOBjgb2vY45vAG
+Ofu89jrG0gY72572PK/uhj27gPY+j9CGP5ti9kBvsoZBhH92Qk+UhkNkYXZEL3aHRURDd0XzqQdH
+LV/3R9OLB0kNQfdJs20HSu0j90uciYdM1kB3TXxrh062IndPXE2HUJYEd1E8L4dSdeZ3UxwRh1RV
+yHdU+/OHVjWqd1blEAdYHsb3WMTyB1n+qPdapNQHW96K91yEtgddvmz3XmSYB1+eTvdgTbSHYYdr
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+fmeHfbged35eSYd/mAB3AAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
+AAEAAQABAgMBAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
+AAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEA
+AQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQABAAEAAQAB
+AAEAAQABAAEAAQABAAEAAQABAAEAAf//x8ABAP//ubAABP//x8ABCP//x8ABDEVEVABFU1QARVdU
+AEVQVAAEslgAAAAAAQWk7AEAAAACB4YfggAAAAMJZ1MDAAAABAtIhoQAAAAFDSsLhQAAAAYPDD8G
+AAAABxDtcocAAAAIEs6mCAAAAAkVn8qJAAAACheA/goAAAALGWIxiwAAAAwdJeoMAAAADSHa5Q0A
+AAAOJZ6djgAAAA8nf9EPAAAAECpQ9ZAAAAARLDIpEQAAABIuE1ySAAAAEzDnJBMAAAAUM7hIlAAA
+ABU2jBAVAAAAFkO3G5YAAAAXAAAAAQAAAAE=
+"""
+
+TZICAL_EST5EDT = """
+BEGIN:VTIMEZONE
+TZID:US-Eastern
+LAST-MODIFIED:19870101T000000Z
+TZURL:http://zones.stds_r_us.net/tz/US-Eastern
+BEGIN:STANDARD
+DTSTART:19671029T020000
+RRULE:FREQ=YEARLY;BYDAY=-1SU;BYMONTH=10
+TZOFFSETFROM:-0400
+TZOFFSETTO:-0500
+TZNAME:EST
+END:STANDARD
+BEGIN:DAYLIGHT
+DTSTART:19870405T020000
+RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=4
+TZOFFSETFROM:-0500
+TZOFFSETTO:-0400
+TZNAME:EDT
+END:DAYLIGHT
+END:VTIMEZONE
+"""
+
+class TZTest(unittest.TestCase):
+    def testStrStart1(self):
+        self.assertEqual(datetime(2003, 4, 6, 1, 59,
+                                  tzinfo=tzstr("EST5EDT")).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00,
+                                  tzinfo=tzstr("EST5EDT")).tzname(), "EDT")
+
+    def testStrEnd1(self):
+        self.assertEqual(datetime(2003, 10, 26, 0, 59,
+                                  tzinfo=tzstr("EST5EDT")).tzname(), "EDT")
+        self.assertEqual(datetime(2003, 10, 26, 1, 00,
+                                  tzinfo=tzstr("EST5EDT")).tzname(), "EST")
+
+    def testStrStart2(self):
+        s = "EST5EDT,4,0,6,7200,10,0,26,7200,3600"
+        self.assertEqual(datetime(2003, 4, 6, 1, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+
+    def testStrEnd2(self):
+        s = "EST5EDT,4,0,6,7200,10,0,26,7200,3600"
+        self.assertEqual(datetime(2003, 10, 26, 0, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+        self.assertEqual(datetime(2003, 10, 26, 1, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+
+    def testStrStart3(self):
+        s = "EST5EDT,4,1,0,7200,10,-1,0,7200,3600"
+        self.assertEqual(datetime(2003, 4, 6, 1, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+
+    def testStrEnd3(self):
+        s = "EST5EDT,4,1,0,7200,10,-1,0,7200,3600"
+        self.assertEqual(datetime(2003, 10, 26, 0, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+        self.assertEqual(datetime(2003, 10, 26, 1, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+
+    def testStrStart4(self):
+        s = "EST5EDT4,M4.1.0/02:00:00,M10-5-0/02:00"
+        self.assertEqual(datetime(2003, 4, 6, 1, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+
+    def testStrEnd4(self):
+        s = "EST5EDT4,M4.1.0/02:00:00,M10-5-0/02:00"
+        self.assertEqual(datetime(2003, 10, 26, 0, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+        self.assertEqual(datetime(2003, 10, 26, 1, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+
+    def testStrStart5(self):
+        s = "EST5EDT4,95/02:00:00,298/02:00"
+        self.assertEqual(datetime(2003, 4, 6, 1, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+
+    def testStrEnd5(self):
+        s = "EST5EDT4,95/02:00:00,298/02"
+        self.assertEqual(datetime(2003, 10, 26, 0, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+        self.assertEqual(datetime(2003, 10, 26, 1, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+
+    def testStrStart6(self):
+        s = "EST5EDT4,J96/02:00:00,J299/02:00"
+        self.assertEqual(datetime(2003, 4, 6, 1, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+
+    def testStrEnd6(self):
+        s = "EST5EDT4,J96/02:00:00,J299/02"
+        self.assertEqual(datetime(2003, 10, 26, 0, 59,
+                                  tzinfo=tzstr(s)).tzname(), "EDT")
+        self.assertEqual(datetime(2003, 10, 26, 1, 00,
+                                  tzinfo=tzstr(s)).tzname(), "EST")
+
+    def testStrStr(self):
+        # Test that tzstr() won't throw an error if given a str instead
+        # of a unicode literal.
+        self.assertEqual(datetime(2003, 4, 6, 1, 59,
+                                  tzinfo=tzstr(str("EST5EDT"))).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00,
+                                  tzinfo=tzstr(str("EST5EDT"))).tzname(), "EDT")
+
+    def testStrCmp1(self):
+        self.assertEqual(tzstr("EST5EDT"),
+                         tzstr("EST5EDT4,M4.1.0/02:00:00,M10-5-0/02:00"))
+
+    def testStrCmp2(self):
+        self.assertEqual(tzstr("EST5EDT"),
+                         tzstr("EST5EDT,4,1,0,7200,10,-1,0,7200,3600"))
+
+    def testRangeCmp1(self):
+        from dateutil.relativedelta import SU
+        self.assertEqual(tzstr("EST5EDT"),
+                         tzrange("EST", -18000, "EDT", -14400,
+                                 relativedelta(hours=+2,
+                                               month=4, day=1,
+                                               weekday=SU(+1)),
+                                 relativedelta(hours=+1,
+                                               month=10, day=31,
+                                               weekday=SU(-1))))
+
+    def testRangeCmp2(self):
+        self.assertEqual(tzstr("EST5EDT"),
+                         tzrange("EST", -18000, "EDT"))
+
+    def testFileStart1(self):
+        tz = tzfile(BytesIO(base64.b64decode(TZFILE_EST5EDT)))
+        self.assertEqual(datetime(2003, 4, 6, 1, 59, tzinfo=tz).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00, tzinfo=tz).tzname(), "EDT")
+
+    def testFileEnd1(self):
+        tz = tzfile(BytesIO(base64.b64decode(TZFILE_EST5EDT)))
+        self.assertEqual(datetime(2003, 10, 26, 0, 59, tzinfo=tz).tzname(),
+                         "EDT")
+        self.assertEqual(datetime(2003, 10, 26, 1, 00, tzinfo=tz).tzname(),
+                         "EST")
+
+    def testZoneInfoFileStart1(self):
+        tz = zoneinfo.gettz("EST5EDT")
+        self.assertEqual(datetime(2003, 4, 6, 1, 59, tzinfo=tz).tzname(), "EST",
+                         MISSING_TARBALL)
+        self.assertEqual(datetime(2003, 4, 6, 2, 00, tzinfo=tz).tzname(), "EDT")
+
+    def testZoneInfoFileEnd1(self):
+        tz = zoneinfo.gettz("EST5EDT")
+        self.assertEqual(datetime(2003, 10, 26, 0, 59, tzinfo=tz).tzname(),
+                         "EDT", MISSING_TARBALL)
+        self.assertEqual(datetime(2003, 10, 26, 1, 00, tzinfo=tz).tzname(),
+                         "EST")
+
+    def testZoneInfoOffsetSignal(self):
+        utc = zoneinfo.gettz("UTC")
+        nyc = zoneinfo.gettz("America/New_York")
+        self.assertNotEqual(utc, None, MISSING_TARBALL)
+        self.assertNotEqual(nyc, None)
+        t0 = datetime(2007, 11, 4, 0, 30, tzinfo=nyc)
+        t1 = t0.astimezone(utc)
+        t2 = t1.astimezone(nyc)
+        self.assertEqual(t0, t2)
+        self.assertEqual(nyc.dst(t0), timedelta(hours=1))
+
+    def testTzNameNone(self):
+        gmt5 = tzoffset(None, -18000)       # -5:00
+        self.assertIs(datetime(2003, 10, 26, 0, 0, tzinfo=gmt5).tzname(),
+                      None)
+
+
+    def testICalStart1(self):
+        tz = tzical(StringIO(TZICAL_EST5EDT)).get()
+        self.assertEqual(datetime(2003, 4, 6, 1, 59, tzinfo=tz).tzname(), "EST")
+        self.assertEqual(datetime(2003, 4, 6, 2, 00, tzinfo=tz).tzname(), "EDT")
+
+    def testICalEnd1(self):
+        tz = tzical(StringIO(TZICAL_EST5EDT)).get()
+        self.assertEqual(datetime(2003, 10, 26, 0, 59, tzinfo=tz).tzname(), "EDT")
+        self.assertEqual(datetime(2003, 10, 26, 1, 00, tzinfo=tz).tzname(), "EST")
+
+    def testRoundNonFullMinutes(self):
+        # This timezone has an offset of 5992 seconds in 1900-01-01.
+        tz = tzfile(BytesIO(base64.b64decode(EUROPE_HELSINKI)))
+        self.assertEqual(str(datetime(1900, 1, 1, 0, 0, tzinfo=tz)),
+                             "1900-01-01 00:00:00+01:40")
+
+    def testLeapCountDecodesProperly(self):
+        # This timezone has leapcnt, and failed to decode until
+        # Eugene Oden notified about the issue.
+        tz = tzfile(BytesIO(base64.b64decode(NEW_YORK)))
+        self.assertEqual(datetime(2007, 3, 31, 20, 12).tzname(), None)
+
+    def testGettz(self):
+        # bug 892569
+        str(gettz('UTC'))
+
+    def testBrokenIsDstHandling(self):
+        # tzrange._isdst() was using a date() rather than a datetime().
+        # Issue reported by Lennart Regebro.
+        dt = datetime(2007, 8, 6, 4, 10, tzinfo=tzutc())
+        self.assertEqual(dt.astimezone(tz=gettz("GMT+2")),
+                          datetime(2007, 8, 6, 6, 10, tzinfo=tzstr("GMT+2")))
+
+    def testGMTHasNoDaylight(self):
+        # tzstr("GMT+2") improperly considered daylight saving time.
+        # Issue reported by Lennart Regebro.
+        dt = datetime(2007, 8, 6, 4, 10)
+        self.assertEqual(gettz("GMT+2").dst(dt), timedelta(0))
+
+    def testGMTOffset(self):
+        # GMT and UTC offsets have inverted signal when compared to the
+        # usual TZ variable handling.
+        dt = datetime(2007, 8, 6, 4, 10, tzinfo=tzutc())
+        self.assertEqual(dt.astimezone(tz=tzstr("GMT+2")),
+                          datetime(2007, 8, 6, 6, 10, tzinfo=tzstr("GMT+2")))
+        self.assertEqual(dt.astimezone(tz=gettz("UTC-2")),
+                          datetime(2007, 8, 6, 2, 10, tzinfo=tzstr("UTC-2")))
+
+    @unittest.skipIf(IS_WIN, "requires Unix")
+    def testTZSetDoesntCorrupt(self):
+        # if we start in non-UTC then tzset UTC make sure parse doesn't get
+        # confused
+        os.environ['TZ'] = 'UTC'
+        _time.tzset()
+        # this should parse to UTC timezone not the original timezone
+        dt = parse('2014-07-20T12:34:56+00:00')
+        self.assertEqual(str(dt), '2014-07-20 12:34:56+00:00')
+
+@unittest.skipIf(not IS_WIN, "Requires Windows")
+class TzWinTest(unittest.TestCase):
+    def testTzResLoadName(self):
+        # This may not work right on non-US locales.
+        tzr = tzwin.tzres()
+        self.assertEqual(tzr.load_name(112), "Eastern Standard Time")
+
+    def testTzResNameFromString(self):
+        tzr = tzwin.tzres()
+        self.assertEqual(tzr.name_from_string('@tzres.dll,-221'),
+                         'Alaskan Daylight Time')
+
+        self.assertEqual(tzr.name_from_string('Samoa Daylight Time'),
+                         'Samoa Daylight Time')
+
+        with self.assertRaises(ValueError):
+            tzr.name_from_string('@tzres.dll,100')
+
+    def testIsdstZoneWithNoDaylightSaving(self):
+        tz = tzwin.tzwin("UTC")
+        dt = parse("2013-03-06 19:08:15")
+        self.assertFalse(tz._isdst(dt))
\ No newline at end of file
diff --git a/dateutil/tz/win.py b/dateutil/tz/win.py
index 3003f2f..3751a04 100644
--- a/dateutil/tz/win.py
+++ b/dateutil/tz/win.py
@@ -4,9 +4,16 @@ import struct
 
 from six.moves import winreg
 
+try:
+    import ctypes
+    from ctypes import wintypes
+except ValueError:
+    # ValueError is raised on non-Windows systems for some horrible reason.
+    raise ImportError("Running tzwin on non-Windows system")
+
 from .__init__ import tzname_in_python2
 
-__all__ = ["tzwin", "tzwinlocal"]
+__all__ = ["tzwin", "tzwinlocal", "tzres"]
 
 ONEWEEK = datetime.timedelta(7)
 
@@ -28,6 +35,81 @@ def _settzkeyname():
 TZKEYNAME = _settzkeyname()
 
 
+class tzres(object):
+    """
+    Class for accessing `tzres.dll`, which contains timezone name related
+    resources.
+
+    ..versionadded:: 2.5.0
+    """
+    p_wchar = ctypes.POINTER(wintypes.WCHAR)        # Pointer to a wide char
+
+    def __init__(self, tzres_loc='tzres.dll'):
+        # Load the user32 DLL so we can load strings from tzres
+        user32 = ctypes.WinDLL('user32')
+        
+        # Specify the LoadStringW function
+        user32.LoadStringW.argtypes = (wintypes.HINSTANCE,
+                                       wintypes.UINT,
+                                       wintypes.LPWSTR,
+                                       ctypes.c_int)
+
+        self.LoadStringW = user32.LoadStringW
+        self._tzres = ctypes.WinDLL(tzres_loc)
+        self.tzres_loc = tzres_loc
+
+    def load_name(self, offset):
+        """
+        Load a timezone name from a DLL offset (integer).
+        
+        >>> from dateutil.tzwin import tzres
+        >>> tzr = tzres()
+        >>> print(tzr.load_name(112))
+        'Eastern Standard Time'
+
+        :param offset:
+            A positive integer value referring to a string from the tzres dll.
+
+        ..note:
+            Offsets found in the registry are generally of the form
+            `@tzres.dll,-114`. The offset in this case if 114, not -114.
+
+        """
+        resource = self.p_wchar()
+        lpBuffer = ctypes.cast(ctypes.byref(resource), wintypes.LPWSTR)
+        nchar = self.LoadStringW(self._tzres._handle, offset, lpBuffer, 0)
+        return resource[:nchar]
+
+    def name_from_string(self, tzname_str):
+        """
+        Parse strings as returned from the Windows registry into the time zone
+        name as defined in the registry.
+
+        >>> from dateutil.tzwin import tzres
+        >>> tzr = tzres()
+        >>> print(tzr.name_from_string('@tzres.dll,-251'))
+        'Dateline Daylight Time'
+        >>> print(tzr.name_from_string('Eastern Standard Time'))
+        'Eastern Standard Time'
+
+        :param tzname_str:
+            A timezone name string as returned from a Windows registry key.
+
+        :return:
+            Returns the localized timezone string from tzres.dll if the string
+            is of the form `@tzres.dll,-offset`, else returns the input string.
+        """
+        if not tzname_str.startswith('@'):
+            return tzname_str
+
+        name_splt = tzname_str.split(',-')
+        try:
+            offset = int(name_splt[1])
+        except:
+            raise ValueError("Malformed timezone string.")
+
+        return self.load_name(offset)
+
 class tzwinbase(datetime.tzinfo):
     """tzinfo class based on win32's timezones available in the registry."""
 
@@ -126,7 +208,6 @@ class tzwin(tzwinbase):
 class tzwinlocal(tzwinbase):
 
     def __init__(self):
-
         with winreg.ConnectRegistry(None, winreg.HKEY_LOCAL_MACHINE) as handle:
 
             with winreg.OpenKey(handle, TZLOCALKEYNAME) as tzlocalkey:
diff --git a/dateutil/zoneinfo/dateutil-zoneinfo.tar.gz b/dateutil/zoneinfo/dateutil-zoneinfo.tar.gz
deleted file mode 100644
index 6d5c7a5..0000000
--- a/dateutil/zoneinfo/dateutil-zoneinfo.tar.gz
+++ /dev/null