From: Jeff Dairiki <dairiki@dairiki.org>
Subject: [PATCH] Remove dependency on pytz (#1110)
Origin: upstream, https://github.com/lektor/lektor/commit/3ddb731d6f6e97611df6f4a1f3126a79b1399a5b
Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1084286
Forwarded: not-needed

This is a backport of an upstream patch that drops dependency on pytz.

Index: lektor/lektor/types/primitives.py
===================================================================
--- lektor.orig/lektor/types/primitives.py
+++ lektor/lektor/types/primitives.py
@@ -1,9 +1,9 @@
+import re
 from datetime import date
 from datetime import datetime
 
 from babel.dates import get_timezone
 from markupsafe import Markup
-from pytz import FixedOffset
 
 from lektor.constants import PRIMARY_ALT
 from lektor.i18n import get_i18n_block
@@ -117,25 +117,61 @@ class DateTimeType(SingleInputType):
     def value_from_raw(self, raw):
         if raw.value is None:
             return raw.missing_value("Missing datetime")
+
+        # The previous version of this code allowed a timezone name, followed by a zone
+        # offset. In that case the zone name would be ignored (unless the combined zone
+        # name, including the offset, matched an IANA zone key). For the sake of
+        # backwards compatibility we do the same here.
+        m = re.match(
+            r"""
+            (?P<datetime>
+                \d{4} - \d\d? - \d\d?  # YY-MM-DD
+                \s+ \d\d? : \d\d (?P<seconds> :\d\d )? # HH:MM[:SS]
+            )
+            (?: \s+
+                (?P<timezone>
+                    # Long timezone keys, and — on Windows — names containing
+                    # certain characters (those that are not allowed in filenames)
+                    # give zoneinfo gas.
+                    # https://github.com/python/cpython/issues/96463
+                    [^<>:"|?*\x00-\x1f]{,100}?
+                    (?P<zoneoffset> [-+] \d\d (?: :? \d\d ){1,2} )?  # ±HHMM[SS]
+                )
+            )?
+            \Z""",
+            raw.value.strip(),
+            re.DOTALL | re.VERBOSE,
+        )
+        if m is None:
+            return raw.bad_value("Bad datetime format")
+        timezone, zoneoffset = m.group("timezone", "zoneoffset")
+        tz = None
+        if timezone is not None:
+            try:
+                tz = get_timezone(timezone)
+                zoneoffset = None
+            except LookupError:
+                if zoneoffset is None:
+                    return raw.bad_value(f"Unknown timezone {timezone!r}")
+
+        dt = m["datetime"]
+        fmt = "%Y-%m-%d %H:%M"
+        if m["seconds"] is not None:
+            fmt += ":%S"
+        if zoneoffset is not None:
+            dt += f" {zoneoffset}"
+            fmt += " %z"
         try:
-            chunks = raw.value.split(" ")
-            date_info = [int(bit) for bit in chunks[0].split("-")]
-            time_info = [int(bit) for bit in chunks[1].split(":")]
-            datetime_info = date_info + time_info
-            result = datetime(*datetime_info)
-
-            if len(chunks) > 2:
-                try:
-                    tz = get_timezone(chunks[-1])
-                except LookupError:
-                    if len(chunks[-1]) > 5:
-                        chunks[-1] = chunks[-1][-5:]
-                    delta = int(chunks[-1][1:3]) * 60 + int(chunks[-1][3:])
-                    if chunks[-1][0] == "-":
-                        delta *= -1
-                    tz = FixedOffset(delta)
-                return tz.localize(result)
+            result = datetime.strptime(dt, fmt)
+        except ValueError:
+            return raw.bad_value("Invalid datetime")
 
+        if tz is None:
             return result
-        except Exception:
-            return raw.bad_value("Bad date format")
+
+        # as of babel 2.12, get_timezone can return either a pytz timezone
+        # or a zoneinfo timezone
+        assert result.tzinfo is None
+        if hasattr(tz, "localize"):  # pytz
+            return tz.localize(result)
+        return result.replace(tzinfo=tz)
Index: lektor/tests/test_types.py
===================================================================
--- lektor.orig/tests/test_types.py
+++ lektor/tests/test_types.py
@@ -1,6 +1,6 @@
 import datetime
 
-from babel.dates import get_timezone
+import pytest
 from markupsafe import escape
 from markupsafe import Markup
 
@@ -192,161 +192,89 @@ def test_boolean(env, pad):
             assert rv is False
 
 
-def test_datetime(env, pad):
-    field = make_field(env, "datetime")
+dt = datetime.datetime
+
 
+@pytest.mark.parametrize(
+    "value, expected",
+    [
+        ("2016-04-30 01:02:03", dt(2016, 4, 30, 1, 2, 3)),
+        ("1970-1-1 12:34", dt(1970, 1, 1, 12, 34)),
+        ("1970-01-02 12:34", dt(1970, 1, 2, 12, 34)),
+        ("2020-02-03 01:02:03", dt(2020, 2, 3, 1, 2, 3)),
+    ],
+)
+def test_datetime_no_timezone(env, pad, value, expected):
+    field = make_field(env, "datetime")
     with Context(pad=pad):
-        # default
-        rv = field.deserialize_value("2016-04-30 01:02:03", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo is None
+        rv = field.deserialize_value(value, pad=pad)
 
-        # It is not datetime, it is None
-        rv = field.deserialize_value(None, pad=pad)
-        assert isinstance(rv, Undefined)
+    assert rv.replace(tzinfo=None) == expected
+    assert rv.tzinfo is None
 
-        # It is not datetime, it is empty string
-        rv = field.deserialize_value("", pad=pad)
-        assert isinstance(rv, BadValue)
 
-        # It is not datetime, it is date
-        rv = field.deserialize_value("2016-04-30", pad=pad)
-        assert isinstance(rv, BadValue)
+def utc(*args):
+    return datetime.datetime(*args, tzinfo=datetime.timezone.utc)
 
 
-def test_datetime_timezone_utc(env, pad):
-    field = make_field(env, "datetime")
-    with Context(pad=pad):
+@pytest.mark.parametrize(
+    "value, expected",
+    [
         # Known timezone name, UTC
-        rv = field.deserialize_value("2016-04-30 01:02:03 UTC", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo is get_timezone("UTC")
-
-
-def test_datetime_timezone_est(env, pad):
-    field = make_field(env, "datetime")
-    with Context(pad=pad):
+        ("2016-04-30 01:02:03 UTC", utc(2016, 4, 30, 1, 2, 3)),
         # Known timezone name, EST
-        rv = field.deserialize_value("2016-04-30 01:02:03 EST", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo is get_timezone("EST")
-
-
-def test_datetime_timezone_location(env, pad):
-    field = make_field(env, "datetime")
-    with Context(pad=pad):
+        ("2016-04-30 01:02:03 EST", utc(2016, 4, 30, 6, 2, 3)),
         # Known location name, Asia/Seoul
-        rv = field.deserialize_value("2016-04-30 01:02:03 Asia/Seoul", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        tzinfos = get_timezone("Asia/Seoul")._tzinfos  # pylint: disable=no-member
-        assert rv.tzinfo in tzinfos.values()
-
-
-def test_datetime_timezone_kst(env, pad):
-    field = make_field(env, "datetime")
-    with Context(pad=pad):
+        ("2016-04-30 01:02:03 Asia/Seoul", utc(2016, 4, 29, 16, 2, 3)),
         # KST - http://www.timeanddate.com/time/zones/kst
-        rv = field.deserialize_value("2016-04-30 01:02:03 +0900", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo._offset == datetime.timedelta(0, 9 * 60 * 60)
-
-
-def test_datetime_timezone_acst(env, pad):
-    field = make_field(env, "datetime")
-    with Context(pad=pad):
+        ("2016-04-30 01:02:03 +0900", utc(2016, 4, 29, 16, 2, 3)),
         # ACST - http://www.timeanddate.com/time/zones/acst
-        rv = field.deserialize_value("2016-04-30 01:02:03 +0930", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo._offset == datetime.timedelta(0, (9 * 60 + 30) * 60)
-
-
-def test_datetime_timezone_mst(env, pad):
+        ("2016-04-30 01:02:03 +0930", utc(2016, 4, 29, 15, 32, 3)),
+        # MST - http://www.timeanddate.com/time/zones/mst
+        ("2016-04-30 01:02:03 -0700", utc(2016, 4, 30, 8, 2, 3)),
+        # MART - http://www.timeanddate.com/time/zones/mart
+        ("2016-04-30 01:02:03 -0930", utc(2016, 4, 30, 10, 32, 3)),
+        # with (ignored) timezone name (case 1)
+        ("2016-04-30 01:02:03 KST +0900", utc(2016, 4, 29, 16, 2, 3)),
+        # with (ignored) timezone name (case 2)
+        ("2016-04-30 01:02:03 KST+0900", utc(2016, 4, 29, 16, 2, 3)),
+    ],
+)
+def test_datetime_timezone(env, pad, value, expected):
     field = make_field(env, "datetime")
     with Context(pad=pad):
-        # MST - http://www.timeanddate.com/time/zones/mst
-        rv = field.deserialize_value("2016-04-30 01:02:03 -0700", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo._offset == datetime.timedelta(0, -7 * 60 * 60)
+        rv = field.deserialize_value(value, pad=pad)
+    assert rv.astimezone(expected.tzinfo) == expected
 
 
-def test_datetime_timezone_mart(env, pad):
+@pytest.mark.parametrize(
+    "value",
+    [
+        "",
+        "197",
+        "1970",
+        "1970-01",
+        "1970-01-01",
+        "1970-01-01 12",
+        "1970-01-01 12.23",
+        "1970-01 01:02:03",
+        "1970-01-01 12:34 *0800",
+        "1970-01-01 12:34 -081",
+        "1970-01-01 12:34 a\\b",
+        "1970-01-01 12:34 very/unknown/timezone",
+        "1970-01-01 12:34 very/long/timezone" + "e" * 1024,
+    ],
+)
+def test_datetime_invalid(env, pad, value):
     field = make_field(env, "datetime")
     with Context(pad=pad):
-        # MART - http://www.timeanddate.com/time/zones/mart
-        rv = field.deserialize_value("2016-04-30 01:02:03 -0930", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo._offset == datetime.timedelta(0, -(9 * 60 + 30) * 60)
+        rv = field.deserialize_value(value, pad=pad)
+    assert isinstance(rv, BadValue)
 
 
-def test_datetime_timezone_name(env, pad):
+def test_datetime_missing(env, pad):
     field = make_field(env, "datetime")
     with Context(pad=pad):
-        # with timezone name (case 1)
-        rv = field.deserialize_value("2016-04-30 01:02:03 KST +0900", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo._offset == datetime.timedelta(0, 9 * 60 * 60)
-
-        # with timezone name (case 2)
-        rv = field.deserialize_value("2016-04-30 01:02:03 KST+0900", pad=pad)
-        assert isinstance(rv, datetime.datetime)
-        assert rv.year == 2016
-        assert rv.month == 4
-        assert rv.day == 30
-        assert rv.hour == 1
-        assert rv.minute == 2
-        assert rv.second == 3
-        assert rv.tzinfo._offset == datetime.timedelta(0, 9 * 60 * 60)
+        rv = field.deserialize_value(None, pad=pad)
+    assert isinstance(rv, Undefined)
+    assert "Missing value" in rv._undefined_hint
Index: lektor/setup.cfg
===================================================================
--- lektor.orig/setup.cfg
+++ lektor/setup.cfg
@@ -47,8 +47,9 @@ install_requires =
     markupsafe
     mistune0>=0.7.0,<2
     pip>=21.1
+    pytz; python_version<"3.9"  # favor zoneinfo for python>=3.9
     python-slugify
-    pytz
+    tzdata; python_version>="3.9" and sys_platform == 'win32'
     requests
     setuptools>=45.2
     watchdog