Remove pytz from tools

Author: markcampanelli

pvlib/iotools/pvgis.py

@@ -17,10 +17,12 @@
 import io
 import json
 from pathlib import Path
+from zoneinfo import ZoneInfo
+
 import requests
 import numpy as np
 import pandas as pd
-import pytz
+
 from pvlib.iotools import read_epw, parse_epw
 
 URL = 'https://re.jrc.ec.europa.eu/api/'
@@ -398,10 +400,10 @@ def _coerce_and_roll_tmy(tmy_data, tz, year):
     re-interpreted as zero / UTC.
     """
     if tz:
-        tzname = pytz.timezone(f'Etc/GMT{-tz:+d}')
+        tzname = ZoneInfo(f'Etc/GMT{-tz:+d}')
     else:
         tz = 0
-        tzname = pytz.timezone('UTC')
+        tzname = ZoneInfo('UTC')
     new_index = pd.DatetimeIndex([
         timestamp.replace(year=year, tzinfo=tzname)
         for timestamp in tmy_data.index],

pvlib/location.py

@@ -4,14 +4,16 @@
 
 # Will Holmgren, University of Arizona, 2014-2016.
 
-import pathlib
 import datetime
+import pathlib
+from zoneinfo import ZoneInfo
 
+import h5py
 import pandas as pd
 import pytz
-import h5py
 
-from pvlib import solarposition, clearsky, atmosphere, irradiance
+from pvlib import atmosphere, clearsky, irradiance, solarposition
+from pvlib._deprecation import warn_deprecated
 from pvlib.tools import _degrees_to_index
 
 
@@ -21,10 +23,12 @@ class Location:
     timezone, and altitude data associated with a particular
     geographic location. You can also assign a name to a location object.
 
-    Location objects have two timezone attributes:
+    Location objects have one timezone attribute:
+
+        * ``tz`` is a IANA-compatible standard-library zoneinfo.ZoneInfo.
 
-        * ``tz`` is a IANA timezone string.
-        * ``pytz`` is a pytz timezone object.
+    Thus, the passed timezone must be representable by one of the values in
+    zoneinfo.available_timezones().
 
     Location objects support the print method.
 
@@ -38,12 +42,12 @@ class Location:
         Positive is east of the prime meridian.
         Use decimal degrees notation.
 
-    tz : str, int, float, or pytz.timezone, default 'UTC'.
-        See
-        http://en.wikipedia.org/wiki/List_of_tz_database_time_zones
-        for a list of valid time zones.
-        pytz.timezone objects will be converted to strings.
-        ints and floats must be in hours from UTC.
+    tz : str, int, float, zoneinfo.ZoneInfo, datetime.timezone, or pytz timezone (deprecated), default 'UTC'.
+        See http://en.wikipedia.org/wiki/List_of_tz_database_time_zones for a
+        list of valid time zone strings, or use the function
+        zoneinfo.available_timezones().
+        ints and floats must be in hours N from UTC, and are converted to the
+        Etc/GMT+N or Etc/GMT-N format depending on the sign of N.
 
     altitude : float, optional
         Altitude from sea level in meters.
@@ -59,33 +63,43 @@ class Location:
     pvlib.pvsystem.PVSystem
     """
 
-    def __init__(self, latitude, longitude, tz='UTC', altitude=None,
-                 name=None):
+    def __init__(
+        self, latitude, longitude, tz='UTC', altitude=None, name=None
+    ):
+
+        if name is None:
+            name = ""
+
+        self.name = name
 
         self.latitude = latitude
         self.longitude = longitude
 
-        if isinstance(tz, str):
-            self.tz = tz
-            self.pytz = pytz.timezone(tz)
-        elif isinstance(tz, datetime.timezone):
-            self.tz = 'UTC'
-            self.pytz = pytz.UTC
-        elif isinstance(tz, datetime.tzinfo):
-            self.tz = tz.zone
-            self.pytz = tz
-        elif isinstance(tz, (int, float)):
-            self.tz = tz
-            self.pytz = pytz.FixedOffset(tz*60)
-        else:
-            raise TypeError('Invalid tz specification')
-
         if altitude is None:
             altitude = lookup_altitude(latitude, longitude)
 
         self.altitude = altitude
 
-        self.name = name
+        if isinstance(tz, str):
+            self.tz = ZoneInfo(tz)
+        elif isinstance(tz, int):
+            self.tz = ZoneInfo(f"Etc/GMT{-tz:+d}")
+        elif isinstance(tz, float):
+            self.tz = ZoneInfo(f"Etc/GMT{int(-tz):+d}")
+        elif isinstance(tz, ZoneInfo):
+            self.tz = tz
+        elif isinstance(tz, datetime.timezone):
+            self.tz = ZoneInfo(str(tz))
+        elif isinstance(tz, pytz.BaseTzInfo):
+            warn_deprecated(
+                "0.11.3",
+                message='pytz timezones are deprecated',
+                alternative='use zoneinfo.ZoneInfo from the standard library',
+                obj_type='function argument type',
+            )
+            self.tz = ZoneInfo(tz.zone)
+        else:
+            raise TypeError(f'Invalid tz specification: {tz}')
 
     def __repr__(self):
         attrs = ['name', 'latitude', 'longitude', 'altitude', 'tz']

pvlib/temperature.py

@@ -6,7 +6,6 @@
 import numpy as np
 import pandas as pd
 from pvlib.tools import sind
-from pvlib._deprecation import warn_deprecated
 from pvlib.tools import _get_sample_intervals
 import scipy
 import scipy.constants

pvlib/tests/iotools/test_midc.py

@@ -1,6 +1,5 @@
 import pandas as pd
 import pytest
-import pytz
 
 from pvlib.iotools import midc
 from ..conftest import DATA_DIR, RERUNS, RERUNS_DELAY
@@ -43,7 +42,7 @@ def test_midc__format_index_tz_conversion():
     data = pd.read_csv(MIDC_TESTFILE)
     data = data.rename(columns={'MST': 'PST'})
     data = midc._format_index(data)
-    assert data.index[0].tz == pytz.timezone('Etc/GMT+8')
+    assert str(data.index[0].tz) == 'Etc/GMT+8'
 
 
 def test_midc__format_index_raw():

pvlib/tests/test_clearsky.py

@@ -1,9 +1,9 @@
 from collections import OrderedDict
+from zoneinfo import ZoneInfo
 
 import numpy as np
 from numpy import nan
 import pandas as pd
-import pytz
 from scipy.linalg import hankel
 
 import pytest
@@ -758,7 +758,7 @@ def test_bird():
     times = pd.date_range(start='1/1/2015 0:00', end='12/31/2015 23:00',
                           freq='h')
     tz = -7  # test timezone
-    gmt_tz = pytz.timezone('Etc/GMT%+d' % -(tz))
+    gmt_tz = ZoneInfo(f"Etc/GMT{-tz:+}")
     times = times.tz_localize(gmt_tz)  # set timezone
     times_utc = times.tz_convert('UTC')
     # match test data from BIRD_08_16_2012.xls

pvlib/tests/test_location.py

@@ -1,15 +1,14 @@
 import datetime
 from unittest.mock import ANY
+from zoneinfo import ZoneInfo, ZoneInfoNotFoundError
 
 import numpy as np
 from numpy import nan
 import pandas as pd
 from .conftest import assert_frame_equal, assert_index_equal
 
 import pytest
-
 import pytz
-from pytz.exceptions import UnknownTimeZoneError
 
 import pvlib
 from pvlib import location
@@ -28,15 +27,15 @@ def test_location_all():
 
 
 @pytest.mark.parametrize('tz', [
-    pytz.timezone('US/Arizona'), 'America/Phoenix',  -7, -7.0,
-    datetime.timezone.utc
+    pytz.timezone('US/Arizona'), ZoneInfo('US/Arizona'), 'America/Phoenix',
+    -7, -7.0, datetime.timezone.utc
 ])
 def test_location_tz(tz):
     Location(32.2, -111, tz)
 
 
 def test_location_invalid_tz():
-    with pytest.raises(UnknownTimeZoneError):
+    with pytest.raises(ZoneInfoNotFoundError):
         Location(32.2, -111, 'invalid')
 
 
@@ -58,8 +57,8 @@ def test_location_print_all():
     assert tus.__str__() == expected_str
 
 
-def test_location_print_pytz():
-    tus = Location(32.2, -111, pytz.timezone('US/Arizona'), 700, 'Tucson')
+def test_location_print_zoneinfo():
+    tus = Location(32.2, -111, ZoneInfo('US/Arizona'), 700, 'Tucson')
     expected_str = '\n'.join([
         'Location: ',
         '  name: Tucson',
@@ -215,7 +214,7 @@ def test_from_tmy_3():
     from pvlib.iotools import read_tmy3
     data, meta = read_tmy3(TMY3_TESTFILE, map_variables=True)
     loc = Location.from_tmy(meta, data)
-    assert loc.name is not None
+    assert loc.name != ""
     assert loc.altitude != 0
     assert loc.tz != 'UTC'
     assert_frame_equal(loc.weather, data)
@@ -226,7 +225,7 @@ def test_from_tmy_2():
     from pvlib.iotools import read_tmy2
     data, meta = read_tmy2(TMY2_TESTFILE)
     loc = Location.from_tmy(meta, data)
-    assert loc.name is not None
+    assert loc.name != ""
     assert loc.altitude != 0
     assert loc.tz != 'UTC'
     assert_frame_equal(loc.weather, data)
@@ -237,7 +236,7 @@ def test_from_epw():
     from pvlib.iotools import read_epw
     data, meta = read_epw(epw_testfile)
     loc = Location.from_epw(meta, data)
-    assert loc.name is not None
+    assert loc.name != ""
     assert loc.altitude != 0
     assert loc.tz != 'UTC'
     assert_frame_equal(loc.weather, data)

pvlib/tests/test_solarposition.py

@@ -344,15 +344,13 @@ def test_pyephem_physical_dst(expected_solpos, golden):
 
 @requires_ephem
 def test_calc_time():
-    import pytz
     import math
     # validation from USNO solar position calculator online
 
     epoch = datetime.datetime(1970, 1, 1)
     epoch_dt = pytz.utc.localize(epoch)
 
     loc = tus
-    loc.pressure = 0
     actual_time = pytz.timezone(loc.tz).localize(
         datetime.datetime(2014, 10, 10, 8, 30))
     lb = pytz.timezone(loc.tz).localize(datetime.datetime(2014, 10, 10, tol))

pvlib/tests/test_tools.py

@@ -298,9 +298,7 @@ def test_localize_to_utc(input, expected):
         ),
         (
             {
-                "time": datetime(
-                    1974, 6, 22, 23, 30, 15, tzinfo=ZoneInfo("UTC")
-                )
+                "time": datetime(1974, 6, 22, 23, 30, 15)
             },
             27201.47934027778,
         ),

pvlib/tools.py

@@ -3,10 +3,11 @@
 """
 
 import datetime as dt
+import warnings
+import zoneinfo
+
 import numpy as np
 import pandas as pd
-import pytz
-import warnings
 
 
 def cosd(angle):
@@ -133,13 +134,14 @@ def localize_to_utc(time, location):
     """
     if isinstance(time, dt.datetime):
         if time.tzinfo is None:
-            time = pytz.timezone(location.tz).localize(time)
-        time_utc = time.astimezone(pytz.utc)
+            time = time.replace(tzinfo=location.tz)
+
+        time_utc = time.astimezone(zoneinfo.ZoneInfo("UTC"))
     else:
         try:
             time_utc = time.tz_convert('UTC')
         except TypeError:
-            time_utc = time.tz_localize(location.tz).tz_convert('UTC')
+            time_utc = time.tz_localize(str(location.tz)).tz_convert('UTC')
 
     return time_utc
 
@@ -160,11 +162,11 @@ def datetime_to_djd(time):
     """
 
     if time.tzinfo is None:
-        time_utc = pytz.utc.localize(time)
+        time_utc = time.replace(tzinfo=zoneinfo.ZoneInfo("UTC"))
     else:
-        time_utc = time.astimezone(pytz.utc)
+        time_utc = time.astimezone(zoneinfo.ZoneInfo("UTC"))
 
-    djd_start = pytz.utc.localize(dt.datetime(1899, 12, 31, 12))
+    djd_start = dt.datetime(1899, 12, 31, 12, tzinfo=zoneinfo.ZoneInfo("UTC"))
     djd = (time_utc - djd_start).total_seconds() * 1.0/(60 * 60 * 24)
 
     return djd
@@ -187,10 +189,10 @@ def djd_to_datetime(djd, tz='UTC'):
        The resultant datetime localized to tz
     """
 
-    djd_start = pytz.utc.localize(dt.datetime(1899, 12, 31, 12))
-
+    djd_start = dt.datetime(1899, 12, 31, 12, tzinfo=zoneinfo.ZoneInfo("UTC"))
     utc_time = djd_start + dt.timedelta(days=djd)
-    return utc_time.astimezone(pytz.timezone(tz))
+
+    return utc_time.astimezone(zoneinfo.ZoneInfo(tz))
 
 
 def _pandas_to_doy(pd_object):