Merge pull request #650 from niccokunzmann/remove-pytz

Remove pytz dependency

.github/workflows/tests.yml

@@ -18,6 +18,7 @@ jobs:
         config:
         # [Python version, tox env]
         - ["3.8",   "py38"]
+        - ["3.8",   "nopytz"]
         - ["3.9",   "py39"]
         - ["3.10",  "py310"]
         - ["pypy-3.9", "pypy3"]

CHANGES.rst

@@ -47,9 +47,14 @@ Breaking changes:
 - Remove untested and broken ``LocalTimezone`` and ``FixedOffset`` tzinfo
   sub-classes, see `Issue 67 <https://github.com/collective/icalendar/issues/67>`_
 
+- Remove ``pytz`` as a dependency of ``icalendar``. If you require ``pytz``,
+  add it to your dependency list or install it additionally with::
+
+      pip install icalendar>=6.0.0 pytz
+
 New features:
 
-- ...
+- Add function ``icalendar.use_pytz()``.
 
 Bug fixes:
 

setup.py

@@ -20,7 +20,6 @@
 tests_require = []
 install_requires = [
     'python-dateutil',
-    'pytz',
     # install requirements depending on python version
     # see https://www.python.org/dev/peps/pep-0508/#environment-markers
     'backports.zoneinfo; python_version < "3.9"',

src/icalendar/tests/conftest.py

@@ -4,7 +4,11 @@
     import zoneinfo
 import pytest
 import icalendar
-import pytz
+try:
+    import pytz
+except ImportError:
+    pytz = None
+from datetime import datetime
 from dateutil import tz
 from icalendar.cal import Component, Calendar
 from icalendar.timezone import tzp as _tzp
@@ -13,6 +17,21 @@
 import itertools
 import sys
 
+HAS_PYTZ = pytz is not None
+if HAS_PYTZ:
+    PYTZ_UTC = [
+        pytz.utc,
+        pytz.timezone('UTC'),
+    ]
+    PYTZ_IN_TIMEZONE = [
+        lambda dt, tzname: pytz.timezone(tzname).localize(dt),
+    ]
+    PYTZ_TZP = ["pytz"]
+else:
+    PYTZ_UTC = []
+    PYTZ_IN_TIMEZONE = []
+    PYTZ_TZP = []
+
 
 class DataSource:
     '''A collection of parsed ICS elements (e.g calendars, timezones, events)'''
@@ -76,17 +95,14 @@ def timezones(tzp):
 def events(tzp):
     return DataSource(EVENTS_FOLDER, icalendar.Event.from_ical)
 
-@pytest.fixture(params=[
-    pytz.utc,
+@pytest.fixture(params=PYTZ_UTC + [
     zoneinfo.ZoneInfo('UTC'),
-    pytz.timezone('UTC'),
     tz.UTC,
     tz.gettz('UTC')])
 def utc(request, tzp):
     return request.param
 
-@pytest.fixture(params=[
-    lambda dt, tzname: pytz.timezone(tzname).localize(dt),
+@pytest.fixture(params=PYTZ_IN_TIMEZONE + [
     lambda dt, tzname: dt.replace(tzinfo=tz.gettz(tzname)),
     lambda dt, tzname: dt.replace(tzinfo=zoneinfo.ZoneInfo(tzname))
 ])
@@ -193,7 +209,7 @@ def tzp(tzp_name):
     _tzp.use_default()
 
 
-@pytest.fixture(params=["pytz", "zoneinfo"])
+@pytest.fixture(params=PYTZ_TZP + ["zoneinfo"])
 def other_tzp(request, tzp):
     """This is annother timezone provider.
 
@@ -207,15 +223,13 @@ def other_tzp(request, tzp):
 @pytest.fixture()
 def pytz_only(tzp):
     """Skip tests that are not running under pytz."""
-    if not tzp.uses_pytz():
-        pytest.skip("Not using pytz. Skipping this test.")
+    assert tzp.uses_pytz()
 
 
 @pytest.fixture()
-def zoneinfo_only(tzp):
-    """Skip tests that are not running under pytz."""
-    if not tzp.uses_zoneinfo():
-        pytest.skip("Not using zoneinfo. Skipping this test.")
+def zoneinfo_only(tzp, request, tzp_name):
+    """Skip tests that are not running under zoneinfo."""
+    assert tzp.uses_zoneinfo()
 
 
 def pytest_generate_tests(metafunc):
@@ -228,12 +242,12 @@ def pytest_generate_tests(metafunc):
     See https://docs.pytest.org/en/6.2.x/example/parametrize.html#deferring-the-setup-of-parametrized-resources
     """
     if "tzp_name" in metafunc.fixturenames:
-        tzp_names = ["pytz", "zoneinfo"]
+        tzp_names = PYTZ_TZP + ["zoneinfo"]
         if "zoneinfo_only" in metafunc.fixturenames:
-            tzp_names.remove("pytz")
-        if "pytz_only" in  metafunc.fixturenames:
-            tzp_names.remove("zoneinfo")
-        assert tzp_names, "Use pytz_only or zoneinfo_only but not both!"
+            tzp_names = ["zoneinfo"]
+        if "pytz_only" in metafunc.fixturenames:
+            tzp_names = PYTZ_TZP
+        assert not ("zoneinfo_only" in metafunc.fixturenames and "pytz_only" in metafunc.fixturenames), "Use pytz_only or zoneinfo_only but not both!"
         metafunc.parametrize("tzp_name", tzp_names, scope="module")
 
 
@@ -243,18 +257,26 @@ def __repr__(self):
         return f"ZoneInfo(key={repr(self.key)})"
 
 
-def test_print(obj):
+def doctest_print(obj):
     """doctest print"""
     if isinstance(obj, bytes):
         obj = obj.decode("UTF-8")
     print(str(obj).strip().replace("\r\n", "\n").replace("\r", "\n"))
 
 
+def doctest_import(name, *args, **kw):
+    """Replace the import mechanism to skip the whole doctest if we import pytz."""
+    if name == "pytz":
+        return pytz
+    return __import__(name, *args, **kw)
+
 @pytest.fixture()
 def env_for_doctest(monkeypatch):
     """Modify the environment to make doctests run."""
     monkeypatch.setitem(sys.modules, "zoneinfo", zoneinfo)
     monkeypatch.setattr(zoneinfo, "ZoneInfo", DoctestZoneInfo)
     from icalendar.timezone.zoneinfo import ZONEINFO
     monkeypatch.setattr(ZONEINFO, "utc", zoneinfo.ZoneInfo("UTC"))
-    return {"print": test_print}
+    return {
+        "print": doctest_print
+    }

src/icalendar/tests/prop/test_identity_and_equality.py

@@ -2,22 +2,26 @@
 from icalendar import vDDDTypes
 from datetime import datetime, date, time
 from icalendar.timezone.zoneinfo import zoneinfo
-import pytz
+try:
+    import pytz
+except ImportError:
+    pytz = None
 from dateutil import tz
 import pytest
 from copy import deepcopy
 
 
 
 vDDDTypes_list = [
-    vDDDTypes(pytz.timezone('EST').localize(datetime(year=2022, month=7, day=22, hour=12, minute=7))),
     vDDDTypes(datetime(year=2022, month=7, day=22, hour=12, minute=7, tzinfo=zoneinfo.ZoneInfo("Europe/London"))),
     vDDDTypes(datetime(year=2022, month=7, day=22, hour=12, minute=7)),
     vDDDTypes(datetime(year=2022, month=7, day=22, hour=12, minute=7, tzinfo=tz.UTC)),
     vDDDTypes(date(year=2022, month=7, day=22)),
     vDDDTypes(date(year=2022, month=7, day=23)),
     vDDDTypes(time(hour=22, minute=7, second=2))
 ]
+if pytz:
+    vDDDTypes_list.append(vDDDTypes(pytz.timezone('EST').localize(datetime(year=2022, month=7, day=22, hour=12, minute=7))),)
 
 def identity(x):
     return x

src/icalendar/tests/test_equality.py

@@ -1,6 +1,9 @@
 """Test the equality and inequality of components."""
 import copy
-import pytz
+try:
+    import pytz
+except ImportError:
+    pytz = None
 from icalendar.prop import *
 from datetime import datetime, date, timedelta
 import pytest

src/icalendar/tests/test_pytz_zoneinfo_integration.py

@@ -2,19 +2,31 @@
 
 These are mostly located in icalendar.timezone.
 """
-import pytz
+try:
+    import pytz
+    from icalendar.timezone.pytz import PYTZ
+except ImportError:
+    pytz = None
 from icalendar.timezone.zoneinfo import zoneinfo, ZONEINFO
 from dateutil.tz.tz import _tzicalvtz
-from icalendar.timezone.pytz import PYTZ
 import pytest
 import copy
 import pickle
 from dateutil.rrule import rrule, MONTHLY
 from datetime import datetime
 
+if pytz:
+    PYTZ_TIMEZONES = pytz.all_timezones
+    TZP_ = [PYTZ(), ZONEINFO()]
+    NEW_TZP_NAME = ["pytz", "zoneinfo"]
+else:
+    PYTZ_TIMEZONES = []
+    TZP_ = [ZONEINFO()]
+    NEW_TZP_NAME = ["zoneinfo"]
 
-@pytest.mark.parametrize("tz_name", pytz.all_timezones + list(zoneinfo.available_timezones()))
-@pytest.mark.parametrize("tzp_", [PYTZ(), ZONEINFO()])
+
+@pytest.mark.parametrize("tz_name", PYTZ_TIMEZONES + list(zoneinfo.available_timezones()))
+@pytest.mark.parametrize("tzp_", TZP_)
 def test_timezone_names_are_known(tz_name, tzp_):
     """Make sure that all timezones are understood."""
     if tz_name in ("Factory", "localtime"):
@@ -55,7 +67,7 @@ def test_cache_reuse_timezone_cache(tzp, timezones):
     assert tzp1 is tzp.timezone("custom_Pacific/Fiji"), "Cache is not replaced."
 
 
-@pytest.mark.parametrize("new_tzp_name", ["pytz", "zoneinfo"])
+@pytest.mark.parametrize("new_tzp_name", NEW_TZP_NAME)
 def test_cache_is_emptied_when_tzp_is_switched(tzp, timezones, new_tzp_name):
     """Make sure we do not reuse the timezones created when we switch the provider."""
     tzp.cache_timezone_component(timezones.pacific_fiji)

src/icalendar/tests/test_with_doctest.py

@@ -14,6 +14,8 @@
 import os
 import pytest
 import importlib
+import sys
+import re
 
 HERE = os.path.dirname(__file__) or "."
 ICALENDAR_PATH = os.path.dirname(HERE)
@@ -35,7 +37,12 @@ def test_this_module_is_among_them():
 @pytest.mark.parametrize("module_name", MODULE_NAMES)
 def test_docstring_of_python_file(module_name):
     """This test runs doctest on the Python module."""
-    module = importlib.import_module(module_name)
+    try:
+        module = importlib.import_module(module_name)
+    except ModuleNotFoundError as e:
+        if e.name == "pytz":
+            pytest.skip("pytz is not installed, skipping this module.")
+        raise
     test_result = doctest.testmod(module, name=module_name)
     assert test_result.failed == 0, f"{test_result.failed} errors in {module_name}"
 
@@ -62,14 +69,22 @@ def test_files_is_included(filename):
 
 
 @pytest.mark.parametrize("document", DOCUMENT_PATHS)
-def test_documentation_file(document, zoneinfo_only, env_for_doctest):
+def test_documentation_file(document, zoneinfo_only, env_for_doctest, tzp):
     """This test runs doctest on a documentation file.
 
     functions are also replaced to work.
     """
-    test_result = doctest.testfile(document, module_relative=False, globs=env_for_doctest)
+    try:
+        test_result = doctest.testfile(document, module_relative=False, globs=env_for_doctest, raise_on_error=True)
+    except doctest.UnexpectedException as e:
+        ty, err, tb = e.exc_info
+        if issubclass(ty, ModuleNotFoundError) and err.name == "pytz":
+            pytest.skip("pytz not installed, skipping this file.")
+    finally:
+        tzp.use_zoneinfo()
     assert test_result.failed == 0, f"{test_result.failed} errors in {os.path.basename(document)}"
 
 
 def test_can_import_zoneinfo(env_for_doctest):
     """Allow importing zoneinfo for tests."""
+    assert "zoneinfo" in sys.modules

src/icalendar/timezone/tzp.py

@@ -8,7 +8,7 @@
 from dateutil.rrule import rrule
 
 
-DEFAULT_TIMEZONE_PROVIDER = "pytz"
+DEFAULT_TIMEZONE_PROVIDER = "zoneinfo"
 
 
 class TZP:

tox.ini

@@ -1,6 +1,6 @@
 # to run for a specific environment, use ``tox -e ENVNAME``
 [tox]
-envlist = py38,py39,py310,py311,312,pypy3,docs
+envlist = py38,py39,py310,py311,312,pypy3,docs,nopytz
 # Note: the 'docs' env creates a 'build' directory which may interfere in strange ways
 # with the other environments.  You might see this when you run the tests in parallel.
 # See https://github.com/collective/icalendar/pull/359#issuecomment-1214150269
@@ -11,11 +11,30 @@ deps =
     pytest
     coverage
     hypothesis
+    pytz
 commands =
     coverage run --source=src/icalendar --omit=*/tests/hypothesis/* --omit=*/tests/fuzzed/* --module pytest []
     coverage report
     coverage html
 
+[testenv:nopytz]
+# install with dependencies
+usedevelop = False
+# use lowest version
+basepython = python3.8
+allowlist_externals =
+    rm
+deps =
+    setuptools>=70.1.0
+    pytest
+    coverage
+    hypothesis
+commands =
+    rm -rf build # do not mess up import
+    coverage run --source=src/icalendar --omit=*/tests/hypothesis/* --omit=*/tests/fuzzed/* --module pytest []
+    coverage report
+    coverage html
+
 [testenv:docs]
 deps =
     -r {toxinidir}/requirements_docs.txt