CHANGELOG.md

@@ -5,17 +5,6 @@ All notable changes to WuttJamaican will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
-## v0.26.0 (2025-12-17)
-
-### Feat
-
-- add "complete" timezone support
-- add `localtime()` function, app method
-
-### Fix
-
-- remove unused import
-
 ## v0.25.0 (2025-12-15)
 
 ### Feat

docs/conf.py

@@ -30,7 +30,6 @@ exclude_patterns = ["_build", "Thumbs.db", ".DS_Store"]
 
 intersphinx_mapping = {
     "alembic": ("https://alembic.sqlalchemy.org/en/latest/", None),
-    "dateutil": ("https://dateutil.readthedocs.io/en/stable/", None),
     "humanize": ("https://humanize.readthedocs.io/en/stable/", None),
     "mako": ("https://docs.makotemplates.org/en/latest/", None),
     "packaging": ("https://packaging.python.org/en/latest/", None),

docs/index.rst

@@ -59,7 +59,6 @@ Contents
    glossary
    narr/install/index
    narr/config/index
-   narr/datetime
    narr/db/index
    narr/cli/index
    narr/email/index

docs/narr/datetime.rst

@@ -1,279 +0,0 @@
-
-===================
- DateTime Behavior
-===================
-
-There must be a way to handle :class:`~python:datetime.datetime` data,
-such that we can keep straight any timezone(s) which may be involved
-for the app.
-
-As a rule, we store datetime values as "naive/UTC" within the
-:term:`app database`, and convert to "aware/local" as needed for
-display to the user etc.
-
-A related rule is that any *naive* datetime is assumed to be UTC.  If
-you have a naive/local value then you should convert it to aware/local
-or else the framework logic will misinterpret it.  (See below,
-:ref:`convert-to-localtime`.)
-
-With these rules in place, the workhorse methods are:
-
-* :meth:`~wuttjamaican.app.AppHandler.localtime()`
-* :meth:`~wuttjamaican.app.AppHandler.make_utc()`
-* :meth:`~wuttjamaican.app.AppHandler.render_datetime()`
-
-
-Time Zone Config/Lookup
------------------------
-
-Technically no config is required; the default timezone can be gleaned
-from the OS::
-
-   # should always return *something* :)
-   tz_default = app.get_timezone()
-
-The default (aka. local) timezone is used by
-:meth:`~wuttjamaican.app.AppHandler.localtime()` and therefore also
-:meth:`~wuttjamaican.app.AppHandler.render_datetime()`.
-
-Config can override the default/local timezone; it's assumed most apps
-will do this.  If desired, other alternate timezone(s) may be
-configured as well:
-
-.. code-block:: ini
-
-   [wutta]
-   timezone.default = America/Chicago
-   timezone.eastcoast = America/New_York
-   timezone.westcoast = America/Los_Angeles
-
-Corresponding :class:`python:datetime.tzinfo` objects can be fetched
-via :meth:`~wuttjamaican.app.AppHandler.get_timezone()`::
-
-   tz_default = app.get_timezone() # => America/Chicago
-
-   tz_eastcoast = app.get_timezone("eastcoast")
-   tz_westcoast = app.get_timezone("westcoast")
-
-
-UTC vs. Local Time
-------------------
-
-Since we store values as naive/UTC, but display to the user as
-aware/local, we often need to convert values between these (and
-related) formats.
-
-
-.. _convert-to-utc:
-
-Convert to UTC
-~~~~~~~~~~~~~~
-
-When a datetime value is written to the app DB, it must be naive/UTC.
-
-Below are 4 examples for converting values to UTC time zone.  In
-short, use :meth:`~wuttjamaican.app.AppHandler.make_utc()` - but if
-providing a naive value, it must already be UTC!  (Because *all* naive
-values are assumed to be UTC.  Provide zone-aware values when
-necessary to avoid confusion.)
-
-These examples assume ``America/Chicago`` (UTC-0600) for the "local"
-timezone, with a local time value of 2:15 PM (so, 8:15 PM UTC)::
-
-   # naive/UTC => naive/UTC
-   # (nb. this conversion is not actually needed of course, but we
-   # show the example to be thorough)
-   # nb. value has no timezone but is already correct (8:15 PM UTC)
-   dt = datetime.datetime(2025, 12, 16, 20, 15)
-   utc = app.make_utc(dt)
-
-   # aware/UTC => naive/UTC
-   # nb. value has expicit timezone, w/ correct time (8:15 PM UTC)
-   dt = datetime.datetime(2025, 12, 16, 20, 15, tzinfo=datetime.timezone.utc)
-   utc = app.make_utc(dt)
-
-   # aware/local => naive/UTC
-   tzlocal = app.get_timezone()
-   # nb. value has expicit timezone, w/ correct time (2:15 PM local)
-   dt = datetime.datetime(2025, 12, 16, 14, 15, tzinfo=tzlocal)
-   utc = app.make_utc(dt)
-
-If your value is naive/local then you can't simply pass it to
-:meth:`~wuttjamaican.app.AppHandler.make_utc()` - since that assumes
-naive values are already UTC.  (Again, *all* naive values are assumed
-to be UTC.)
-
-Instead, first call :meth:`~wuttjamaican.app.AppHandler.localtime()`
-with ``from_utc=False`` to add local time zone awareness::
-
-   # naive/local => naive/UTC
-   # nb. value has no timezone but is correct for local zone (2:15 PM)
-   dt = datetime.datetime(2025, 12, 16, 14, 15)
-   # must first convert, and be sure to specify it's *not* UTC
-   # (in practice this just sets the local timezone)
-   dt = app.localtime(dt, from_utc=False)
-   # value is now "aware/local" so can proceed
-   utc = app.make_utc(dt)
-
-The result of all examples shown above (8:15 PM UTC)::
-
-   >>> utc
-   datetime.datetime(2025, 12, 16, 20, 15)
-
-
-.. _convert-to-localtime:
-
-Convert to Local Time
-~~~~~~~~~~~~~~~~~~~~~
-
-When a datetime value is read from the app DB, it must be converted
-(from naive/UTC) to aware/local for display to user.
-
-Below are 4 examples for converting values to local time zone.  In
-short, use :meth:`~wuttjamaican.app.AppHandler.localtime()` - but if
-providing a naive value, you should specify ``from_utc`` param as
-needed.
-
-These examples assume ``America/Chicago`` (UTC-0600) for the "local"
-timezone, with a local time value of 2:15 PM (so, 8:15 PM UTC)::
-
-   # naive/UTC => aware/local
-   # nb. value has no timezone but is already correct (8:15 PM UTC)
-   dt = datetime.datetime(2025, 12, 16, 20, 15)
-   # nb. can omit from_utc since it is assumed for naive values
-   local = app.localtime(dt)
-   # nb. or, specify it explicitly anyway
-   local = app.localtime(dt, from_utc=True)
-
-   # aware/UTC => aware/local
-   # nb. value has expicit timezone, w/ correct time (8:15 PM UTC)
-   dt = datetime.datetime(2025, 12, 16, 20, 15, tzinfo=datetime.timezone.utc)
-   local = app.localtime(dt)
-
-   # aware/local => aware/local
-   # (nb. this conversion is not actually needed of course, but we
-   # show the example to be thorough)
-   tzlocal = app.get_timezone()
-   # nb. value has expicit timezone, w/ correct time (2:15 PM local)
-   dt = datetime.datetime(2025, 12, 16, 14, 15, tzinfo=tzlocal)
-   # nb. the input and output values are the same here, both aware/local
-   local = app.localtime(dt)
-
-If your value is naive/local then you can't simply pass it to
-:meth:`~wuttjamaican.app.AppHandler.localtime()` with no qualifiers -
-since that assumes naive values are already UTC by default.
-
-Instead specify ``from_utc=False`` to ensure the value is interpreted
-correctly::
-
-   # naive/local => aware/local
-   # nb. value has no timezone but is correct for local zone (2:15 PM)
-   dt = datetime.datetime(2025, 12, 16, 14, 15)
-   # nb. must specify from_utc to avoid misinterpretation
-   local = app.localtime(dt, from_utc=False)
-
-The result of all examples shown above (2:15 PM local)::
-
-   >>> local
-   datetime.datetime(2025, 12, 16, 14, 15, tzinfo=zoneinfo.ZoneInfo("America/Chicago"))
-
-
-Displaying to the User
-----------------------
-
-Whenever a datetime should be displayed to the user, call
-:meth:`~wuttjamaican.app.AppHandler.render_datetime()`.  That will (by
-default) convert the value to aware/local and then render it using a
-common format.
-
-(Once again, this will *not* work for naive/local values.  Those must
-be explicitly converted to aware/local since the framework assumes
-*all* naive values are in UTC.)
-
-You can specify ``local=False`` when calling ``render_datetime()`` to
-avoid its default conversion.
-
-See also :ref:`convert-to-localtime` (above) for examples of how to
-convert any value to aware/local.
-
-.. code-block:: python
-
-   # naive/UTC
-   dt = app.make_utc()
-   print(app.render_datetime(dt))
-
-   # aware/UTC
-   dt = app.make_utc(tzinfo=True)
-   print(app.render_datetime(dt))
-
-   # aware/local
-   dt = app.localtime()
-   print(app.render_datetime(dt))
-
-   # naive/local
-   dt = datetime.datetime.now()
-   # nb. must explicitly convert to aware/local
-   dt = app.localtime(dt, from_utc=False)
-   # nb. can skip redundant conversion via local=False
-   print(app.render_datetime(dt, local=False))
-
-
-Within the Database
--------------------
-
-This section describes storage and access details for datetime values
-within the :term:`app database`.
-
-
-Column Type
-~~~~~~~~~~~
-
-There is not a consistent/simple way to store timezone for datetime
-values in all database backends.  Therefore we must always store the
-values as naive/UTC so app logic can reliably interpret them.  (Hence
-that particular rule.)
-
-All built-in :term:`data models <data model>` use the
-:class:`~sqlalchemy:sqlalchemy.types.DateTime` column type (for
-datetime fields), with its default behavior.  Any app schema
-extensions should (usually) do the same.
-
-
-Writing to the DB
-~~~~~~~~~~~~~~~~~
-
-When a datetime value is written to the app DB, it must be naive/UTC.
-
-See :ref:`convert-to-utc` (above) for examples of how to convert any
-value to naive/UTC.
-
-Apps typically "write" data via the ORM.  Regardless, the key point is
-that you should only pass naive/UTC values into the DB::
-
-   model = app.model
-   session = app.make_session()
-
-   # obtain aware/local value (for example)
-   tz = app.get_timezone()
-   dt = datetime.datetime(2025, 12, 16, 14, 15, tzinfo=tz)
-
-   # convert to naive/UTC when passing to DB
-   sprocket = model.Sprocket()
-   sprocket.some_dt_attr = app.make_utc(dt)
-   sprocket.created = app.make_utc() # "now"
-   session.add(sprocket)
-
-   session.commit()
-
-
-Reading from the DB
-~~~~~~~~~~~~~~~~~~~
-
-Nothing special happens when reading datetime values from the DB; they
-will be naive/UTC just like they were written::
-
-   sprocket = session.get(model.Sprocket, uuid)
-
-   # these will be naive/UTC
-   dt = sprocket.some_dt_attr
-   dt2 = sprocket.created

pyproject.toml

@@ -6,7 +6,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "WuttJamaican"
-version = "0.26.0"
+version = "0.25.0"
 description = "Base package for Wutta Framework"
 readme = "README.md"
 authors = [{name = "Lance Edgar", email = "lance@wuttaproject.org"}]
@@ -27,7 +27,6 @@ classifiers = [
 requires-python = ">= 3.8"
 dependencies = [
         "bcrypt",
-        'python-dateutil; python_version < "3.9"',
         "humanize",
         'importlib-metadata; python_version < "3.10"',
         "importlib_resources ; python_version < '3.9'",
@@ -43,7 +42,7 @@ dependencies = [
 [project.optional-dependencies]
 db = ["SQLAlchemy", "alembic", "alembic-postgresql-enum"]
 docs = ["Sphinx", "sphinxcontrib-programoutput", "enum-tools[sphinx]", "furo"]
-tests = ["pylint", "pytest", "pytest-cov", "tox", "python-dateutil"]
+tests = ["pylint", "pytest", "pytest-cov", "tox"]
 
 
 [project.scripts]

src/wuttjamaican/app.py

@@ -25,7 +25,6 @@ WuttJamaican - app handler
 """
 # pylint: disable=too-many-lines
 
-import datetime
 import logging
 import os
 import sys
@@ -36,7 +35,6 @@ from importlib.metadata import version
 import humanize
 
 from wuttjamaican.util import (
-    get_timezone_by_name,
     localtime,
     load_entry_points,
     load_object,
@@ -112,7 +110,6 @@ class AppHandler:  # pylint: disable=too-many-public-methods
     def __init__(self, config):
         self.config = config
         self.handlers = {}
-        self.timezones = {}
 
     @property
     def appname(self):
@@ -531,117 +528,19 @@ class AppHandler:  # pylint: disable=too-many-public-methods
         """
         return make_full_name(*parts)
 
-    def get_timezone(self, key="default"):
+    def localtime(self, dt=None, tzinfo=True):
         """
-        Get the configured (or system default) timezone object.
-
-        This checks config for a setting which corresponds to the
-        given ``key``, then calls
-        :func:`~wuttjamaican.util.get_timezone_by_name()` to get the
-        actual timezone object.
-
-        The default key corresponds to the true "local" timezone, but
-        other keys may correspond to other configured timezones (if
-        applicable).
-
-        As a special case for the default key only: If no config value
-        is found, Python itself will determine the default system
-        local timezone.
-
-        For any non-default key, an error is raised if no config value
-        is found.
-
-        .. note::
-
-           The app handler *caches* all timezone objects, to avoid
-           unwanted repetitive lookups when processing multiple
-           datetimes etc.  (Since this method is called by
-           :meth:`localtime()`.)  Therefore whenever timezone config
-           values are changed, an app restart will be necessary.
-
-        Example config:
-
-        .. code-block:: ini
-
-           [wutta]
-           timezone.default = America/Chicago
-           timezone.westcoast = America/Los_Angeles
-
-        Example usage::
-
-           tz_default = app.get_timezone()
-           tz_westcoast = app.get_timezone("westcoast")
-
-        See also :meth:`get_timezone_name()`.
-
-        :param key: Config key for desired timezone.
-
-        :returns: :class:`python:datetime.tzinfo` instance
+        This returns a datetime in the system-local timezone.  It is a
+        convenience wrapper around
+        :func:`~wuttjamaican.util.localtime()`.
         """
-        if key not in self.timezones:
-            setting = f"{self.appname}.timezone.{key}"
-            tzname = self.config.get(setting)
-            if tzname:
-                self.timezones[key] = get_timezone_by_name(tzname)
-
-            elif key == "default":
-                # fallback to system default
-                self.timezones[key] = datetime.datetime.now().astimezone().tzinfo
-
-            else:
-                # alternate key was specified, but no config found, so check
-                # again with require() to force error
-                self.timezones[key] = self.config.require(setting)
-
-        return self.timezones[key]
-
-    def get_timezone_name(self, key="default"):
-        """
-        Get the display name for the configured (or system default)
-        timezone.
-
-        This calls :meth:`get_timezone()` and then uses some
-        heuristics to determine the name.
-
-        :param key: Config key for desired timezone.
-
-        :returns: String name for the timezone.
-        """
-        tz = self.get_timezone(key=key)
-        try:
-            # TODO: this should work for zoneinfo.ZoneInfo objects,
-            # but not sure yet about dateutils.tz ?
-            return tz.key
-        except AttributeError:
-            # this should work for system default fallback, afaik
-            dt = datetime.datetime.now(tz)
-            return dt.tzname()
-
-    def localtime(self, dt=None, local_zone=None, **kw):
-        """
-        This produces a datetime in the "local" timezone.
-
-        This is a convenience wrapper around
-        :func:`~wuttjamaican.util.localtime()`; however it also calls
-        :meth:`get_timezone()` to override the ``local_zone`` param
-        (unless caller specifies that).
-
-        For usage examples see :ref:`convert-to-localtime`.
-
-        See also :meth:`make_utc()` which is sort of the inverse.
-        """
-        kw["local_zone"] = local_zone or self.get_timezone()
-        return localtime(dt=dt, **kw)
+        return localtime(dt=dt, tzinfo=tzinfo)
 
     def make_utc(self, dt=None, tzinfo=False):
         """
         This returns a datetime local to the UTC timezone.  It is a
         convenience wrapper around
         :func:`~wuttjamaican.util.make_utc()`.
-
-        For usage examples see :ref:`convert-to-utc`.
-
-        See also :meth:`localtime()` which is sort of the inverse.
         """
         return make_utc(dt=dt, tzinfo=tzinfo)
 
@@ -896,7 +795,7 @@ class AppHandler:  # pylint: disable=too-many-public-methods
             return ""
         return value.strftime(self.display_format_date)
 
-    def render_datetime(self, value, local=True):
+    def render_datetime(self, value):
         """
         Return a human-friendly display string for the given datetime.
 
@@ -905,16 +804,14 @@ class AppHandler:  # pylint: disable=too-many-public-methods
         :param value: A :class:`python:datetime.datetime` instance (or
            ``None``).
 
-        :param local: By default the ``value`` will first be passed to
-           :meth:`localtime()` to normalize it for display.  Specify
-           ``local=False`` to skip that and render the value as-is.
-
-        :returns: Rendered datetime as string.
+        :returns: Display string.
         """
         if value is None:
             return ""
-        if local:
+
+        if not value.tzinfo:
             value = self.localtime(value)
+
         return value.strftime(self.display_format_datetime)
 
     def render_error(self, error):

src/wuttjamaican/util.py

@@ -190,93 +190,56 @@ def make_full_name(*parts):
     return " ".join(parts)
 
 
-def get_timezone_by_name(tzname):
+def localtime(dt=None, tzinfo=True):
     """
-    Retrieve a timezone object by name.
-
-    This is mostly a compatibility wrapper, since older Python is
-    missing the :mod:`python:zoneinfo` module.
-
-    For Python 3.9 and newer, this instantiates
-    :class:`python:zoneinfo.ZoneInfo`.
-
-    For Python 3.8, this calls :func:`dateutil:dateutil.tz.gettz()`.
-
-    See also :meth:`~wuttjamaican.app.AppHandler.get_timezone()` on
-    the app handler.
-
-    :param tzname: String name for timezone.
-
-    :returns: :class:`python:datetime.tzinfo` instance
-    """
-    try:
-        from zoneinfo import ZoneInfo  # pylint: disable=import-outside-toplevel
-
-        return ZoneInfo(tzname)
-
-    except ImportError:  # python 3.8
-        from dateutil.tz import gettz  # pylint: disable=import-outside-toplevel
-
-        return gettz(tzname)
-
-
-def localtime(dt=None, from_utc=True, want_tzinfo=True, local_zone=None):
-    """
-    This produces a datetime in the "local" timezone.  By default it
-    will be *zone-aware*.
+    This returns a datetime in the system-local timezone.  By default
+    it will be *zone-aware*.
 
     See also the shortcut
     :meth:`~wuttjamaican.app.AppHandler.localtime()` method on the app
-    handler.  For usage examples see :ref:`convert-to-localtime`.
+    handler.
 
     See also :func:`make_utc()` which is sort of the inverse.
 
     :param dt: Optional :class:`python:datetime.datetime` instance.
        If not specified, the current time will be used.
 
-    :param from_utc: Boolean indicating whether a naive ``dt`` is
-       already (effectively) in UTC timezone.  Set this to false when
-       providing a naive ``dt`` which is already in "local" timezone
-       instead of UTC.  This flag is ignored if ``dt`` is zone-aware.
+    :param tzinfo: Boolean indicating whether the return value should
+       have its :attr:`~python:datetime.datetime.tzinfo` attribute
+       set.  This is true by default in which case the return value
+       will be zone-aware.
 
-    :param want_tzinfo: Boolean indicating whether the resulting
-       datetime should have its
-       :attr:`~python:datetime.datetime.tzinfo` attribute set.  Set
-       this to false if you want a naive value; it's true by default,
-       for zone-aware.
-
-    :param local_zone: Optional :class:`python:datetime.tzinfo`
-       instance to use as "local" timezone, instead of relying on
-       Python to determine the system local timezone.
-
-    :returns: :class:`python:datetime.datetime` instance in local
-       timezone.
+    :returns: :class:`python:datetime.datetime` instance in
+       system-local timezone.
     """
+    # thanks to this stackoverflow post for the timezone logic,
+    # since as of now we don't have that anywhere in config.
+    # https://stackoverflow.com/a/39079819
+    # https://docs.python.org/3/library/datetime.html#datetime.datetime.astimezone
+
     # use current time if none provided
     if dt is None:
         dt = datetime.datetime.now(datetime.timezone.utc)
-
-    # set dt's timezone if needed
-    if not dt.tzinfo:
-        # UTC is default assumption unless caller says otherwise
-        if from_utc:
-            dt = dt.replace(tzinfo=datetime.timezone.utc)
-        elif local_zone:
-            dt = dt.replace(tzinfo=local_zone)
-        else:  # default system local timezone
-            tz = dt.astimezone().tzinfo
-            dt = dt.replace(tzinfo=tz)
-
-    # convert to local timezone
-    if local_zone:
-        dt = dt.astimezone(local_zone)
-    else:
         dt = dt.astimezone()
+        if tzinfo:
+            return dt
+        return dt.replace(tzinfo=None)
 
-    # maybe strip tzinfo
-    if want_tzinfo:
+    # otherwise may need to convert timezone
+    if dt.tzinfo:
+        dt = dt.astimezone()
+        if tzinfo:
+            return dt
+        return dt.replace(tzinfo=None)
+
+    # naive value returned as-is..
+    if not tzinfo:
         return dt
-    return dt.replace(tzinfo=None)
+
+    # ..unless tzinfo is wanted, in which case this assumes naive
+    # value is in the UTC timezone
+    dt = dt.replace(tzinfo=datetime.timezone.utc)
+    return dt.astimezone()
 
 
 def make_utc(dt=None, tzinfo=False):
@@ -287,7 +250,7 @@ def make_utc(dt=None, tzinfo=False):
 
     See also the shortcut
     :meth:`~wuttjamaican.app.AppHandler.make_utc()` method on the app
-    handler.  For usage examples see :ref:`convert-to-utc`.
+    handler.
 
     See also :func:`localtime()` which is sort of the inverse.
 

tests/test_app.py

@@ -16,10 +16,9 @@ from mako.template import Template
 
 import wuttjamaican.enum
 from wuttjamaican import app as mod
-from wuttjamaican.exc import ConfigurationError
 from wuttjamaican.progress import ProgressBase
 from wuttjamaican.conf import WuttaConfig
-from wuttjamaican.util import UNSPECIFIED, get_timezone_by_name
+from wuttjamaican.util import UNSPECIFIED
 from wuttjamaican.testing import FileTestCase, ConfigTestCase
 from wuttjamaican.batch import BatchHandler
 
@@ -56,7 +55,8 @@ class TestAppHandler(FileTestCase):
         self.assertIs(obj, UNSPECIFIED)
 
     def test_get_appdir(self):
-        mockdir = self.mkdtemp()
+
+        mockdir = self.mkdir("mockdir")
 
         # default appdir
         with patch.object(sys, "prefix", new=mockdir):
@@ -426,80 +426,6 @@ app_title = WuttaTest
         name = self.app.make_full_name("Fred", "", "Flintstone", "")
         self.assertEqual(name, "Fred Flintstone")
 
-    def test_get_timezone(self):
-        # cache is empty at first
-        self.assertEqual(self.app.timezones, {})
-
-        # fetch default system local timezone
-        # nb. actual value depends on machine where tests run
-        system = self.app.get_timezone()
-        self.assertIsInstance(system, datetime.tzinfo)
-        # cache no longer empty
-        self.assertEqual(len(self.app.timezones), 1)
-        self.assertIn("default", self.app.timezones)
-        self.assertIs(self.app.timezones["default"], system)
-
-        # fetch configured default
-        self.app.timezones.clear()  # clear cache
-        self.config.setdefault("wuttatest.timezone.default", "Africa/Addis_Ababa")
-        default = self.app.get_timezone()
-        self.assertIsInstance(default, datetime.tzinfo)
-        dt = datetime.datetime(2025, 12, 16, 22, 0, tzinfo=default)
-        self.assertEqual(default.utcoffset(dt), datetime.timedelta(hours=3))
-        # cache no longer empty
-        self.assertEqual(len(self.app.timezones), 1)
-        self.assertIn("default", self.app.timezones)
-        self.assertIs(self.app.timezones["default"], default)
-        # fetching again gives cached instance
-        self.assertIs(self.app.get_timezone(), default)
-
-        # fetch configured alternate
-        self.config.setdefault("wuttatest.timezone.foo", "America/New_York")
-        foo = self.app.get_timezone("foo")
-        self.assertIsInstance(foo, datetime.tzinfo)
-        self.assertIn("foo", self.app.timezones)
-        self.assertIs(self.app.timezones["foo"], foo)
-
-        # error if alternate not configured
-        self.assertRaises(ConfigurationError, self.app.get_timezone, "bar")
-        self.assertNotIn("bar", self.app.timezones)
-
-    def test_get_timezone_name(self):
-        # cache is empty at first
-        self.assertEqual(self.app.timezones, {})
-
-        # fetch default system local timezone
-        # nb. actual value depends on machine where tests run
-        system = self.app.get_timezone_name()
-        self.assertIsInstance(system, str)
-        self.assertLess(0, len(system))
-        # cache no longer empty
-        self.assertEqual(len(self.app.timezones), 1)
-        self.assertIn("default", self.app.timezones)
-
-        # fetch configured default
-        self.app.timezones.clear()  # clear cache
-        self.config.setdefault("wuttatest.timezone.default", "Africa/Addis_Ababa")
-        default = self.app.get_timezone_name()
-        # nb. this check won't work for python 3.8
-        if sys.version_info >= (3, 9):
-            self.assertEqual(default, "Africa/Addis_Ababa")
-        # cache no longer empty
-        self.assertEqual(len(self.app.timezones), 1)
-        self.assertIn("default", self.app.timezones)
-
-        # fetch configured alternate
-        self.config.setdefault("wuttatest.timezone.foo", "America/New_York")
-        foo = self.app.get_timezone_name("foo")
-        # nb. this check won't work for python 3.8
-        if sys.version_info >= (3, 9):
-            self.assertEqual(foo, "America/New_York")
-        self.assertIn("foo", self.app.timezones)
-
-        # error if alternate not configured
-        self.assertRaises(ConfigurationError, self.app.get_timezone_name, "bar")
-        self.assertNotIn("bar", self.app.timezones)
-
     def test_localtime(self):
         dt = self.app.localtime()
         self.assertIsInstance(dt, datetime.datetime)
@@ -590,38 +516,15 @@ app_title = WuttaTest
         self.assertEqual(self.app.render_date(dt), "2024-12-11")
 
     def test_render_datetime(self):
-        tzlocal = get_timezone_by_name("America/Los_Angeles")
-        with patch.object(self.app, "get_timezone", return_value=tzlocal):
+        self.assertEqual(self.app.render_datetime(None), "")
 
-            # null value
-            self.assertEqual(self.app.render_datetime(None), "")
+        dt = datetime.datetime(2024, 12, 11, 8, 30, tzinfo=datetime.timezone.utc)
+        self.assertEqual(self.app.render_datetime(dt), "2024-12-11 08:30+0000")
 
-            # naive UTC
-            dt = datetime.datetime(2024, 12, 17, 1, 12)
-            self.assertEqual(
-                self.app.render_datetime(dt, local=True), "2024-12-16 17:12-0800"
-            )
-            self.assertEqual(
-                self.app.render_datetime(dt, local=False), "2024-12-17 01:12"
-            )
-
-            # aware UTC
-            dt = datetime.datetime(2024, 12, 17, 1, 12, tzinfo=datetime.timezone.utc)
-            self.assertEqual(
-                self.app.render_datetime(dt, local=True), "2024-12-16 17:12-0800"
-            )
-            self.assertEqual(
-                self.app.render_datetime(dt, local=False), "2024-12-17 01:12+0000"
-            )
-
-            # aware local
-            dt = datetime.datetime(2024, 12, 16, 19, 12, tzinfo=tzlocal)
-            self.assertEqual(
-                self.app.render_datetime(dt, local=True), "2024-12-16 19:12-0800"
-            )
-            self.assertEqual(
-                self.app.render_datetime(dt, local=False), "2024-12-16 19:12-0800"
-            )
+        dt = datetime.datetime(2024, 12, 11, 8, 30)
+        text = self.app.render_datetime(dt)
+        # TODO: should override local timezone for more complete test
+        self.assertTrue(text.startswith("2024-12-"))
 
     def test_render_error(self):
 

tests/test_util.py

@@ -165,122 +165,49 @@ class TestLoadObject(TestCase):
         self.assertIs(result, TestCase)
 
 
-class TestGetTimezoneByName(TestCase):
-
-    def test_modern(self):
-        try:
-            import zoneinfo
-        except ImportError:
-            self.assertLess(sys.version_info, (3, 9))
-            pytest.skip("this test is not relevant before python 3.9")
-
-        tz = mod.get_timezone_by_name("America/Chicago")
-        self.assertIsInstance(tz, zoneinfo.ZoneInfo)
-        self.assertIsInstance(tz, datetime.tzinfo)
-        self.assertEqual(tz.key, "America/Chicago")
-
-    def test_legacy(self):
-        import dateutil.tz
-
-        orig_import = __import__
-
-        def mock_import(name, *args, **kwargs):
-            if name == "zoneinfo":
-                raise ImportError
-            return orig_import(name, *args, **kwargs)
-
-        with patch("builtins.__import__", side_effect=mock_import):
-            tz = mod.get_timezone_by_name("America/Chicago")
-            self.assertIsInstance(tz, dateutil.tz.tzfile)
-            self.assertIsInstance(tz, datetime.tzinfo)
-            dt = datetime.datetime.now(tz)
-            self.assertIn(dt.tzname(), ["CDT", "CST"])
-
-
 class TestLocaltime(TestCase):
 
-    def test_naive_utc(self):
-        # nb. must override local_zone for test consistency
-        tz = datetime.timezone(-datetime.timedelta(hours=5))
-        dt = datetime.datetime(2025, 12, 16, 0, 16)  # utc
-        result = mod.localtime(dt, local_zone=tz)
-        self.assertIsInstance(result, datetime.datetime)
-        self.assertIs(result.tzinfo, tz)
-        self.assertEqual(result, datetime.datetime(2025, 12, 15, 19, 16, tzinfo=tz))
-
-    def test_naive_local(self):
-        # nb. must override local_zone for test consistency
-        tz = datetime.timezone(-datetime.timedelta(hours=5))
-        dt = datetime.datetime(2025, 12, 15, 19, 16)  # local
-
-        # can test precisely when overriding local_zone
-        result = mod.localtime(dt, local_zone=tz, from_utc=False)
-        self.assertIsInstance(result, datetime.datetime)
-        self.assertIs(result.tzinfo, tz)
-        self.assertEqual(result, datetime.datetime(2025, 12, 15, 19, 16, tzinfo=tz))
-
-        # must test loosely for fallback to system local timezone
-        result = mod.localtime(dt, from_utc=False)
-        self.assertIsInstance(result, datetime.datetime)
-        self.assertIsInstance(result.tzinfo, datetime.tzinfo)
-        self.assertEqual(result.year, 2025)
-        self.assertEqual(result.month, 12)
-
-    def test_aware_utc(self):
-        # nb. must override local_zone for test consistency
-        tz = datetime.timezone(-datetime.timedelta(hours=5))
-        dt = datetime.datetime(2025, 12, 16, 0, 16, tzinfo=datetime.timezone.utc)
-        result = mod.localtime(dt, local_zone=tz)
-        self.assertIsInstance(result, datetime.datetime)
-        self.assertIs(result.tzinfo, tz)
-        self.assertEqual(result, datetime.datetime(2025, 12, 15, 19, 16, tzinfo=tz))
-
-    def test_aware_local(self):
-        # nb. must override local_zone for test consistency
-        tz = datetime.timezone(-datetime.timedelta(hours=5))
-        other = datetime.timezone(-datetime.timedelta(hours=7))
-        dt = datetime.datetime(2025, 12, 15, 17, 16, tzinfo=other)
-
-        # can test precisely when overriding local_zone
-        result = mod.localtime(dt, local_zone=tz)
-        self.assertIsInstance(result, datetime.datetime)
-        self.assertIs(result.tzinfo, tz)
-        self.assertEqual(result, datetime.datetime(2025, 12, 15, 19, 16, tzinfo=tz))
-
-        # must test loosely for fallback to system local timezone
-        result = mod.localtime(dt)
-        self.assertIsInstance(result, datetime.datetime)
-        self.assertIsInstance(result.tzinfo, datetime.tzinfo)
-        self.assertEqual(result.year, 2025)
-        self.assertEqual(result.month, 12)
-
     def test_current_time(self):
-        tz = datetime.timezone(-datetime.timedelta(hours=5))
 
-        # overriding local_zone
-        result = mod.localtime(local_zone=tz)
-        self.assertIsInstance(result, datetime.datetime)
-        self.assertIs(result.tzinfo, tz)
-
-        # fallback to system local timezone
-        result = mod.localtime()
-        self.assertIsInstance(result, datetime.datetime)
-        self.assertIsInstance(result.tzinfo, datetime.tzinfo)
-        self.assertIsNot(result.tzinfo, tz)
-
-    def test_want_tzinfo(self):
-
-        # wants tzinfo implicitly
-        result = mod.localtime()
-        self.assertIsInstance(result.tzinfo, datetime.tzinfo)
-
-        # wants tzinfo explicitly
-        result = mod.localtime(want_tzinfo=True)
-        self.assertIsInstance(result.tzinfo, datetime.tzinfo)
+        # has tzinfo by default
+        dt = mod.localtime()
+        self.assertIsInstance(dt, datetime.datetime)
+        self.assertIsNotNone(dt.tzinfo)
+        now = datetime.datetime.now()
+        self.assertAlmostEqual(int(dt.timestamp()), int(now.timestamp()))
 
         # no tzinfo
-        result = mod.localtime(want_tzinfo=False)
-        self.assertIsNone(result.tzinfo)
+        dt = mod.localtime(tzinfo=False)
+        self.assertIsInstance(dt, datetime.datetime)
+        self.assertIsNone(dt.tzinfo)
+        now = datetime.datetime.now()
+        self.assertAlmostEqual(int(dt.timestamp()), int(now.timestamp()))
+
+    def test_convert_with_tzinfo(self):
+        sample = datetime.datetime(2024, 9, 15, 13, 30, tzinfo=datetime.timezone.utc)
+
+        # has tzinfo by default
+        dt = mod.localtime(sample)
+        self.assertIsInstance(dt, datetime.datetime)
+        self.assertIsNotNone(dt.tzinfo)
+
+        # no tzinfo
+        dt = mod.localtime(sample, tzinfo=False)
+        self.assertIsInstance(dt, datetime.datetime)
+        self.assertIsNone(dt.tzinfo)
+
+    def test_convert_without_tzinfo(self):
+        sample = datetime.datetime(2024, 9, 15, 13, 30)
+
+        # has tzinfo by default
+        dt = mod.localtime(sample)
+        self.assertIsInstance(dt, datetime.datetime)
+        self.assertIsNotNone(dt.tzinfo)
+
+        # no tzinfo
+        dt = mod.localtime(sample, tzinfo=False)
+        self.assertIsInstance(dt, datetime.datetime)
+        self.assertIsNone(dt.tzinfo)
 
 
 class TestMakeUTC(TestCase):