--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/unit/test_plugin_xep_0082.py	Tue Aug 23 12:04:11 2022 +0200
@@ -0,0 +1,204 @@
+#!/usr/bin/env python3
+
+# Tests for Libervia's XMPP Date and Time Profile formatting and parsing plugin
+# Copyright (C) 2022-2022 Tim Henkes (me@syndace.dev)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Type-check with `mypy --strict`
+# Lint with `pylint`
+
+from datetime import date, datetime, time, timezone
+
+import pytest
+
+from sat.plugins.plugin_xep_0082 import XEP_0082
+
+
+__all__ = [  # pylint: disable=unused-variable
+    "test_date_formatting",
+    "test_date_parsing",
+    "test_datetime_formatting",
+    "test_datetime_parsing",
+    "test_time_formatting",
+    "test_time_parsing"
+]
+
+
+def test_date_formatting() -> None:  # pylint: disable=missing-function-docstring
+    # The following tests don't check the output of format_date directly; instead, they
+    # assume that parse_date rejects incorrect formatting.
+
+    # The date version 0.1 of XEP-0082 was published
+    value = date(2003, 4, 21)
+
+    # Check that the parsed date equals the formatted date
+    assert XEP_0082.parse_date(XEP_0082.format_date(value)) == value
+
+    # Check that a date instance is returned when format_date is called without an
+    # explicit input date
+    assert isinstance(XEP_0082.parse_date(XEP_0082.format_date()), date)
+
+
+def test_date_parsing() -> None:  # pylint: disable=missing-function-docstring
+    # There isn't really a point in testing much more than this
+    assert XEP_0082.parse_date("2003-04-21") == date(2003, 4, 21)
+
+
+def test_datetime_formatting() -> None:  # pylint: disable=missing-function-docstring
+    # The following tests don't check the output of format_datetime directly; instead,
+    # they assume that parse_datetime rejects incorrect formatting.
+
+    # A datetime in UTC
+    value = datetime(1234, 5, 6, 7, 8, 9, 123456, timezone.utc)
+
+    # Check that the parsed datetime equals the formatted datetime except for the
+    # microseconds
+    parsed = XEP_0082.parse_datetime(XEP_0082.format_datetime(value))
+    assert parsed != value
+    assert parsed.replace(microsecond=123456) == value
+
+    # Check that the parsed datetime equals the formatted datetime including microseconds
+    assert XEP_0082.parse_datetime(XEP_0082.format_datetime(value, True)) == value
+
+    # A datetime in some other timezone, from the Python docs of the datetime module
+    value = datetime.fromisoformat("2011-11-04T00:05:23+04:00")
+
+    # Check that the parsed datetime equals the formatted datetime with or without
+    # microseconds
+    assert XEP_0082.parse_datetime(XEP_0082.format_datetime(value)) == value
+    assert XEP_0082.parse_datetime(XEP_0082.format_datetime(value, True)) == value
+
+    # Check that the datetime was converted to UTC while formatting
+    assert XEP_0082.parse_datetime(XEP_0082.format_datetime(value)).tzinfo == timezone.utc
+
+    # Check that a datetime instance is returned when format_datetime is called without an
+    # explicit input
+    # datetime
+    assert isinstance(XEP_0082.parse_datetime(XEP_0082.format_datetime()), datetime)
+    assert isinstance(XEP_0082.parse_datetime(XEP_0082.format_datetime(
+        include_microsecond=True
+    )), datetime)
+    assert XEP_0082.parse_datetime(XEP_0082.format_datetime()).tzinfo == timezone.utc
+
+
+def test_datetime_parsing() -> None:  # pylint: disable=missing-function-docstring
+    # Datetime of the first human steps on the Moon (UTC)
+    value = datetime(1969, 7, 21, 2, 56, 15, tzinfo=timezone.utc)
+
+    # With timezone 'Z', without a fraction of a second
+    assert XEP_0082.parse_datetime("1969-07-21T02:56:15Z") == value
+
+    # With timezone '+04:00', without a fraction of a second
+    assert XEP_0082.parse_datetime("1969-07-21T06:56:15+04:00") == value
+
+    # With timezone '-05:00', without a fraction of a second
+    assert XEP_0082.parse_datetime("1969-07-20T21:56:15-05:00") == value
+
+    # Without timezone, without a fraction of a second
+    with pytest.raises(ValueError):
+        XEP_0082.parse_datetime("1969-07-21T02:56:15")
+
+    # With timezone 'Z', with a fraction of a second consisting of two digits
+    assert XEP_0082.parse_datetime("1969-07-21T02:56:15.12Z") == \
+        value.replace(microsecond=120000)
+
+    # With timezone 'Z', with a fraction of a second consisting of nine digits
+    assert XEP_0082.parse_datetime("1969-07-21T02:56:15.123456789Z") == \
+        value.replace(microsecond=123456)
+
+    # With timezone '+04:00', with a fraction of a second consisting of six digits
+    assert XEP_0082.parse_datetime("1969-07-21T06:56:15.123456+04:00") == \
+        value.replace(microsecond=123456)
+
+    # With timezone '-05:00', with a fraction of a second consisting of zero digits
+    assert XEP_0082.parse_datetime("1969-07-20T21:56:15.-05:00") == value
+
+    # Without timezone, with a fraction of a second consisting of six digits
+    with pytest.raises(ValueError):
+        XEP_0082.parse_datetime("1969-07-21T02:56:15.123456")
+
+
+def test_time_formatting() -> None:  # pylint: disable=missing-function-docstring
+    # The following tests don't check the output of format_time directly; instead, they
+    # assume that parse_time rejects incorrect formatting.
+
+    # A time in UTC
+    value = time(12, 34, 56, 789012, timezone.utc)
+
+    # Check that the parsed time equals the formatted time except for the microseconds
+    parsed = XEP_0082.parse_time(XEP_0082.format_time(value))
+    assert parsed != value
+    assert parsed.replace(microsecond=789012) == value
+
+    # Check that the parsed time equals the formatted time including microseconds
+    assert XEP_0082.parse_time(XEP_0082.format_time(value, True)) == value
+
+    # A time in some other timezone, from the Python docs of the datetime module
+    value = time.fromisoformat("04:23:01+04:00")
+
+    # Check that the parsed time equals the formatted time with or without microseconds
+    assert XEP_0082.parse_time(XEP_0082.format_time(value)) == value
+    assert XEP_0082.parse_time(XEP_0082.format_time(value, True)) == value
+
+    # Check that the time has retained its timezone
+    assert XEP_0082.parse_time(XEP_0082.format_time(value)).tzinfo == value.tzinfo
+
+    # A time without timezone information, from the Python docs of the datetime module
+    value = time.fromisoformat("04:23:01")
+
+    # Check that the parsed time doesn't have timezone information either
+    assert XEP_0082.parse_time(XEP_0082.format_time(value)).tzinfo is None
+
+    # Check that a time instance is returned when format_time is called without an
+    # explicit input date
+    assert isinstance(XEP_0082.parse_time(XEP_0082.format_time()), time)
+    assert isinstance(XEP_0082.parse_time(XEP_0082.format_time(
+        include_microsecond=True
+    )), time)
+    assert XEP_0082.parse_time(XEP_0082.format_time()).tzinfo == timezone.utc
+
+
+def test_time_parsing() -> None:  # pylint: disable=missing-function-docstring
+    # Time for tea
+    value = time(16, 0, 0, tzinfo=timezone.utc)
+
+    # With timezone 'Z', without a fraction of a second
+    assert XEP_0082.parse_time("16:00:00Z") == value
+
+    # With timezone '+04:00', without a fraction of a second
+    assert XEP_0082.parse_time("20:00:00+04:00") == value
+
+    # With timezone '-05:00', without a fraction of a second
+    assert XEP_0082.parse_time("11:00:00-05:00") == value
+
+    # Without a timezone, without a fraction of a second
+    assert XEP_0082.parse_time("16:00:00") == value.replace(tzinfo=None)
+
+    # With timezone 'Z', with a fraction of a second consisting of two digits
+    assert XEP_0082.parse_time("16:00:00.12Z") == value.replace(microsecond=120000)
+
+    # With timezone 'Z', with a fraction of a second consisting of nine digits
+    assert XEP_0082.parse_time("16:00:00.123456789Z") == value.replace(microsecond=123456)
+
+    # With timezone '+04:00', with a fraction of a second consisting of six digits
+    assert XEP_0082.parse_time("20:00:00.123456+04:00") == \
+        value.replace(microsecond=123456)
+
+    # With timezone '-05:00', with a fraction of a second consisting of zero digits
+    assert XEP_0082.parse_time("11:00:00.-05:00") == value
+
+    # Without a timezone, with a fraction of a second consisting of six digits
+    assert XEP_0082.parse_time("16:00:00.123456") == \
+        value.replace(microsecond=123456, tzinfo=None)