1 files changed, 179 insertions, 0 deletions
diff --git a/tests/test_helpers.py b/tests/test_helpers.py
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+++ b/tests/test_helpers.py
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+from __future__ import annotations
+
+from datetime import datetime
+
+import pytest
+import pytz
+
+import pendulum
+
+from pendulum import timezone
+from pendulum.helpers import days_in_year
+from pendulum.helpers import precise_diff
+from pendulum.helpers import week_day
+
+
+def assert_diff(
+    diff, years=0, months=0, days=0, hours=0, minutes=0, seconds=0, microseconds=0
+):
+    assert diff.years == years
+    assert diff.months == months
+    assert diff.days == days
+    assert diff.hours == hours
+    assert diff.minutes == minutes
+    assert diff.seconds == seconds
+    assert diff.microseconds == microseconds
+
+
+def test_precise_diff():
+    dt1 = datetime(2003, 3, 1, 0, 0, 0)
+    dt2 = datetime(2003, 1, 31, 23, 59, 59)
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(diff, months=-1, seconds=-1)
+
+    diff = precise_diff(dt2, dt1)
+    assert_diff(diff, months=1, seconds=1)
+
+    dt1 = datetime(2012, 3, 1, 0, 0, 0)
+    dt2 = datetime(2012, 1, 31, 23, 59, 59)
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(diff, months=-1, seconds=-1)
+
+    diff = precise_diff(dt2, dt1)
+    assert_diff(diff, months=1, seconds=1)
+
+    dt1 = datetime(2001, 1, 1)
+    dt2 = datetime(2003, 9, 17, 20, 54, 47, 282310)
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(
+        diff,
+        years=2,
+        months=8,
+        days=16,
+        hours=20,
+        minutes=54,
+        seconds=47,
+        microseconds=282310,
+    )
+
+    dt1 = datetime(2017, 2, 17, 16, 5, 45, 123456)
+    dt2 = datetime(2018, 2, 17, 16, 5, 45, 123256)
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(
+        diff, months=11, days=30, hours=23, minutes=59, seconds=59, microseconds=999800
+    )
+
+    # DST
+    tz = timezone("America/Toronto")
+    dt1 = tz.datetime(2017, 3, 7)
+    dt2 = tz.datetime(2017, 3, 13)
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(diff, days=6, hours=0)
+
+
+def test_precise_diff_timezone():
+    paris = pendulum.timezone("Europe/Paris")
+    toronto = pendulum.timezone("America/Toronto")
+
+    dt1 = paris.datetime(2013, 3, 31, 1, 30)
+    dt2 = paris.datetime(2013, 4, 1, 1, 30)
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(diff, days=1, hours=0)
+
+    dt2 = toronto.datetime(2013, 4, 1, 1, 30)
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(diff, days=1, hours=5)
+
+    # pytz
+    paris = pytz.timezone("Europe/Paris")
+    toronto = pytz.timezone("America/Toronto")
+
+    dt1 = paris.localize(datetime(2013, 3, 31, 1, 30))
+    dt2 = paris.localize(datetime(2013, 4, 1, 1, 30))
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(diff, days=1, hours=0)
+
+    dt2 = toronto.localize(datetime(2013, 4, 1, 1, 30))
+
+    diff = precise_diff(dt1, dt2)
+    assert_diff(diff, days=1, hours=5)
+
+    # Issue238
+    dt1 = timezone("UTC").datetime(2018, 6, 20, 1, 30)
+    dt2 = timezone("Europe/Paris").datetime(2018, 6, 20, 3, 40)  # UTC+2
+    diff = precise_diff(dt1, dt2)
+    assert_diff(diff, minutes=10)
+
+
+def test_week_day():
+    assert week_day(2017, 6, 2) == 5
+    assert week_day(2017, 1, 1) == 7
+
+
+def test_days_in_years():
+    assert days_in_year(2017) == 365
+    assert days_in_year(2016) == 366
+
+
+def test_locale():
+    dt = pendulum.datetime(2000, 11, 10, 12, 34, 56, 123456)
+    pendulum.set_locale("fr")
+
+    assert pendulum.get_locale() == "fr"
+
+    assert dt.format("MMMM") == "novembre"
+    assert dt.date().format("MMMM") == "novembre"
+
+
+def test_set_locale_invalid():
+    with pytest.raises(ValueError):
+        pendulum.set_locale("invalid")
+
+
+@pytest.mark.parametrize(
+    "locale", ["DE", "pt-BR", "pt-br", "PT-br", "PT-BR", "pt_br", "PT_BR", "PT_BR"]
+)
+def test_set_locale_malformed_locale(locale):
+    pendulum.set_locale(locale)
+
+    pendulum.set_locale("en")
+
+
+def test_week_starts_at():
+    pendulum.week_starts_at(pendulum.SATURDAY)
+
+    dt = pendulum.now().start_of("week")
+    assert dt.day_of_week == pendulum.SATURDAY
+    assert dt.date().day_of_week == pendulum.SATURDAY
+
+
+def test_week_starts_at_invalid_value():
+    with pytest.raises(ValueError):
+        pendulum.week_starts_at(-1)
+
+    with pytest.raises(ValueError):
+        pendulum.week_starts_at(11)
+
+
+def test_week_ends_at():
+    pendulum.week_ends_at(pendulum.SATURDAY)
+
+    dt = pendulum.now().end_of("week")
+    assert dt.day_of_week == pendulum.SATURDAY
+    assert dt.date().day_of_week == pendulum.SATURDAY
+
+
+def test_week_ends_at_invalid_value():
+    with pytest.raises(ValueError):
+        pendulum.week_ends_at(-1)
+
+    with pytest.raises(ValueError):
+        pendulum.week_ends_at(11)