feat: add week boundary computation with DST handling

Made-with: Cursor

tests/test_week.py

@@ -0,0 +1,38 @@
+from datetime import datetime, timezone
+
+from ntr_fetcher.week import get_show_week, SHOW_DAY_DEFAULT, SHOW_HOUR_DEFAULT
+
+
+def test_mid_week_thursday():
+    """Thursday should belong to the show that started the previous Wednesday."""
+    # 2025-03-13 is Thursday (2026-03-13 is Friday)
+    now = datetime(2025, 3, 13, 15, 0, 0, tzinfo=timezone.utc)
+    start, end = get_show_week(now, show_day=2, show_hour=22)
+    assert start == datetime(2025, 3, 13, 2, 0, 0, tzinfo=timezone.utc)
+    assert end == datetime(2025, 3, 20, 2, 0, 0, tzinfo=timezone.utc)
+
+
+def test_wednesday_before_show():
+    """Wednesday before 22:00 ET belongs to the previous week's show."""
+    # 2025-03-12 is Wednesday
+    now = datetime(2025, 3, 12, 20, 0, 0, tzinfo=timezone.utc)
+    start, end = get_show_week(now, show_day=2, show_hour=22)
+    assert start == datetime(2025, 3, 6, 3, 0, 0, tzinfo=timezone.utc)
+    assert end == datetime(2025, 3, 13, 2, 0, 0, tzinfo=timezone.utc)
+
+
+def test_wednesday_after_show_starts():
+    """Wednesday at or after 22:00 ET belongs to the new week."""
+    # 2025-03-13 02:30 UTC = Wed 2025-03-12 22:30 ET
+    now = datetime(2025, 3, 13, 2, 30, 0, tzinfo=timezone.utc)
+    start, end = get_show_week(now, show_day=2, show_hour=22)
+    assert start == datetime(2025, 3, 13, 2, 0, 0, tzinfo=timezone.utc)
+    assert end == datetime(2025, 3, 20, 2, 0, 0, tzinfo=timezone.utc)
+
+
+def test_est_period_no_dst():
+    """January — firmly in EST (UTC-5)."""
+    now = datetime(2026, 1, 15, 12, 0, 0, tzinfo=timezone.utc)
+    start, end = get_show_week(now, show_day=2, show_hour=22)
+    assert start == datetime(2026, 1, 15, 3, 0, 0, tzinfo=timezone.utc)
+    assert end == datetime(2026, 1, 22, 3, 0, 0, tzinfo=timezone.utc)