feat: fechas aproximadas gratis en discovery (approximate_date) con upgrade a real al extraer

tests/test_approx_dates.py

@@ -0,0 +1,93 @@
+"""Fechas aproximadas de discovery: bandera upload_date_approx.
+
+Matriz de precedencia de upsert_videos + upgrade approx->real de
+set_upload_date + conversion timestamp -> YYYYMMDD en discover.
+Spec: docs/superpowers/specs/2026-08-22-approximate-upload-dates-design.md
+"""
+
+from yt_scraper.store import Store, VideoRef
+
+
+def _ref(vid, date=None, approx=0, ch="ch1"):
+    return VideoRef(
+        video_id=vid,
+        channel_id=ch,
+        title="t " + vid,
+        url=f"https://youtu.be/{vid}",
+        upload_date=date,
+        date_approx=approx,
+    )
+
+
+def _store(tmp_path):
+    s = Store(tmp_path / "test.db")
+    s.upsert_channel("ch1", None, "Canal de prueba")
+    return s
+
+
+def test_approx_into_empty(tmp_path):
+    s = _store(tmp_path)
+    s.upsert_videos([_ref("v1", date="20260820", approx=1)])
+    row = s.get_video("v1")
+    assert row.upload_date == "20260820"
+    assert row.upload_date_approx == 1
+
+
+def test_real_not_downgraded_by_approx(tmp_path):
+    s = _store(tmp_path)
+    s.upsert_videos([_ref("v1", date="20240101", approx=0)])
+    s.upsert_videos([_ref("v1", date="20260820", approx=1)])
+    row = s.get_video("v1")
+    assert row.upload_date == "20240101"
+    assert row.upload_date_approx == 0
+
+
+def test_approx_refreshed_by_newer_approx(tmp_path):
+    s = _store(tmp_path)
+    s.upsert_videos([_ref("v1", date="20260101", approx=1)])
+    s.upsert_videos([_ref("v1", date="20260820", approx=1)])
+    row = s.get_video("v1")
+    assert row.upload_date == "20260820"
+    assert row.upload_date_approx == 1
+
+
+def test_extraction_upgrades_approx_to_real(tmp_path):
+    s = _store(tmp_path)
+    s.upsert_videos([_ref("v1", date="20260820", approx=1)])
+    s.set_upload_date("v1", "20260818")
+    row = s.get_video("v1")
+    assert row.upload_date == "20260818"
+    assert row.upload_date_approx == 0
+
+
+def test_set_upload_date_still_skips_existing_real(tmp_path):
+    s = _store(tmp_path)
+    s.upsert_videos([_ref("v1", date="20240101", approx=0)])
+    s.set_upload_date("v1", "20260818")
+    assert s.get_video("v1").upload_date == "20240101"
+
+
+def test_migration_defaults_flag_to_zero(tmp_path):
+    # Filas creadas por la via vieja (INSERT sin la columna) quedan con 0.
+    s = _store(tmp_path)
+    s.upsert_videos([_ref("v2", date=None, approx=0)])
+    row = s.get_video("v2")
+    assert not row.upload_date_approx
+
+
+# --- conversion en discover -------------------------------------------------
+
+from yt_scraper.discover import _entry_upload_date
+
+
+def test_entry_upload_date_prefers_exact():
+    assert _entry_upload_date({"upload_date": "20240101"}) == ("20240101", 0)
+
+
+def test_entry_upload_date_from_timestamp():
+    ts = 1716115200  # 2024-05-19 12:00 UTC
+    assert _entry_upload_date({"timestamp": ts}) == ("20240519", 1)
+
+
+def test_entry_upload_date_none():
+    assert _entry_upload_date({}) == (None, 0)