feat(data): T4 backfill lane ①ann_meta ②news_meta 落地 [nas]

spec §18.7 T4(unit marker 断点+--limit 冒烟不落marker+墙钟rc3 全链复用):
- ①ann_meta 回补: unit=(stock,year) 2000→今年逐年按池序, 空年=合法done
  (探测优先);今年窗口右端=today 相对;~15万 unit @1s≈3-6 跑日
- ②news_meta 回补: np-listapi unit=(stock,page) 翻到空页止;空页+page≥200
  双止条件都落 news_end 哨兵(到头股零重扫);mkt前缀 6→1/其余→0
- 共用 _absorb_new(daily/backfill 同一条 id 去重+追加管道)
- 测试 46 个;修 wiring 网络泄漏:_wire_backfill_ann 曾漏锁
  fetch_news_backfill_page 致 ann 测试真打 np-listapi(40s/真出网,
  零网络铁律违反)——补锁后套件 159s→1.3s;全套 263 绿

tests/data_platform/test_corpus_download.py

@@ -532,3 +532,154 @@ def test_main_daily_exit0(root, monkeypatch):
     with pytest.raises(SystemExit) as e:
         cd.main()
     assert e.value.code == 0
+
+
+# ---------- backfill lane ①ann_meta ②news_meta(T4) ----------
+
+def _wire_backfill_ann(monkeypatch, rows_by_unit):
+    """rows_by_unit: {(code, start, end): rows} — 按 unit 窗口回放。
+    必须同时锁死 news 段 fetch(零网络铁律——曾漏锁致真打 np-listapi 40s)。"""
+    monkeypatch.setattr(cd, "load_stock_pool", lambda **kw: POOL)
+    monkeypatch.setattr(cd, "fetch_news_backfill_page", MagicMock(return_value=[]))
+    calls = []
+
+    def fake(client, code, org, start, end, category=""):
+        calls.append((code, start, end))
+        return rows_by_unit.get((code, start, end), [])
+
+    monkeypatch.setattr(cd, "fetch_cninfo_announcements", fake)
+    return calls
+
+
+def test_backfill_ann_units_walk_years_asc_from_2000(root, monkeypatch):
+    """unit=(stock,year), 2000→今年逐年, 每年内按池序; 空年=合法 done。"""
+    import pandas as pd
+    calls = _wire_backfill_ann(monkeypatch, {("000001", "2001-01-01", "2001-12-31"):
+                                             [_ann_raw(aid="b1")]})
+    rc = cd.run_lane("backfill")
+    assert rc == 0
+    t = dt.date.today()
+    n_years = t.year - 2000 + 1
+    assert len(calls) == n_years * 2            # 每股每年 1 req(空窗 1 页即返)
+    assert calls[0] == ("000001", "2000-01-01", "2000-12-31")
+    assert calls[-1][1].startswith(t.isoformat()[:4])   # 今年
+    # 今年窗口右端=今天(相对), 历年=12-31
+    assert calls[-1][2] == t.isoformat()
+    assert cd.is_done("backfill", "ann", "000001_2001")
+    assert cd.is_done("backfill", "ann", "000001_2000")  # 空年也 done
+    today = t.isoformat()
+    ann = pd.read_parquet(root / "ann_meta" / f"dt={today}" / "part-0.parquet")
+    assert len(ann) == 1 and ann.iloc[0]["announcement_id"] == "b1"
+
+
+def test_backfill_ann_marker_skip_on_rerun(root, monkeypatch):
+    """done unit 零重拉(断点续传实证之 mock 版);数据幂等零重复。"""
+    import pandas as pd
+    _wire_backfill_ann(monkeypatch, {("000001", "2001-01-01", "2001-12-31"):
+                                     [_ann_raw(aid="b1")]})
+    cd.run_lane("backfill")
+    calls2 = _wire_backfill_ann(monkeypatch, {("000001", "2001-01-01", "2001-12-31"):
+                                              [_ann_raw(aid="b1")]})
+    cd.run_lane("backfill")
+    assert calls2 == []                          # 全部 done → 零请求
+    today = dt.date.today().isoformat()
+    ann = pd.read_parquet(root / "ann_meta" / f"dt={today}" / "part-0.parquet")
+    assert len(ann) == 1
+
+
+def test_backfill_ann_resume_from_oldest_undone(root, monkeypatch):
+    """手动标 2000/2001 done → 重跑只碰 2002 起。"""
+    cd.mark_done("backfill", "ann", "000001_2000")
+    cd.mark_done("backfill", "ann", "000001_2001")
+    cd.mark_done("backfill", "ann", "600519_2000")
+    cd.mark_done("backfill", "ann", "600519_2001")
+    calls = _wire_backfill_ann(monkeypatch, {})
+    cd.run_lane("backfill")
+    starts = {c[1] for c in calls}
+    assert "2000-01-01" not in starts and "2001-01-01" not in starts
+
+
+def test_backfill_ann_unit_fail_not_marked(root, monkeypatch):
+    calls = _wire_backfill_ann(monkeypatch, {})
+    monkeypatch.setattr(cd, "fetch_cninfo_announcements",
+                        MagicMock(side_effect=cd.TransportError("boom")))
+    rc = cd.run_lane("backfill")
+    assert rc == 1
+    assert not cd.is_done("backfill", "ann", "000001_2000")
+
+
+def _wire_news_backfill(monkeypatch, pages):
+    """pages: {page_idx: rows} — 翻页回放。"""
+    monkeypatch.setattr(cd, "load_stock_pool", lambda **kw: [("600519", "o1")])
+    monkeypatch.setattr(cd, "fetch_cninfo_announcements",
+                        MagicMock(return_value=[]))
+    urls = []
+
+    def fake(client, code, mkt, page):
+        urls.append((code, mkt, page))
+        return pages.get(page, [])
+
+    monkeypatch.setattr(cd, "fetch_news_backfill_page", fake)
+    return urls
+
+
+def test_backfill_news_walks_pages_until_empty(root, monkeypatch):
+    import pandas as pd
+    np_rows = [{"Art_Code": f"a{i}", "Art_ShowTime": f"2024-01-0{i} 00:00:00",
+                "Art_Title": f"t{i}", "Art_Url": f"http://x/a{i}.html",
+                "Np_dst": "CMS"} for i in (1, 2, 3)]
+    urls = _wire_news_backfill(monkeypatch, {1: np_rows[:2], 2: np_rows[2:]})
+    rc = cd.run_lane("backfill")
+    assert rc == 0
+    assert urls[:2] == [("600519", "1", 1), ("600519", "1", 2)]
+    assert urls[2] == ("600519", "1", 3)         # 第3页空 → 止
+    assert len(urls) == 3
+    assert cd.is_done("backfill", "news", "600519_p1")
+    assert cd.is_done("backfill", "news_end", "600519")   # 空页=股票到头
+    today = dt.date.today().isoformat()
+    news = pd.read_parquet(root / "news_meta" / f"dt={today}" / "part-0.parquet")
+    assert len(news) == 3
+    assert news.iloc[0]["summary"] is None       # np 段无摘要如实
+
+
+def test_backfill_news_end_sentinel_skips_stock(root, monkeypatch):
+    cd.mark_done("backfill", "news_end", "600519")
+    urls = _wire_news_backfill(monkeypatch, {1: ["x"]})
+    cd.run_lane("backfill")
+    assert urls == []                            # 到头股零请求
+
+
+def test_backfill_news_page_cap_200(root, monkeypatch):
+    """page≥200 止(实测硬顶), 到 200 即算该股完结。"""
+    row = {"Art_Code": "a", "Art_ShowTime": "2020-01-01 00:00:00",
+           "Art_Title": "t", "Art_Url": "http://x/a.html", "Np_dst": "CMS"}
+    urls = _wire_news_backfill(monkeypatch,
+                               {p: [dict(row)] for p in range(1, 201)})
+    cd.run_lane("backfill")
+    assert len(urls) == 200
+    assert cd.is_done("backfill", "news_end", "600519")
+
+
+def test_backfill_news_mkt_prefix_mapping(root, monkeypatch):
+    urls = _wire_news_backfill(monkeypatch, {})
+    cd.run_lane("backfill")
+    assert urls[0][1] == "1"                     # 600519 → SH=1
+    urls2 = _wire_news_backfill(monkeypatch, {})  # 只换 fetch 窗口
+    monkeypatch.setattr(cd, "load_stock_pool", lambda **kw: [("000001", "o")])
+    cd.run_lane("backfill")
+    assert urls2[0][1] == "0"                    # 000001 → SZ=0
+
+
+def test_backfill_limit_smoke_no_markers(root, monkeypatch):
+    _wire_backfill_ann(monkeypatch, {})
+    rc = cd.run_lane("backfill", limit=3)
+    assert rc == 0
+    assert not any((root / "state" / "markers" / "backfill").rglob("*.done"))
+
+
+def test_backfill_wallclock_rc3(root, monkeypatch):
+    _wire_backfill_ann(monkeypatch, {})
+    past = (dt.datetime.now() - dt.timedelta(minutes=1)).strftime("%H:%M")
+    rc = cd.run_lane("backfill", until=past)
+    assert rc == 3
+    assert cd.is_done("backfill", "ann", "000001_2000")  # 首 unit 完成后停