Fix discontinuous hub chart candles from orphaned DB bars.

Keep only the latest contiguous K-line segment, purge isolated stale rows, and backfill when the tail is still shorter than the initial limit.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/test_hub_kline_store.py

@@ -14,6 +14,7 @@ from hub_kline_store import (
     purge_timeframe_by_days,
     resolve_chart_bars,
     retention_days,
+    trim_contiguous_tail,
     upsert_bars,
 )
 from hub_ohlcv_lib import (
@@ -190,6 +191,92 @@ class TestHubKlineStore(unittest.TestCase):
         self.assertEqual(len(got), 2)
         self.assertEqual(got[-1]["open_time_ms"], base + 2 * period)
 
+    def test_trim_contiguous_tail_drops_orphan_prefix(self):
+        period = TIMEFRAME_MS["15m"]
+        base_old = 1_700_000_000_000
+        base_new = base_old + period * 500
+        bars = []
+        for i in range(3):
+            bars.append(
+                {
+                    "open_time_ms": base_old + i * period,
+                    "open": 1,
+                    "high": 2,
+                    "low": 0.5,
+                    "close": 1.5,
+                    "volume": 1,
+                }
+            )
+        for i in range(5):
+            bars.append(
+                {
+                    "open_time_ms": base_new + i * period,
+                    "open": 2,
+                    "high": 3,
+                    "low": 1.5,
+                    "close": 2.5,
+                    "volume": 2,
+                }
+            )
+        trimmed, split = trim_contiguous_tail(bars, period)
+        self.assertEqual(split, 3)
+        self.assertEqual(len(trimmed), 5)
+        self.assertEqual(trimmed[0]["open_time_ms"], base_new)
+
+    def test_resolve_drops_discontinuous_orphans(self):
+        init_db(self.db)
+        period = TIMEFRAME_MS["15m"]
+        now = int(time.time() * 1000)
+        old_ms = now - period * 800
+        upsert_bars(
+            "okx",
+            "ONDO/USDT",
+            "15m",
+            [
+                {
+                    "open_time_ms": old_ms,
+                    "open": 0.33,
+                    "high": 0.34,
+                    "low": 0.32,
+                    "close": 0.335,
+                    "volume": 100,
+                }
+            ],
+            self.db,
+        )
+        recent = []
+        start = now - period * 20
+        for i in range(20):
+            recent.append(
+                {
+                    "open_time_ms": start + i * period,
+                    "open": 0.35,
+                    "high": 0.36,
+                    "low": 0.34,
+                    "close": 0.355,
+                    "volume": 50,
+                }
+            )
+
+        def remote_fetch(**kwargs):
+            return {"ok": True, "bars": recent, "price_tick": 0.0001}
+
+        out = resolve_chart_bars(
+            "okx",
+            "ONDO/USDT",
+            "15m",
+            remote_fetch,
+            db_path=self.db,
+            limit=50,
+        )
+        self.assertTrue(out.get("ok"))
+        candles = out.get("candles") or []
+        self.assertGreaterEqual(len(candles), 19)
+        if len(candles) >= 2:
+            for i in range(1, len(candles)):
+                gap = candles[i]["time"] - candles[i - 1]["time"]
+                self.assertLessEqual(gap, int(period / 1000 * 1.5))
+
     def test_resolve_before_ms_exhausted(self):
         init_db(self.db)