B-44: 返修——多币种对方汇总、镜像科目筛选、冲销独立生效日、创建来源撤销边界与并发幂等

tests/test_positions.py

@@ -267,6 +267,47 @@ class UnresolvedTests(LedgerBase):
 
 
 class PaginationTests(LedgerBase):
+    def test_subject_filter_matches_stored_and_mirror_subjects(self) -> None:
+        # A books "receivable" from its own perspective; B sees the mirror
+        # "payable". Filtering by B's mirror subject must still find the event.
+        self.pair(self.company_a, self.company_b, "100.00")
+        ledger_events.reconcile_bank_events(self.connection, actor=self.admin)
+        event_id = self.ledger_events()[0]["id"]
+        confirm(self.connection, event_id, self.company_a, "receivable", "k-mirror",
+                self.admin)
+
+        stored = positions.list_events(
+            self.connection, from_="2026-01-01", cutoff="2026-07-31",
+            subject="receivable",
+        )
+        self.assertTrue(any(
+            item["ledger_event_id"] == event_id for item in stored["items"]
+        ))
+        # Company B filters by its own perspective: the stored "receivable" is
+        # the mirror of "payable", so it must be included.
+        mirror = positions.list_events(
+            self.connection, from_="2026-01-01", cutoff="2026-07-31",
+            subject="payable", viewer_company_id=self.company_b,
+        )
+        self.assertTrue(any(
+            item["ledger_event_id"] == event_id for item in mirror["items"]
+        ), mirror)
+        for item in mirror["items"]:
+            if item["ledger_event_id"] == event_id:
+                self.assertEqual("payable", item["own_subject"])
+
+    def test_subject_filter_without_match_returns_empty(self) -> None:
+        self.pair(self.company_a, self.company_b, "100.00")
+        ledger_events.reconcile_bank_events(self.connection, actor=self.admin)
+        event_id = self.ledger_events()[0]["id"]
+        confirm(self.connection, event_id, self.company_a, "receivable", "k-none",
+                self.admin)
+        other = positions.list_events(
+            self.connection, from_="2026-01-01", cutoff="2026-07-31",
+            subject="other_receivable",
+        )
+        self.assertEqual([], other["items"])
+
     def test_pagination_is_stable_and_complete(self) -> None:
         for index in range(7):
             at = f"2026-01-{(index % 28) + 1:02d}T10:00:00"