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

src/bank_importer/subjects.py

@@ -209,36 +209,42 @@ def confirm_subject(
         raise SubjectInputError("必须填写科目确认依据。")
     if subject_code not in SUBJECTS:
         raise SubjectInputError("科目必须是应收/应付/其他应收/其他应付之一。")
-    subject_code = subject_code
-
-    if request_key:
-        existing = connection.execute(
-            """
-            SELECT * FROM ledger_event_revisions
-            WHERE ledger_event_id = ? AND idempotency_key = ?
-            ORDER BY id LIMIT 1
-            """,
-            (ledger_event_id, request_key),
-        ).fetchone()
-        if existing is not None:
-            return _revision_payload(connection, existing)
-
-    current = current_revision(connection, ledger_event_id)
-    if current is None:
-        raise SubjectConflictError("该事件不存在或没有当前修订。")
-    if current["state"] != "pending_subject":
-        raise SubjectConflictError("只有待确认科目的事件可以确认科目。")
-    if expected_revision is not None and int(expected_revision) != current["revision"]:
-        raise SubjectConflictError("事件已发生变更，请刷新后重试。")
-    participants = {current["payer_company_id"], current["payee_company_id"]}
-    if perspective_company_id not in participants:
-        raise SubjectInputError("视角公司必须是事件参与方。")
 
     began = False
     if not connection.in_transaction:
         connection.execute("BEGIN IMMEDIATE")
         began = True
     try:
+        if request_key:
+            existing = connection.execute(
+                """
+                SELECT * FROM ledger_event_revisions
+                WHERE ledger_event_id = ? AND idempotency_key = ?
+                ORDER BY id LIMIT 1
+                """,
+                (ledger_event_id, request_key),
+            ).fetchone()
+            if existing is not None:
+                if began:
+                    connection.commit()
+                return _revision_payload(connection, existing)
+
+        current = current_revision(connection, ledger_event_id)
+        if current is None:
+            raise SubjectConflictError("该事件不存在或没有当前修订。")
+        if current["state"] != "pending_subject":
+            raise SubjectConflictError("只有待确认科目的事件可以确认科目。")
+        # ``expected_revision`` may be the revision row id (what the API/UI
+        # sends as ``ledger_revision_id``) or the per-event sequence number;
+        # both identify the exact revision the client saw.
+        if expected_revision is not None and int(expected_revision) not in (
+            current["id"], current["revision"],
+        ):
+            raise SubjectConflictError("事件已发生变更，请刷新后重试。")
+        participants = {current["payer_company_id"], current["payee_company_id"]}
+        if perspective_company_id not in participants:
+            raise SubjectInputError("视角公司必须是事件参与方。")
+
         revision_id = append_revision(
             connection,
             ledger_event_id,