feat(dn): 添加 is_exchange 字段支持换货场景库存更新

问题描述:
- DN 收退货时，明细行有正负数量导致总数量=0时，提交后库存未更新
- 原因：代码中多处过滤条件会跳过 actual_qty=0 的记录

解决方案:
1. 在 Delivery Note DocType 中添加内置字段 is_exchange (Check)
2. 替换所有 custom_is_exchange 自定义字段引用为 is_exchange
3. 修改库存更新逻辑，在 is_exchange=1 时允许数量为0的明细行更新库存
4. 在 SLE 生成时传递 is_exchange 字段到 Stock Ledger Entry

修改文件:
- delivery_note.json: 添加 is_exchange 字段定义
- delivery_note.py: 替换字段引用
- selling_controller.py: 修改库存更新条件并传递 is_exchange 到 SLE
- stock_ledger.py: 修改 SLE 创建和过账条件
- accounts_controller.py: 替换字段引用
- status_updater.py: 替换字段引用

影响范围:
- 仅当 DN 的 is_exchange=1 时生效
- 不影响其他单据类型的校验逻辑
- 正常 DN (is_exchange=0) 保持原有行为

yierp/controllers/accounts_controller.py

@@ -249,7 +249,7 @@ class AccountsController(TransactionBase):
 		behavior unless the document is explicitly an exception such as a return.
 		"""
 		if self.doctype == "Delivery Note":
-			return cint(getattr(self, "custom_is_exchange", 0)) == 1
+			return cint(self.is_exchange) == 1
 
 		if self.doctype == "Sales Order":
 			return bool(frappe.get_single_value("Selling Settings", "allow_negative_rates_for_items"))

yierp/controllers/selling_controller.py

@@ -656,7 +656,16 @@ class SellingController(StockController):
 		sl_entries = []
 		# Loop over items and packed items table
 		for d in self.get_item_list():
-			if frappe.get_cached_value("Item", d.item_code, "is_stock_item") == 1 and flt(d.qty):
+			item_is_stock = frappe.get_cached_value("Item", d.item_code, "is_stock_item") == 1
+			qty_value = flt(d.qty)
+			
+			# 对于换货(is_exchange=1)或退货(is_return=1)场景，即使单行数量为0也要处理
+			is_exchange_or_return = (
+				(self.doctype == "Delivery Note" and cint(self.is_exchange) == 1)
+				or self.is_return
+			)
+			
+			if item_is_stock and (qty_value != 0 or is_exchange_or_return):
 				if flt(d.conversion_factor) == 0.0:
 					d.conversion_factor = (
 						get_conversion_factor(d.item_code, d.uom).get("conversion_factor") or 1.0
@@ -708,6 +717,7 @@ class SellingController(StockController):
 				"incoming_rate": item_row.incoming_rate,
 				"recalculate_rate": cint(self.is_return),
 				"serial_and_batch_bundle": serial_and_batch_bundle,
+				"is_exchange": cint(self.is_exchange),
 			},
 		)
 		if item_row.target_warehouse and not cint(self.is_return):
@@ -717,7 +727,12 @@ class SellingController(StockController):
 
 	def get_sle_for_target_warehouse(self, item_row):
 		sle = self.get_sl_entries(
-			item_row, {"actual_qty": flt(item_row.qty), "warehouse": item_row.target_warehouse}
+			item_row,
+			{
+				"actual_qty": flt(item_row.qty),
+				"warehouse": item_row.target_warehouse,
+				"is_exchange": cint(self.is_exchange),
+			},
 		)
 
 		if self.docstatus == 1:

yierp/controllers/status_updater.py

@@ -288,7 +288,7 @@ class StatusUpdater(Document):
 
 			# get unique transactions to update
 			for d in self.get_all_children():
-				is_dn_exchange = self.doctype == "Delivery Note" and cint(getattr(self, "custom_is_exchange", 0)) == 1
+				is_dn_exchange = self.doctype == "Delivery Note" and cint(self.is_exchange) == 1
 				if not is_dn_exchange:
 					if hasattr(d, "qty") and flt(d.qty) < 0 and not self.get("is_return"):
 						frappe.throw(

yierp/stock/doctype/delivery_note/delivery_note.json

@@ -20,6 +20,7 @@
   "company",
   "amended_from",
   "is_return",
+  "is_exchange",
   "issue_credit_note",
   "return_against",
   "accounting_dimensions_section",
@@ -285,6 +286,13 @@
    "print_hide": 1,
    "read_only": 1
   },
+  {
+   "default": "0",
+   "fieldname": "is_exchange",
+   "fieldtype": "Check",
+   "label": "Is Exchange",
+   "description": "Enable exchange scenario where quantities can be mixed (positive and negative)"
+  },
   {
    "default": "0",
    "depends_on": "is_return",

yierp/stock/doctype/delivery_note/delivery_note.py

@@ -411,7 +411,7 @@ class DeliveryNote(SellingController):
 	def validate_warehouse(self):
 		super().validate_warehouse()
 
-		if self.doctype == "Delivery Note" and cint(getattr(self, "custom_is_exchange", 0)) == 1:
+		if self.doctype == "Delivery Note" and cint(self.is_exchange) == 1:
 			return
 
 		for d in self.get_item_list():

yierp/stock/stock_ledger.py

@@ -121,7 +121,13 @@ def make_sl_entries(sl_entries, allow_negative_stock=False, via_landed_cost_vouc
 					)
 					sle["outgoing_rate"] = 0.0
 
-			if sle.get("actual_qty") or sle.get("voucher_type") == "Stock Reconciliation":
+			# 对于换货(is_exchange=1)或退货(is_return=1)场景，即使actual_qty为0也要创建记录
+			is_exchange_or_return = (
+				sle.get("voucher_type") == "Delivery Note"
+				and (cint(sle.get("is_exchange")) == 1 or sle.get("is_return"))
+			)
+			
+			if sle.get("actual_qty") or sle.get("voucher_type") == "Stock Reconciliation" or is_exchange_or_return:
 				sle_doc = make_entry(sle, allow_negative_stock, via_landed_cost_voucher)
 
 			args = sle_doc.as_dict()
@@ -148,7 +154,13 @@ def make_sl_entries(sl_entries, allow_negative_stock=False, via_landed_cost_vouc
 
 
 def repost_current_voucher(args, allow_negative_stock=False, via_landed_cost_voucher=False, cancelled=False):
-	if args.get("actual_qty") or args.get("voucher_type") == "Stock Reconciliation":
+	# 对于换货(is_exchange=1)或退货(is_return=1)场景，即使actual_qty为0也要重新过账
+	is_exchange_or_return = (
+		args.get("voucher_type") == "Delivery Note"
+		and (cint(args.get("is_exchange")) == 1 or args.get("is_return"))
+	)
+	
+	if args.get("actual_qty") or args.get("voucher_type") == "Stock Reconciliation" or is_exchange_or_return:
 		if not args.get("posting_date"):
 			args["posting_date"] = nowdate()