refactor(stock): address layering/robustness review findings (#8, #9, #10)

#8 ledger_preview: wrap the submit-in-memory dry run in a savepoint inside
get_accounting_ledger_preview / get_stock_ledger_preview and roll back to it in a
finally, so the preview never persists entries regardless of caller (previously
only the whitelisted show_*_preview wrappers' full rollback made it safe).

#9 exceptions: move BatchExpiredError and the QualityInspection* errors into a new
erpnext/stock/exceptions.py and re-export them from stock_controller for backward
compatibility (job_card and tests still import from the controller; identity is
preserved). Services now import from the neutral module instead of back from the
controller they were extracted out of.

#10 quality inspection: extract the duplicated doctype->inspection-field map into a
single INSPECTION_FIELDNAME_MAP constant in the service, consumed by both
validate_inspection and check_item_quality_inspection.

Verified: ledger snapshots, quality inspection suite, stock_entry batch-expiry test
stay green; preview smoke-tested to persist nothing and not roll back the caller.

erpnext/controllers/stock_controller.py

@@ -23,25 +23,17 @@ from erpnext.setup.doctype.brand.brand import get_brand_defaults
 from erpnext.setup.doctype.item_group.item_group import get_item_group_defaults
 from erpnext.stock import get_warehouse_account_map
 from erpnext.stock.doctype.item.item import get_item_defaults
+
+# Re-exported for backward compatibility; canonical home is erpnext.stock.exceptions.
+from erpnext.stock.exceptions import (
+	BatchExpiredError,
+	QualityInspectionNotSubmittedError,
+	QualityInspectionRejectedError,
+	QualityInspectionRequiredError,
+)
 from erpnext.stock.stock_ledger import get_items_to_be_repost
 
 
-class QualityInspectionRequiredError(frappe.ValidationError):
-	pass
-
-
-class QualityInspectionRejectedError(frappe.ValidationError):
-	pass
-
-
-class QualityInspectionNotSubmittedError(frappe.ValidationError):
-	pass
-
-
-class BatchExpiredError(frappe.ValidationError):
-	pass
-
-
 class StockController(AccountsController):
 	def validate(self):
 		super().validate()
@@ -674,18 +666,12 @@ def repost_required_for_queue(doc: StockController) -> bool:
 
 @frappe.whitelist()
 def check_item_quality_inspection(doctype: str, docstatus: str | int, items: str | list[dict]):
+	from erpnext.stock.services.quality_inspection import INSPECTION_FIELDNAME_MAP
+
 	if isinstance(items, str):
 		items = json.loads(items)
 
-	inspection_fieldname_map = {
-		"Purchase Receipt": "inspection_required_before_purchase",
-		"Purchase Invoice": "inspection_required_before_purchase",
-		"Subcontracting Receipt": "inspection_required_before_purchase",
-		"Sales Invoice": "inspection_required_before_delivery",
-		"Delivery Note": "inspection_required_before_delivery",
-	}
-
-	inspection_fieldname = inspection_fieldname_map.get(doctype)
+	inspection_fieldname = INSPECTION_FIELDNAME_MAP.get(doctype)
 	if inspection_fieldname is None:
 		return []
 

erpnext/stock/exceptions.py

@@ -0,0 +1,27 @@
+# Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
+# License: GNU General Public License v3. See license.txt
+
+"""Shared exceptions for stock transactions.
+
+Raised by the stock services (serial/batch bundle, quality inspection) and
+re-exported from ``stock_controller`` for backward compatibility, so the services
+do not have to import back from the controller they were extracted out of.
+"""
+
+import frappe
+
+
+class QualityInspectionRequiredError(frappe.ValidationError):
+	pass
+
+
+class QualityInspectionRejectedError(frappe.ValidationError):
+	pass
+
+
+class QualityInspectionNotSubmittedError(frappe.ValidationError):
+	pass
+
+
+class BatchExpiredError(frappe.ValidationError):
+	pass

erpnext/stock/services/ledger_preview.py

@@ -30,17 +30,23 @@ def get_accounting_ledger_preview(doc, filters):
 		"against_voucher",
 	]
 
-	doc.docstatus = 1
+	# Dry run: submit in memory to materialise GL entries, read them, then roll back
+	# to the savepoint so the preview never persists anything, regardless of caller.
+	frappe.db.savepoint("ledger_preview")
+	try:
+		doc.docstatus = 1
 
-	if doc.get("update_stock") or doc.doctype in ("Purchase Receipt", "Delivery Note", "Stock Entry"):
-		doc.update_stock_ledger()
+		if doc.get("update_stock") or doc.doctype in ("Purchase Receipt", "Delivery Note", "Stock Entry"):
+			doc.update_stock_ledger()
 
-	doc.make_gl_entries()
-	columns = get_gl_columns(filters)
-	gl_entries = get_gl_entries_for_preview(doc.doctype, doc.name, fields)
+		doc.make_gl_entries()
+		columns = get_gl_columns(filters)
+		gl_entries = get_gl_entries_for_preview(doc.doctype, doc.name, fields)
 
-	gl_columns = get_columns(columns, fields)
-	gl_data = get_data(fields, gl_entries)
+		gl_columns = get_columns(columns, fields)
+		gl_data = get_data(fields, gl_entries)
+	finally:
+		frappe.db.rollback(save_point="ledger_preview")
 
 	return gl_columns, gl_data
 
@@ -74,15 +80,21 @@ def get_stock_ledger_preview(doc, filters):
 	]
 
 	if doc.get("update_stock") or doc.doctype in ("Purchase Receipt", "Delivery Note", "Stock Entry"):
-		doc.docstatus = 1
-		doc.make_bundle_using_old_serial_batch_fields()
-		doc.update_stock_ledger()
+		# Dry run: submit in memory to materialise SLEs, read them, then roll back to
+		# the savepoint so the preview never persists anything, regardless of caller.
+		frappe.db.savepoint("ledger_preview")
+		try:
+			doc.docstatus = 1
+			doc.make_bundle_using_old_serial_batch_fields()
+			doc.update_stock_ledger()
 
-		columns = get_sl_columns(filters)
-		sl_entries = get_sl_entries_for_preview(doc.doctype, doc.name, fields)
+			columns = get_sl_columns(filters)
+			sl_entries = get_sl_entries_for_preview(doc.doctype, doc.name, fields)
 
-		sl_columns = get_columns(columns, columns_fields)
-		sl_data = get_data(columns_fields, sl_entries)
+			sl_columns = get_columns(columns, columns_fields)
+			sl_data = get_data(columns_fields, sl_entries)
+		finally:
+			frappe.db.rollback(save_point="ledger_preview")
 
 	return sl_columns, sl_data
 

erpnext/stock/services/quality_inspection.py

@@ -10,6 +10,22 @@ inspection have a present / submitted / non-rejected Quality Inspection.
 import frappe
 from frappe import _
 
+from erpnext.stock.exceptions import (
+	QualityInspectionNotSubmittedError,
+	QualityInspectionRejectedError,
+	QualityInspectionRequiredError,
+)
+
+# Doctype -> the document-level "inspection required" flag. Shared with
+# check_item_quality_inspection in stock_controller so the two stay in sync.
+INSPECTION_FIELDNAME_MAP = {
+	"Purchase Receipt": "inspection_required_before_purchase",
+	"Purchase Invoice": "inspection_required_before_purchase",
+	"Subcontracting Receipt": "inspection_required_before_purchase",
+	"Sales Invoice": "inspection_required_before_delivery",
+	"Delivery Note": "inspection_required_before_delivery",
+}
+
 
 class QualityInspectionService:
 	def __init__(self, doc) -> None:
@@ -17,14 +33,7 @@ class QualityInspectionService:
 
 	def validate_inspection(self):
 		"""Checks if quality inspection is set/ is valid for Items that require inspection."""
-		inspection_fieldname_map = {
-			"Purchase Receipt": "inspection_required_before_purchase",
-			"Purchase Invoice": "inspection_required_before_purchase",
-			"Subcontracting Receipt": "inspection_required_before_purchase",
-			"Sales Invoice": "inspection_required_before_delivery",
-			"Delivery Note": "inspection_required_before_delivery",
-		}
-		inspection_required_fieldname = inspection_fieldname_map.get(self.doc.doctype)
+		inspection_required_fieldname = INSPECTION_FIELDNAME_MAP.get(self.doc.doctype)
 
 		# return if inspection is not required on document level
 		if (
@@ -64,8 +73,6 @@ class QualityInspectionService:
 
 	def validate_qi_presence(self, row):
 		"""Check if QI is present on row level. Warn on save and stop on submit if missing."""
-		from erpnext.controllers.stock_controller import QualityInspectionRequiredError
-
 		if not row.quality_inspection:
 			msg = _("Row #{0}: Quality Inspection is required for Item {1}").format(
 				row.idx, frappe.bold(row.item_code)
@@ -77,8 +84,6 @@ class QualityInspectionService:
 
 	def validate_qi_submission(self, row):
 		"""Check if QI is submitted on row level, during submission"""
-		from erpnext.controllers.stock_controller import QualityInspectionNotSubmittedError
-
 		action = frappe.get_single_value("Stock Settings", "action_if_quality_inspection_is_not_submitted")
 		qa_docstatus = frappe.db.get_value("Quality Inspection", row.quality_inspection, "docstatus")
 
@@ -94,8 +99,6 @@ class QualityInspectionService:
 
 	def validate_qi_rejection(self, row):
 		"""Check if QI is rejected on row level, during submission"""
-		from erpnext.controllers.stock_controller import QualityInspectionRejectedError
-
 		action = frappe.get_single_value("Stock Settings", "action_if_quality_inspection_is_rejected")
 		qa_status = frappe.db.get_value("Quality Inspection", row.quality_inspection, "status")
 

erpnext/stock/services/serial_batch_bundle.py

@@ -102,8 +102,8 @@ class SerialBatchBundleService:
 				)
 
 	def validate_serialized_batch(self):
-		from erpnext.controllers.stock_controller import BatchExpiredError
 		from erpnext.stock.doctype.serial_no.serial_no import get_serial_nos
+		from erpnext.stock.exceptions import BatchExpiredError
 
 		is_material_issue = False
 		if self.doc.doctype == "Stock Entry" and self.doc.purpose in ["Material Issue", "Material Transfer"]: