feat: add debug validation for product_id in stock.quant and remove redundant comments in stock.location

models/stock_location.py

@@ -1,9 +1,38 @@
 import logging
+import inspect
 from odoo import api, fields, models, _
+from odoo.exceptions import UserError
 from odoo.osv import expression
 
 _logger = logging.getLogger(__name__)
 
+class StockQuant(models.Model):
+    _inherit = 'stock.quant'
+
+    @api.model_create_multi
+    def create(self, vals_list):
+        for vals in vals_list:
+            if not vals.get('product_id'):
+                # Capture the calling stack to see who is trying to create a product-less quant
+                stack = "\n".join([str(s.filename.split('/')[-1]) + " line " + str(s.lineno) for s in inspect.stack()[:10]])
+                _logger.error(f"DEBUG_RESTRICT: STOCK.QUANT CREATE with NO product_id! STACK:\n{stack}")
+                # Force visibility in browser
+                raise UserError(_(
+                    "DEBUG_TRACEBACK: Detected STOCK.QUANT creation with no product_id.\n\n"
+                    "Top calling files:\n%s"
+                ) % stack)
+        return super().create(vals_list)
+
+    def write(self, vals):
+        if 'product_id' in vals and not vals.get('product_id'):
+            stack = "\n".join([str(s.filename.split('/')[-1]) + " line " + str(s.lineno) for s in inspect.stack()[:10]])
+            _logger.error(f"DEBUG_RESTRICT: STOCK.QUANT WRITE with NO product_id! STACK:\n{stack}")
+            raise UserError(_(
+                "DEBUG_TRACEBACK: Detected STOCK.QUANT write with no product_id.\n\n"
+                "Top calling files:\n%s"
+            ) % stack)
+        return super().write(vals)
+
 class StockLocation(models.Model):
     _inherit = 'stock.location'
 
@@ -11,7 +40,6 @@ class StockLocation(models.Model):
     def get_allowed_locations_for_mo(self, mo_id=None, picking_type_id=None):
         """
         Public helper for JS to fetch allowed locations. 
-        Renamed to be public (no leading underscore) for Odoo 19 RPC accessibility.
         """
         allowed_ids = []
         source_name = "None"
@@ -35,7 +63,6 @@ class StockLocation(models.Model):
                     source_name = f"PT {pt.display_name} (M21)"
 
         if allowed_ids:
-            # log as ERROR to ensure it appears in the remote server console regardless of level settings
             _logger.error(f"DEBUG_RESTRICT: Identified {len(allowed_ids)} Allowed Locations for {source_name}: {allowed_ids}")
             return allowed_ids
 
@@ -62,7 +89,6 @@ class StockLot(models.Model):
 
     @api.model
     def web_search_read(self, domain, specification, offset=0, limit=None, order=None, count_limit=None):
-        # We KEEP the Lot search override for the search catalogs as well.
         ctx = self.env.context
         if not ctx.get('skip_location_restriction') and ctx.get('uid'):
             mo_id = (ctx.get('active_mo_id') or ctx.get('default_production_id') or ctx.get('production_id'))