stock_account_usability: add shortcut to stock.valuation.layer from product form view

stock_account_usability/models/product.py

@@ -0,0 +1,38 @@
+# Copyright 2022 Akretion France (http://www.akretion.com/)
+# @author: Alexis de Lattre <alexis.delattre@akretion.com>
+# License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl).
+
+from odoo import api, models
+
+
+class ProductTemplate(models.Model):
+    _inherit = 'product.template'
+
+    def action_open_stock_valuation_layer(self):
+        self.ensure_one()
+        ppo = self.env['product.product']
+        if len(self.product_variant_ids) == 1:
+            action = ppo._get_stock_valuation_layer_action(self.product_variant_ids.id)
+        else:
+            action = ppo._get_stock_valuation_layer_action()
+            action["domain"] = [('product_id', 'in', self.product_variant_ids.ids)]
+        return action
+
+
+class ProductProduct(models.Model):
+    _inherit = 'product.product'
+
+    def action_open_stock_valuation_layer(self):
+        self.ensure_one()
+        return self._get_stock_valuation_layer_action(self.id)
+
+    @api.model
+    def _get_stock_valuation_layer_action(self, product_id=None):
+        action = self.env["ir.actions.actions"]._for_xml_id(
+            "stock_account.stock_valuation_layer_action")
+        if product_id:
+            action["context"] = {
+                'search_default_product_id': product_id,
+                'search_default_group_by_product_id': 1,
+                }
+        return action