[IMP] product_category_tax: set tax performance on large recordsets

1) database searching is much more efficient than py filtering
2) writing on multiple products at once is more efficient

product_category_tax/models/product_category.py

@@ -32,7 +32,12 @@ class ProductCategory(models.Model):
     )
 
     def update_product_taxes(self):
-        for template in self.product_template_ids.filtered(
-            lambda p: p.taxes_updeatable_from_category
-        ):
-            template.set_tax_from_category()
+        products = self.env["product.template"].search(
+            [
+                ("categ_id", "in", self.ids),
+                ("taxes_updeatable_from_category", "=", True),
+            ]
+        )
+        if not products:
+            return True
+        return products.set_tax_from_category()

product_category_tax/models/product_product.py

@@ -13,6 +13,4 @@ class ProductProduct(models.Model):
             self.set_tax_from_category()
 
     def set_tax_from_category(self):
-        self.ensure_one()
-        self.taxes_id = [(6, 0, self.categ_id.taxes_id.ids)]
-        self.supplier_taxes_id = [(6, 0, self.categ_id.supplier_taxes_id.ids)]
+        return self.product_tmpl_id.set_tax_from_category()

product_category_tax/models/product_template.py

@@ -1,6 +1,8 @@
 # Copyright 2020 ForgeFlow S.L. (https://www.forgeflow.com)
 # License LGPL-3.0 or later (http://www.gnu.org/licenses/lgpl.html).
 
+from collections import defaultdict
+
 from odoo import api, fields, models
 
 
@@ -15,6 +17,14 @@ class ProductTemplate(models.Model):
             self.set_tax_from_category()
 
     def set_tax_from_category(self):
-        self.ensure_one()
-        self.taxes_id = [(6, 0, self.categ_id.taxes_id.ids)]
-        self.supplier_taxes_id = [(6, 0, self.categ_id.supplier_taxes_id.ids)]
+        records_by_categ = defaultdict(lambda: self.browse())
+        for rec in self:
+            records_by_categ[rec.categ_id] += rec
+        for categ, records in records_by_categ.items():
+            records.write(
+                {
+                    "taxes_id": [(6, 0, categ.taxes_id.ids)],
+                    "supplier_taxes_id": [(6, 0, categ.supplier_taxes_id.ids)],
+                }
+            )
+        return True