[ADD] user friendly error handling for restricted qty on ecommerce app

sale_restricted_qty_website_sale/tests/__init__.py

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+from . import test_restricted_qty_website_sale

sale_restricted_qty_website_sale/tests/test_restricted_qty_website_sale.py

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+from lxml import html
+
+from odoo.exceptions import ValidationError
+from odoo.tests import HttpCase, tagged
+
+from odoo.addons.http_routing.models.ir_http import slug
+
+
+@tagged("post_install", "-at_install")
+class TestRestrictedQtyInfo(HttpCase):
+    @classmethod
+    def setUpClass(cls):
+        super().setUpClass()
+        cls.partner = cls.env["res.partner"].create({"name": "eCommerce customer"})
+        cls.product_min = cls._create_product(
+            "Product min 6", manual_sale_min_qty=6.0
+        )
+        cls.product_free = cls._create_product("Unrestricted product")
+        # force = Yes -> purely indicative bound, nothing to tell the customer
+        cls.product_indicative = cls._create_product(
+            "Product min 6 indicative",
+            manual_sale_min_qty=6.0,
+            manual_force_sale_min_qty="force",
+        )
+
+    @classmethod
+    def _create_product(cls, name, **restrictions):
+        values = {
+            "name": name,
+            "type": "consu",
+            "list_price": 10.0,
+            "sale_ok": True,
+            "is_published": True,
+        }
+        values.update(restrictions)
+        return cls.env["product.template"].create(values).product_variant_id
+
+    # ------------------------------------------------------------------
+    # Error message
+    # ------------------------------------------------------------------
+
+    def _create_line(self, product, qty):
+        order = self.env["sale.order"].create({"partner_id": self.partner.id})
+        self.env["sale.order.line"].create(
+            {
+                "order_id": order.id,
+                "product_id": product.id,
+                "product_uom_qty": qty,
+            }
+        )
+        # @api.constrains are evaluated on flush, not on create().
+        self.env.flush_all()
+        return order
+
+    def test_error_message_is_customer_facing(self):
+        with self.assertRaises(ValidationError) as error:
+            self._create_line(self.product_min, 1)
+
+        message = str(error.exception)
+        self.assertIn("Product min 6", message)
+        self.assertIn("6", message)
+        self.assertNotIn("force min", message, "Upstream jargon still present")
+
+    def test_valid_quantity_raises_nothing(self):
+        self._create_line(self.product_min, 6)
+
+    def test_indicative_minimum_still_does_not_block(self):
+        self._create_line(self.product_indicative, 1)
+
+    # ------------------------------------------------------------------
+    # Product page display
+    # ------------------------------------------------------------------
+
+    def _hint_on_page(self, product):
+        response = self.url_open("/shop/%s" % slug(product.product_tmpl_id))
+        self.assertEqual(response.status_code, 200)
+        tree = html.fromstring(response.content)
+        return tree.xpath("//div[contains(@class, 'o_wsale_qty_restriction')]")
+
+    def test_hint_is_displayed(self):
+        hint = self._hint_on_page(self.product_min)
+        self.assertEqual(len(hint), 1)
+        self.assertIn("6", hint[0].text_content())
+
+    def test_no_hint_without_restriction(self):
+        self.assertFalse(self._hint_on_page(self.product_free))
+
+    def test_no_hint_for_an_indicative_minimum(self):
+        self.assertFalse(self._hint_on_page(self.product_indicative))