[FIX] website: delete cow view on module update

Before this commit, when a view was removed during a module update (eg: the
record was deleted from the file), its COW views would not be deleted.

This could lead to unwanted behaviors including tracebacks(1).

This commit is somehow related/an extension of b5fe23055d that handle COW view
write during module update and 2e32cc5aa3 that remove COW views during module
uninstall.

task-1931683

Note: Some existing tests had to be run post install

(1) A view doing a t-call is COW'd, then that view and its t-called view are
    removed. If the cow view is not removed, the t-call will crash (see tests
    in this commit for detailed case).

closes odoo/odoo#31295

Signed-off-by: Jérémy Kersten (jke) <jke@openerp.com>

3 files changed, 81 insertions, 0 deletions

diff --git a/addons/test_website/data/test_website_data.xml b/addons/test_website/data/test_website_data.xml
index df827d542a3..0d829aaab84 100644
--- a/addons/test_website/data/test_website_data.xml
+++ b/addons/test_website/data/test_website_data.xml
@@ -1,6 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <odoo>
     <data noupdate="1">
+
+        <!-- RECORDS FOR RESET VIEWS TESTS -->
         <record id="test_view" model="ir.ui.view">
             <field name="name">Test View</field>
             <field name="type">qweb</field>
@@ -50,5 +52,11 @@
                 <p>placeholder</p>
             </xpath>
         </template>
+
+        <!-- RECORDS FOR MODULE OPERATION TESTS -->
+        <template id="update_module_base_view">
+            <div>I am a base view</div>
+        </template>
+
     </data>
 </odoo>
diff --git a/addons/test_website/tests/__init__.py b/addons/test_website/tests/__init__.py
index 4c32d5f1959..57d8fcd0c25 100644
--- a/addons/test_website/tests/__init__.py
+++ b/addons/test_website/tests/__init__.py
@@ -2,3 +2,4 @@
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
 from . import test_reset_views
+from . import test_views_during_module_operation
diff --git a/addons/test_website/tests/test_views_during_module_operation.py b/addons/test_website/tests/test_views_during_module_operation.py
new file mode 100644
index 00000000000..fceb71b5dc4
--- /dev/null
+++ b/addons/test_website/tests/test_views_during_module_operation.py
@@ -0,0 +1,72 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from odoo.tests import TransactionCase, tagged
+
+
+@tagged('-at_install', 'post_install')
+class TestViewsDuringModuleOperation(TransactionCase):
+    def test_01_cow_views_unlink_on_module_update(self):
+        """ Ensure COW views are correctly removed during module update.
+        Not removing the view could lead to traceback:
+        - Having a view A
+        - Having a view B that inherits from a view C
+        - View B t-call view A
+        - COW view B
+        - Delete view A and B from module datas and update it
+        - Rendering view C will crash since it will render child view B that
+          t-call unexisting view A
+        """
+
+        View = self.env['ir.ui.view']
+        Imd = self.env['ir.model.data']
+
+        update_module_base_view = self.env.ref('test_website.update_module_base_view')
+        update_module_view_to_be_t_called = View.create({
+            'name': 'View to be t-called',
+            'type': 'qweb',
+            'arch': '<div>I will be t-called</div>',
+            'key': 'test_website.update_module_view_to_be_t_called',
+        })
+        update_module_child_view = View.create({
+            'name': 'Child View',
+            'mode': 'extension',
+            'inherit_id': update_module_base_view.id,
+            'arch': '''
+                <div position="inside">
+                    <t t-call="test_website.update_module_view_to_be_t_called"/>
+                </div>
+            ''',
+            'key': 'test_website.update_module_child_view',
+        })
+
+        # Create IMD so when updating the module the views will be removed (not found in file)
+        Imd.create({
+            'module': 'test_website',
+            'name': 'update_module_view_to_be_t_called',
+            'model': 'ir.ui.view',
+            'res_id': update_module_view_to_be_t_called.id,
+        })
+        Imd.create({
+            'module': 'test_website',
+            'name': 'update_module_child_view',
+            'model': 'ir.ui.view',
+            'res_id': update_module_child_view.id,
+        })
+
+        # Trigger COW on child view
+        update_module_child_view.with_context(website_id=1).write({'name': 'Child View (W1)'})
+
+        # Ensure views are correctly setup
+        self.assertEquals(View.search_count([('type', '=', 'qweb'), ('key', '=', update_module_child_view.key)]), 2)
+        self.assertTrue(self.env.ref(update_module_view_to_be_t_called.key))
+        self.assertTrue(self.env.ref(update_module_base_view.key))
+
+        # Uninstall module
+        test_website_module = self.env['ir.module.module'].search([('name', '=', 'test_website')])
+        test_website_module.button_immediate_upgrade()
+
+        # Ensure generic views got removed
+        self.assertFalse(self.env.ref('test_website.update_module_view_to_be_t_called', raise_if_not_found=False))
+        # Ensure specific COW views got removed
+        self.assertEquals(View.search_count([('type', '=', 'qweb'), ('key', '=', 'test_website.update_module_child_view')]), 0)