[FIX] web_editor: send the html editor writes one after another

With the following view hierarchy:
   A
   |
   B' (oe_structure_ID view)

Before this fix, when saving multiple templates at once from the same hierarchy
the COW views (website) would not be saved correctly as the first call to
`write` would COW the parent view, then the second concurent call to `write`
would create the child specific view under the generic parent view.
Instead, the generic parent should have been cloned to a specific parent view
and then the child view should be COW under the specific parent.

  A    A'
  |    |
  B'   B*' (This one is the old B', without B' changes in the html editor)

Instead of

  A   A'
      |
      B'

Calling the `write` one after another will do the trick. Indeed, when the
second call is fired, the first call has already triggered the COW behavior.
Thus, the second call correctly retrieves the COW view.

Another issue might still appear, if the parent view write is sent first.
Indeed, the parent view will be COW, thus the specific child view (second write
waiting to be fired) will be deleted to be added on the new specific hierarchy.
Thus, that write will then raise an error since the view does not exist anymore.

task-1934279
Fix odoo#30447

addons/web_editor/static/src/js/widgets/ace.js

@@ -2,6 +2,7 @@ odoo.define('web_editor.ace', function (require) {
 'use strict';
 
 var ajax = require('web.ajax');
+var concurrency = require('web.concurrency');
 var core = require('web.core');
 var Dialog = require('web.Dialog');
 var Widget = require('web.Widget');
@@ -536,6 +537,7 @@ var ViewEditor = Widget.extend({
      *                    error occured.
      */
     _saveResources: function () {
+        var self = this;
         var toSave = {};
         var errorFound = false;
         _.each(this.editingSessions, (function (editingSessions, type) {
@@ -563,8 +565,15 @@ var ViewEditor = Widget.extend({
         if (errorFound) return $.Deferred().reject(errorFound);
 
         var defs = [];
+        var mutex = new concurrency.Mutex();
         _.each(toSave, (function (_toSave, type) {
-            defs = defs.concat(_.map(_toSave, (type === 'xml' ? this._saveView : this._saveSCSS).bind(this)));
+            // Child views first as COW on a parent would delete them
+            _toSave = _.sortBy(_toSave, 'id').reverse();
+            _.each(_toSave, function (session) {
+                defs.push(mutex.exec(function () {
+                    return (type === 'xml' ? self._saveView(session) : self._saveSCSS(session));
+                }));
+            });
         }).bind(this));
 
         return $.when.apply($, defs).fail((function (session, error) {

addons/website/static/src/js/html_editor.test.js

@@ -0,0 +1,75 @@
+odoo.define('website.test.html_editor', function (require) {
+'use strict';
+
+var tour = require('web_tour.tour');
+var base = require('web_editor.base');
+
+tour.register('html_editor_multiple_templates', {
+    test: true,
+    url: '/aboutus',
+    wait_for: base.ready(),
+},
+    [
+        // 1. Edit the page through Edit Mode, it will COW the view
+        {
+            content: "enter edit mode",
+            trigger: 'a[data-action=edit]',
+        },
+        {
+            content: "drop a snippet",
+            trigger: '#oe_snippets .oe_snippet:has(.s_cover) .oe_snippet_thumbnail',
+            // id starting by 'oe_structure..' will actually create an inherited view
+            run: "drag_and_drop #oe_structure_test_ui",
+        },
+        {
+            content: "save the page",
+            extra_trigger: '#wrapwrap .s_cover',
+            trigger: "#web_editor-top-edit button[data-action=save]",
+        },
+        // 2. Edit generic aboutus view
+        {
+            content: "open customize menu",
+            extra_trigger: "body:not(.editor_enable)",
+            trigger: '#customize-menu > a',
+        },
+        {
+            content: "open html editor",
+            trigger: '#html_editor',
+        },
+        {
+            content: "add something in the aboutus view",
+            trigger: 'div.ace_line .ace_xml:contains("aboutus")',
+            run: function () {
+                ace.edit('ace-view-editor').getSession().insert({row: 3, column: 1}, '<p>somenewcontent</p>\n');
+            },
+        },
+        // 3. Edit oe_structure specific view
+        {
+            content: "select oe_structure specific view",
+            trigger: 'div.ace_line .ace_xml:contains("somenewcontent")',
+            run: function () {
+                var viewId = $('#ace-view-list option:contains("oe_structure")').val();
+                $('#ace-view-list').val(viewId).trigger('change');
+            },
+        },
+        {
+            content: "add something in the oe_structure specific view",
+            trigger: 'div.ace_line .ace_xml:contains("s_cover")',
+            run: function () {
+                ace.edit('ace-view-editor').getSession().insert({row: 2, column: 1}, '<p>anothernewcontent</p>\n');
+            },
+        },
+        {
+            content: "save the html editor",
+            extra_trigger: 'div.ace_line .ace_xml:contains("anothernewcontent")',
+            trigger: ".o_ace_view_editor button[data-action=save]",
+        },
+        {
+           content: "check that the page has both modification",
+           extra_trigger: '#wrapwrap:contains("anothernewcontent")',
+           trigger: '#wrapwrap:contains("somenewcontent")',
+           run: function () {}, // it's a check
+       },
+    ]
+);
+});

addons/website/tests/test_ui.py

@@ -4,6 +4,32 @@
 import odoo
 import odoo.tests
 
+
+@odoo.tests.tagged('-at_install', 'post_install')
+class TestUiHtmlEditor(odoo.tests.HttpCase):
+    def test_html_editor_multiple_templates(self):
+        Website = self.env['website']
+        View = self.env['ir.ui.view']
+        generic_aboutus = Website.viewref('website.aboutus')
+        # Use an empty page layout with oe_structure id for this test
+        oe_structure_layout = '''
+            <t name="About us" t-name="website.aboutus">
+                <t t-call="website.layout">
+                    <p>aboutus</p>
+                    <div id="oe_structure_test_ui" class="oe_structure oe_empty"/>
+                </t>
+            </t>
+        '''
+        generic_aboutus.arch = oe_structure_layout
+        self.phantom_js("/", "odoo.__DEBUG__.services['web_tour.tour'].run('html_editor_multiple_templates')", "odoo.__DEBUG__.services['web_tour.tour'].tours.html_editor_multiple_templates.ready", login='admin')
+        self.assertEqual(View.search_count([('key', '=', 'website.aboutus')]), 2, "Aboutus view should have been COW'd")
+        self.assertTrue(generic_aboutus.arch == oe_structure_layout, "Generic Aboutus view should be untouched")
+        self.assertEqual(len(generic_aboutus.inherit_children_ids.filtered(lambda v: 'oe_structure' in v.name)), 0, "oe_structure view should have been deleted when aboutus was COW")
+        specific_aboutus = Website.with_context(website_id=1).viewref('website.aboutus')
+        self.assertTrue(specific_aboutus.arch != oe_structure_layout, "Specific Aboutus view should have been changed")
+        self.assertEqual(len(specific_aboutus.inherit_children_ids.filtered(lambda v: 'oe_structure' in v.name)), 1, "oe_structure view should have been created on the specific tree")
+
+
 class TestUiTranslate(odoo.tests.HttpCase):
     def test_admin_tour_rte_translator(self):
         self.phantom_js("/", "odoo.__DEBUG__.services['web_tour.tour'].run('rte_translator')", "odoo.__DEBUG__.services['web_tour.tour'].tours.rte_translator.ready", login='admin', timeout=120)

addons/website/views/website_templates.xml

@@ -57,6 +57,8 @@
         <script type="text/javascript" src="/website/static/src/js/content/zoomodoo.js"/>
 
         <script type="text/javascript" src="/website/static/src/js/menu/navbar.js"/>
+
+        <script type="text/javascript" src="/website/static/src/js/html_editor.test.js"/>
     </xpath>
 </template>