[FIX] mail: stop squashing message if the previous message is deleted

closes odoo/odoo#77922

X-original-commit: 92c7f11e3c3cc70a3d520f0977f474e55dc7bced
Signed-off-by: Sébastien Theys (seb) <seb@odoo.com>

addons/mail/static/src/components/delete_message_confirm_dialog/delete_message_confirm_dialog.xml

@@ -1,15 +1,17 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <templates xml:space="preserve">
     <t t-name="mail.DeleteMessageConfirmDialog" owl="1">
-        <Dialog contentClass="'o_DeleteMessageConfirmDialog'" title="title" t-on-dialog-closed="messageActionList.onDeleteConfirmDialogClosed" t-ref="dialog">
-            <p>Are you sure you want to delete this message?</p>
-            <blockquote class="o_DeleteMessageConfirmDialog_blockquote">
-                <Message messageViewLocalId="messageActionList.messageViewForDelete.localId"/>
-            </blockquote>
-            <small t-if="!messageActionList.message.originThread or messageActionList.message.originThread.model !== 'mail.channel'">Pay attention: The followers of this document who were notified by email will still be able to read the content of this message and reply to it.</small>
-            <t t-set-slot="buttons">
-                <button class="btn btn-primary" t-on-click="messageActionList.onClickConfirmDelete">Delete</button>
-                <button class="btn btn-secondary" t-on-click="dialogRef.comp._close()">Cancel</button>
+        <Dialog contentClass="'o_DeleteMessageConfirmDialog'" title="title" t-on-dialog-closed="messageActionList and messageActionList.onDeleteConfirmDialogClosed" t-ref="dialog">
+            <t t-if="messageActionList">
+                <p>Are you sure you want to delete this message?</p>
+                <blockquote class="o_DeleteMessageConfirmDialog_blockquote">
+                    <Message messageViewLocalId="messageActionList.messageViewForDelete.localId"/>
+                </blockquote>
+                <small t-if="!messageActionList.message.originThread or messageActionList.message.originThread.model !== 'mail.channel'">Pay attention: The followers of this document who were notified by email will still be able to read the content of this message and reply to it.</small>
+                <t t-set-slot="buttons">
+                    <button class="btn btn-primary" t-on-click="messageActionList.onClickConfirmDelete">Delete</button>
+                    <button class="btn btn-secondary" t-on-click="dialogRef.comp._close()">Cancel</button>
+                </t>
             </t>
         </Dialog>
     </t>

addons/mail/static/src/components/message_list/message_list.xml

@@ -5,7 +5,7 @@
         <div class="o_MessageList" t-att-class="{ 'o-empty': threadView and threadView.messages.length === 0 }" t-on-scroll="onScroll">
             <t t-if="threadView">
                 <!-- No result messages -->
-                <t t-if="threadView.nonEmptyMessages.length === 0">
+                <t t-if="threadView.threadCache.orderedNonEmptyMessages.length === 0">
                     <div class="o_MessageList_empty o_MessageList_item">
                         <t t-if="threadView.thread === messaging.inbox">
                             <div class="o_MessageList_emptyTitle">
@@ -41,10 +41,10 @@
                         </button>
                     </div>
                 </t>
-                <t t-elif="threadView.order === 'asc' and threadView.messageViews.length > 0">
+                <t t-if="!threadView.threadCache.hasLoadingFailed and threadView.order === 'asc'">
                     <t t-call="mail.MessageList.loadMore"/>
                 </t>
-                <div t-if="threadView.order === 'asc' and threadView.nonEmptyMessages.length !== 0 and !(threadView and threadView.thread and threadView.thread.model === 'mail.box')" class="flex-grow-1"/>
+                <div t-if="threadView.order === 'asc' and threadView.threadCache.orderedNonEmptyMessages.length !== 0 and !(threadView and threadView.thread and threadView.thread.model === 'mail.box')" class="flex-grow-1"/>
                 <!-- MESSAGES -->
                 <t t-set="current_day" t-value="0"/>
                 <t t-foreach="threadView.messageViews" t-as="messageView" t-key="messageView.localId">
@@ -65,7 +65,7 @@
                     </t>
                 </t>
                 <!-- LOADING (if order desc)-->
-                <t t-if="!threadView.threadCache.hasLoadingFailed and threadView.order === 'desc' and threadView.messageViews.length > 0">
+                <t t-if="!threadView.threadCache.hasLoadingFailed and threadView.order === 'desc'">
                     <t t-call="mail.MessageList.loadMore"/>
                 </t>
             </t>

addons/mail/static/src/models/thread_cache/thread_cache.js

@@ -138,15 +138,6 @@ function factory(dependencies) {
             return replace(this.fetchedMessages.concat(newerMessages));
         }
 
-        /**
-         *
-         * @private
-         * @returns {mail.message[]}
-         */
-        _computeNonEmptyMessages() {
-            return replace(this.messages.filter(message => !message.isEmpty));
-        }
-
         /**
          * @private
          * @returns {mail.message[]}
@@ -163,6 +154,15 @@ function factory(dependencies) {
             return replace(this.messages.sort((m1, m2) => m1.id < m2.id ? -1 : 1));
         }
 
+        /**
+         *
+         * @private
+         * @returns {mail.message[]}
+         */
+        _computeOrderedNonEmptyMessages() {
+            return replace(this.orderedMessages.filter(message => !message.isEmpty));
+        }
+
         /**
          * @private
          * @returns {boolean}
@@ -402,12 +402,6 @@ function factory(dependencies) {
         messages: many2many('mail.message', {
             compute: '_computeMessages',
         }),
-        /**
-         * List of non empty messages linked to this cache.
-         */
-        nonEmptyMessages: many2many('mail.message', {
-            compute: '_computeNonEmptyMessages',
-        }),
         /**
          * Ordered list of messages that have been fetched by this cache.
          *
@@ -424,6 +418,12 @@ function factory(dependencies) {
         orderedMessages: many2many('mail.message', {
             compute: '_computeOrderedMessages',
         }),
+        /**
+         * List of ordered non empty messages linked to this cache.
+         */
+        orderedNonEmptyMessages: many2many('mail.message', {
+            compute: '_computeOrderedNonEmptyMessages',
+        }),
         thread: one2one('mail.thread', {
             inverse: 'cache',
             readonly: true,

addons/mail/static/src/models/thread_view/thread_view.js

@@ -140,7 +140,7 @@ function factory(dependencies) {
             if (!this.threadCache) {
                 return clear();
             }
-            const orderedMessages = this.threadCache.orderedMessages;
+            const orderedMessages = this.threadCache.orderedNonEmptyMessages;
             if (this.order === 'desc') {
                 orderedMessages.reverse();
             }
@@ -478,9 +478,6 @@ function factory(dependencies) {
             inverse: 'threadView',
             isCausal: true,
         }),
-        nonEmptyMessages: many2many('mail.message', {
-            related: 'threadCache.nonEmptyMessages',
-        }),
         /**
          * States the order mode of the messages on this thread view.
          * Either 'asc', or 'desc'.