[FIX] base, web_editor, mail, digest: preserve comments in sent e-mails

For email design in the context of Microsoft Outlook, we want to keep
some magic Microsoft comments (Outlook conditional comment), which -
until this commit - were skipped by QWeb. These allow us to change the
rendering exclusively for Outlook so as to overcome some of its
limitations. This commit introduces a qweb rendering option
(`preserve_comments`) for when - like in mass mailing and digest - we
want to keep comments.

Part-of: odoo/odoo#80621

addons/digest/models/digest.py

@@ -144,7 +144,8 @@ class Digest(models.Model):
                 'tips': self._compute_tips(user.company_id, user, tips_count=tips_count, consumed=consum_tips),
                 'preferences': self._compute_preferences(user.company_id, user),
             },
-            post_process=True
+            post_process=True,
+            options={'preserve_comments': True}
         )[self.id]
         full_mail = self.env['mail.render.mixin']._render_encapsulate(
             'digest.digest_mail_layout',

addons/mail/models/mail_render_mixin.py

@@ -276,8 +276,12 @@ class MailRenderMixin(models.AbstractModel):
         for record in self.env[model].browse(res_ids):
             variables['object'] = record
             try:
-                render_result = self.env['ir.qweb']._render(html.fragment_fromstring(
-                    template_src, create_parent='div'), variables, raise_on_code=is_restricted)
+                render_result = self.env['ir.qweb']._render(
+                    html.fragment_fromstring(template_src, create_parent='div'),
+                    variables,
+                    raise_on_code=is_restricted,
+                    **(options or {})
+                )
                 # remove the rendered tag <div> that was added in order to wrap potentially multiples nodes into one.
                 render_result = render_result[5:-6]
             except QWebCodeFound:
@@ -329,7 +333,7 @@ class MailRenderMixin(models.AbstractModel):
         for record in self.env[model].browse(res_ids):
             variables['object'] = record
             try:
-                render_result = view._render(variables, engine='ir.qweb', minimal_qcontext=True)
+                render_result = view._render(variables, engine='ir.qweb', minimal_qcontext=True, options=options)
             except Exception as e:
                 _logger.info("Failed to render template : %s (%d)", template_src, view.id, exc_info=True)
                 raise UserError(_("Failed to render template : %(xml_id)s (%(view_id)d)",

addons/mail/tests/test_mail_composer.py

@@ -47,14 +47,9 @@ class TestMailComposer(MailCommon):
 
         values = mail_compose_message.get_mail_values(self.partner_employee.ids)
 
-        self.assertIn("""<div>
-    <h1>Hello sir!</h1>
-    <p>Here! <a href="https://www.example.com">
-        A link for you!
-    </a> Make good use of it.</p>
-</div>""",
+        self.assertIn(self.body_html,
             values[self.partner_employee.id]['body_html'],
-            'We must remove comments')
+            'We must preserve (mso) comments in email html')
 
     @users('employee')
     def test_mail_mass_mode_compose_with_mso(self):
@@ -74,11 +69,6 @@ class TestMailComposer(MailCommon):
 
         values = composer.get_mail_values(self.partner_employee.ids)
 
-        self.assertIn("""<div>
-    <h1>Hello sir!</h1>
-    <p>Here! <a href="https://www.example.com">
-        A link for you!
-    </a> Make good use of it.</p>
-</div>""",
+        self.assertIn(self.body_html,
             values[self.partner_employee.id]['body_html'],
-            'We must remove comments')
+            'We must preserve (mso) comments in email html')

addons/mail/wizard/mail_compose_message.py

@@ -598,7 +598,8 @@ class MailComposer(models.TransientModel):
             res_ids = [res_ids]
 
         subjects = self._render_field('subject', res_ids, options={"render_safe": True})
-        bodies = self._render_field('body', res_ids, post_process=True)
+        # We want to preserve comments in emails so as to keep mso conditionals
+        bodies = self._render_field('body', res_ids, post_process=True, options={'preserve_comments': self.composition_mode == 'mass_mail'})
         emails_from = self._render_field('email_from', res_ids)
         replies_to = self._render_field('reply_to', res_ids)
         default_recipients = {}

addons/web_editor/models/ir_ui_view.py

@@ -18,7 +18,7 @@ EDITING_ATTRIBUTES = ['data-oe-model', 'data-oe-id', 'data-oe-field', 'data-oe-x
 class IrUiView(models.Model):
     _inherit = 'ir.ui.view'
 
-    def _render(self, values=None, engine='ir.qweb', minimal_qcontext=False):
+    def _render(self, values=None, engine='ir.qweb', minimal_qcontext=False, options=None):
         if values and values.get('editable'):
             try:
                 self.check_access_rights('write')
@@ -26,7 +26,7 @@ class IrUiView(models.Model):
             except AccessError:
                 values['editable'] = False
 
-        return super(IrUiView, self)._render(values=values, engine=engine, minimal_qcontext=minimal_qcontext)
+        return super(IrUiView, self)._render(values=values, engine=engine, minimal_qcontext=minimal_qcontext, options=options)
 
     #------------------------------------------------------
     # Save from html

odoo/addons/base/models/ir_ui_view.py

@@ -1974,13 +1974,13 @@ actual arch.
     def _render_template(self, template, values=None, engine='ir.qweb'):
         return self.browse(self.get_view_id(template))._render(values, engine)
 
-    def _render(self, values=None, engine='ir.qweb', minimal_qcontext=False):
+    def _render(self, values=None, engine='ir.qweb', minimal_qcontext=False, options=None):
         assert isinstance(self.id, int)
 
         qcontext = dict() if minimal_qcontext else self._prepare_qcontext()
         qcontext.update(values or {})
 
-        return self.env[engine]._render(self.id, qcontext)
+        return self.env[engine]._render(self.id, qcontext, **(options or {}))
 
     @api.model
     def _prepare_qcontext(self):

odoo/addons/base/models/qweb.py

@@ -951,7 +951,10 @@ class QWeb(object):
         body = []
         if el.getchildren():
             for item in el:
-                if not isinstance(item, etree._Comment):
+                if isinstance(item, etree._Comment):
+                    if options.get('preserve_comments'):
+                        self._appendText("<!--%s-->" % item.text, options)
+                else:
                     body.extend(self._compile_node(item, options, indent))
                 # comments can also contains tail text
                 if item.tail is not None: