From 28d6468bc495d57a951991ad44061d70e012780b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Thibault=20Delavall=C3=A9e?= <tde@odoo.com>
Date: Mon, 28 Jun 2021 13:38:51 +0000
Subject: [PATCH] [FIX] tools: better support 'almost empty' content from
 editor

It seems quite easy to have a void content in the currently new editor
that actually holds a lot of undesired information, notably a font
tag. This is annoying when having behavior based on an html field
being empty or not. In this commit we therefore improve definition
of an 'empty' html field.

Task ID-2532529
PR odoo/odoo#71793
---
 odoo/addons/base/tests/test_mail.py | 16 ++++++++++++----
 odoo/tools/mail.py                  |  2 +-
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/odoo/addons/base/tests/test_mail.py b/odoo/addons/base/tests/test_mail.py
index 755b959f573..4913558bc60 100644
--- a/odoo/addons/base/tests/test_mail.py
+++ b/odoo/addons/base/tests/test_mail.py
@@ -328,13 +328,21 @@ class TestHtmlTools(BaseCase):
         for content in void_strings_samples:
             self.assertTrue(is_html_empty(content))
 
-        void_html_samples = ['<p><br></p>', '<p><br> </p>', '<p><br /></p >', '<p style="margin: 4px"></p>',
-                             '<div style="margin: 4px"></div>', '<p class="oe_testing"><br></p>']
+        void_html_samples = [
+            '<p><br></p>', '<p><br> </p>', '<p><br /></p >',
+            '<p style="margin: 4px"></p>',
+            '<div style="margin: 4px"></div>',
+            '<p class="oe_testing"><br></p>',
+            '<p><span style="font-weight: bolder;"><font style="color: rgb(255, 0, 0);" class=" "></font></span><br></p>',
+        ]
         for content in void_html_samples:
             self.assertTrue(is_html_empty(content), 'Failed with %s' % content)
 
-        valid_html_samples = ['<p><br>1</p>', '<p>1<br > </p>', '<p style="margin: 4px">Hello World</p>',
-                              '<div style="margin: 4px"><p>Hello World</p></div>']
+        valid_html_samples = [
+            '<p><br>1</p>', '<p>1<br > </p>', '<p style="margin: 4px">Hello World</p>',
+            '<div style="margin: 4px"><p>Hello World</p></div>',
+            '<p><span style="font-weight: bolder;"><font style="color: rgb(255, 0, 0);" class=" ">W</font></span><br></p>',
+        ]
         for content in valid_html_samples:
             self.assertFalse(is_html_empty(content))
 
diff --git a/odoo/tools/mail.py b/odoo/tools/mail.py
index 792bb1e876b..ecda726a23f 100644
--- a/odoo/tools/mail.py
+++ b/odoo/tools/mail.py
@@ -280,7 +280,7 @@ def is_html_empty(html_content):
     """
     if not html_content:
         return True
-    tag_re = re.compile(r'\<\s*\/?(?:p|div|span|br|b|i)(?:(?=\s+\w*)[^/>]*|\s*)/?\s*\>')
+    tag_re = re.compile(r'\<\s*\/?(?:p|div|span|br|b|i|font)(?:(?=\s+\w*)[^/>]*|\s*)/?\s*\>')
     return not bool(re.sub(tag_re, '', html_content).strip())