fix(email): add tests for email character escaping

tests/sentry/utils/email/test_message_builder.py

@@ -1,8 +1,12 @@
 import functools
+import os
+from copy import deepcopy
 from unittest.mock import patch
 
+from django.conf import settings
 from django.core import mail
 from django.core.mail.message import EmailMultiAlternatives
+from django.test import override_settings
 
 from sentry import options
 from sentry.models.groupemailthread import GroupEmailThread
@@ -18,6 +22,14 @@
 
 
 class MessageBuilderTest(TestCase):
+    def _override_templates(self):
+        templates = deepcopy(settings.TEMPLATES)
+        for template in templates:
+            template["DIRS"] = [os.path.abspath(os.path.dirname(__file__)) + "/testdata/templates"]
+            template["APP_DIRS"] = False
+
+        return override_settings(TEMPLATES=templates)
+
     def test_raw_content(self):
         msg = MessageBuilder(
             subject="Test",
@@ -333,3 +345,16 @@ def test_adds_type_to_headers(self):
 
         json_xsmtpapi_data = json.loads(out.extra_headers["X-SMTPAPI"])
         assert json_xsmtpapi_data["category"] == "test_email.type"
+
+    def test_doesnt_escape_plaintext(self):
+        context = {"name": "Bob's Hardware & Paint <LTD>"}
+        with self._override_templates():
+            msg = MessageBuilder(
+                subject="Congratulations! You won!",
+                template="escaping_plaintext_test.txt",
+                context=context,
+            )
+            msg.send(["[email protected]"])
+
+        assert len(mail.outbox) == 1
+        assert context["name"] in mail.outbox[0].body

tests/sentry/utils/email/testdata/templates/escaping_plaintext_test.txt

@@ -0,0 +1 @@
+You're our winner, {{ name }}! Congratulations!