passes the test

tests/chatmaild/test_filtermail.py

@@ -1,4 +1,4 @@
-from chatmaild.filtermail import check_encrypted, check_DATA, SendRateLimiter
+from chatmaild.filtermail import check_encrypted, check_DATA, SendRateLimiter, check_mdn
 import pytest
 
 
@@ -41,8 +41,33 @@ def test_filtermail_encryption_detection(maildata):
     assert not check_encrypted(msg)
 
 
-def test_filtermail_mdn_is_not_encrypted(maildata):
-    assert not check_encrypted(maildata("mdn.eml"))
+def test_filtermail_is_mdn(maildata, gencreds):
+    from_addr = gencreds()[0]
+    to_addr = gencreds()[0] + ".other"
+    msg = maildata("mdn.eml", from_addr, to_addr)
+
+    class env:
+        mail_from = from_addr
+        rcpt_tos = [to_addr]
+        content = msg.as_bytes()
+
+    assert check_mdn(msg, env)
+    print(msg.as_string())
+    assert not check_DATA(env)
+
+
+def test_filtermail_to_multiple_recipients_no_mdn(maildata, gencreds):
+    from_addr = gencreds()[0]
+    to_addr = gencreds()[0] + ".other"
+    thirdaddr = gencreds()[0]
+    msg = maildata("mdn.eml", from_addr, to_addr)
+
+    class env:
+        mail_from = from_addr
+        rcpt_tos = [to_addr, thirdaddr]
+        content = msg.as_bytes()
+
+    assert not check_mdn(msg, env)
 
 
 def test_send_rate_limiter():

tests/conftest.py

@@ -290,7 +290,7 @@ class Remote:
 def maildata(request, gencreds):
     datadir = conftestdir.joinpath("mail-data")
 
-    def maildata(name, parsed=True, from_addr=None, to_addr=None):
+    def maildata(name, from_addr=None, to_addr=None):
         if from_addr is None:
             from_addr = gencreds()[0]
         if to_addr is None:

tests/mail-data/mdn.eml

@@ -1,6 +1,6 @@
 Subject: Message opened
-From: <barbaz@c2.testrun.org>
-To: <foobar@c2.testrun.org>
+From: <{from_addr}>
+To: <{to_addr}>
 Date: Sun, 15 Oct 2023 16:43:25 +0000
 Message-ID: <Mr.78MWtlV7RAi.goCFzBhCYfy@c2.testrun.org>
 Auto-Submitted: auto-replied