4 files changed, 19 insertions, 14 deletions

diff --git a/src/mailman/app/lifecycle.py b/src/mailman/app/lifecycle.py
index e373bf4d9..e79073929 100644
--- a/src/mailman/app/lifecycle.py
+++ b/src/mailman/app/lifecycle.py
@@ -23,11 +23,11 @@ import logging
 
 from contextlib import suppress
 from mailman.config import config
-from mailman.interfaces.address import (
-    IEmailValidator, InvalidEmailAddressError)
+from mailman.interfaces.address import IEmailValidator
 from mailman.interfaces.domain import (
     BadDomainSpecificationError, IDomainManager)
 from mailman.interfaces.listmanager import IListManager
+from mailman.interfaces.mailinglist import InvalidListNameError
 from mailman.interfaces.member import MemberRole
 from mailman.interfaces.styles import IStyleManager
 from mailman.interfaces.usermanager import IUserManager
@@ -37,18 +37,11 @@ from zope.component import getUtility
 
 
 log = logging.getLogger('mailman.error')
-# These are the only characters allowed in list names.
+# These are the only characters allowed in list names.  A more restrictive
+# class can be specified in config.mailman.listname_chars.
 _listname_chars = re.compile('[-_.+=!$*{}~0-9a-z]', re.IGNORECASE)
 
 
-class InvalidListNameError(InvalidEmailAddressError):
-    """List name is invalid."""
-
-    def __init__(self, listname):
-        super().__init__('{}@any.example.com'.format(listname))
-        self.listname = listname
-
-
 @public
 def create_list(fqdn_listname, owners=None, style_name=None):
     """Create the named list and apply styles.
diff --git a/src/mailman/app/tests/test_lifecycle.py b/src/mailman/app/tests/test_lifecycle.py
index 4b198d973..dd320c1da 100644
--- a/src/mailman/app/tests/test_lifecycle.py
+++ b/src/mailman/app/tests/test_lifecycle.py
@@ -60,8 +60,8 @@ class TestLifecycle(unittest.TestCase):
             '(unterminated character set|'
             'unexpected end of regular expression)$'
             )
-        # Remove the list.
-        remove_list(mlist)
+        # Check that the list was actually created.
+        self.assertIs(os.path.isdir(mlist.data_path), True)
 
     @configuration('mailman', listname_chars='[a-z]')
     def test_listname_with_minimal_listname_chars(self):
diff --git a/src/mailman/config/schema.cfg b/src/mailman/config/schema.cfg
index 9386caed1..fde431b60 100644
--- a/src/mailman/config/schema.cfg
+++ b/src/mailman/config/schema.cfg
@@ -77,7 +77,9 @@ html_to_plain_text_command: /usr/bin/lynx -dump $filename
 
 # Specify what characters are allowed in list names.  Characters outside of
 # the class [-_.+=!$*{}~0-9a-z] matched case insensitively are never allowed,
-# but this specifies a subset as the only allowable characters.
+# but this specifies a subset as the only allowable characters.  This must be
+# a valid character class regexp or the effect on list creation is
+# unpredictable.
 listname_chars: [-_.0-9a-z]
 
 
diff --git a/src/mailman/interfaces/mailinglist.py b/src/mailman/interfaces/mailinglist.py
index ddc5a13b6..f066ba3c8 100644
--- a/src/mailman/interfaces/mailinglist.py
+++ b/src/mailman/interfaces/mailinglist.py
@@ -18,12 +18,22 @@
 """Interface for a mailing list."""
 
 from enum import Enum
+from mailman.interfaces.address import InvalidEmailAddressError
 from mailman.interfaces.member import MemberRole
 from public import public
 from zope.interface import Attribute, Interface
 
 
 @public
+class InvalidListNameError(InvalidEmailAddressError):
+    """List name is invalid."""
+
+    def __init__(self, listname):
+        super().__init__('{}@'.format(listname))
+        self.listname = listname
+
+
+@public
 class DMARCMitigateAction(Enum):
     # Mitigations to apply to messages From: domains publishing an applicable
     # DMARC policy, or unconditionally depending on settings.