test: add error-path tests for all bug fixes

- test_doveauth: invalid localpart chars rejected, concurrent same-account creation
- test_expire: --mdir filtering uses msg.path correctly
- test_metadata: TURN exception returns N\n, success returns credentials
- test_turnserver: socket timeout, connection refused, happy path
- test_dns: get_dkim_entry returns (None, None) on CalledProcessError
- test_rshell: dovecot_recalc_quota handles empty/malformed output

chatmaild/src/chatmaild/tests/test_doveauth.py

@@ -120,6 +120,60 @@ def test_handle_dovecot_protocol_iterate(gencreds, example_config):
     assert not lines[2]
 
 
+def test_invalid_localpart_characters(make_config):
+    """Test that is_allowed_to_create rejects localparts with invalid characters."""
+    config = make_config("chat.example.org", {"username_min_length": "3"})
+    password = "zequ0Aimuchoodaechik"
+    domain = config.mail_domain
+
+    # valid localparts
+    assert is_allowed_to_create(config, f"abc123@{domain}", password)
+    assert is_allowed_to_create(config, f"a.b-c_d@{domain}", password)
+
+    # uppercase rejected
+    assert not is_allowed_to_create(config, f"Abc123@{domain}", password)
+    assert not is_allowed_to_create(config, f"ABCDEFG@{domain}", password)
+
+    # spaces and special chars rejected
+    assert not is_allowed_to_create(config, f"a b cde@{domain}", password)
+    assert not is_allowed_to_create(config, f"abc+def@{domain}", password)
+    assert not is_allowed_to_create(config, f"abc!def@{domain}", password)
+    assert not is_allowed_to_create(config, f"ab@cdef@{domain}", password)
+    assert not is_allowed_to_create(config, f"abc/def@{domain}", password)
+    assert not is_allowed_to_create(config, f"abc\\def@{domain}", password)
+
+
+def test_concurrent_creation_same_account(dictproxy):
+    """Test that concurrent creation of the same account doesn't corrupt password."""
+    addr = "racetest1@chat.example.org"
+    password = "zequ0Aimuchoodaechik"
+    num_threads = 10
+    results = queue.Queue()
+
+    def create():
+        try:
+            res = dictproxy.lookup_passdb(addr, password)
+            results.put(("ok", res))
+        except Exception:
+            results.put(("err", traceback.format_exc()))
+
+    threads = [threading.Thread(target=create, daemon=True) for _ in range(num_threads)]
+    for t in threads:
+        t.start()
+    for t in threads:
+        t.join(timeout=10)
+
+    passwords_seen = set()
+    for _ in range(num_threads):
+        status, res = results.get()
+        if status == "err":
+            pytest.fail(f"concurrent creation failed\n{res}")
+        passwords_seen.add(res["password"])
+
+    # all threads must see the same password hash
+    assert len(passwords_seen) == 1
+
+
 def test_50_concurrent_lookups_different_accounts(gencreds, dictproxy):
     num_threads = 50
     req_per_thread = 5

chatmaild/src/chatmaild/tests/test_expire.py

@@ -112,6 +112,43 @@ def test_report(mbox1, example_config):
     report_main(args)
 
 
+def test_report_mdir_filters_by_path(mbox1, example_config):
+    """Test that Report with mdir='cur' only counts messages in cur/ subdirectory."""
+    from chatmaild.fsreport import Report
+
+    now = datetime.utcnow().timestamp()
+
+    # Set password mtime to old enough so min_login_age check passes
+    password = Path(mbox1.basedir).joinpath("password")
+    old_time = now - 86400 * 10  # 10 days ago
+    os.utime(password, (old_time, old_time))
+
+    # Reload mailbox with updated mtime
+    from chatmaild.expire import MailboxStat
+
+    mbox = MailboxStat(mbox1.basedir)
+
+    # Report without mdir — should count all messages
+    rep_all = Report(now=now, min_login_age=1, mdir=None)
+    rep_all.process_mailbox_stat(mbox)
+    total_all = rep_all.message_buckets[0]
+
+    # Report with mdir='cur' — should only count cur/ messages
+    rep_cur = Report(now=now, min_login_age=1, mdir="cur")
+    rep_cur.process_mailbox_stat(mbox)
+    total_cur = rep_cur.message_buckets[0]
+
+    # Report with mdir='new' — should only count new/ messages
+    rep_new = Report(now=now, min_login_age=1, mdir="new")
+    rep_new.process_mailbox_stat(mbox)
+    total_new = rep_new.message_buckets[0]
+
+    # cur has 500-byte msg, new has 600-byte msg (from fill_mbox)
+    assert total_cur == 500
+    assert total_new == 600
+    assert total_all == 500 + 600
+
+
 def test_expiry_cli_basic(example_config, mbox1):
     args = (str(example_config._inipath),)
     expiry_main(args)

chatmaild/src/chatmaild/tests/test_metadata.py

@@ -314,6 +314,51 @@ def test_persistent_queue_items(tmp_path, testaddr, token):
     assert not queue_item < item2 and not item2 < queue_item
 
 
+def test_turn_credentials_exception_returns_N(notifier, metadata, monkeypatch):
+    """Test that turn_credentials() failure returns N\\n instead of crashing."""
+    import chatmaild.metadata
+
+    dictproxy = MetadataDictProxy(
+        notifier=notifier,
+        metadata=metadata,
+        turn_hostname="turn.example.org",
+    )
+
+    def mock_turn_credentials():
+        raise ConnectionRefusedError("socket not available")
+
+    monkeypatch.setattr(chatmaild.metadata, "turn_credentials", mock_turn_credentials)
+
+    transactions = {}
+    res = dictproxy.handle_dovecot_request(
+        "Lshared/0123/vendor/vendor.dovecot/pvt/server/vendor/deltachat/turn"
+        "\tuser@example.org",
+        transactions,
+    )
+    assert res == "N\n"
+
+
+def test_turn_credentials_success(notifier, metadata, monkeypatch):
+    """Test that valid turn_credentials() returns TURN URI."""
+    import chatmaild.metadata
+
+    dictproxy = MetadataDictProxy(
+        notifier=notifier,
+        metadata=metadata,
+        turn_hostname="turn.example.org",
+    )
+
+    monkeypatch.setattr(chatmaild.metadata, "turn_credentials", lambda: "user:pass")
+
+    transactions = {}
+    res = dictproxy.handle_dovecot_request(
+        "Lshared/0123/vendor/vendor.dovecot/pvt/server/vendor/deltachat/turn"
+        "\tuser@example.org",
+        transactions,
+    )
+    assert res == "Oturn.example.org:3478:user:pass\n"
+
+
 def test_iroh_relay(dictproxy):
     rfile = io.BytesIO(
         b"\n".join(

chatmaild/src/chatmaild/tests/test_turnserver.py

@@ -0,0 +1,73 @@
+import socket
+import threading
+import time
+from unittest.mock import patch
+
+import pytest
+
+from chatmaild.turnserver import turn_credentials
+
+SOCKET_PATH = "/run/chatmail-turn/turn.socket"
+
+
+@pytest.fixture
+def turn_socket(tmp_path):
+    """Create a real Unix socket server at a temp path."""
+    sock_path = str(tmp_path / "turn.socket")
+    server = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+    server.bind(sock_path)
+    server.listen(1)
+    yield sock_path, server
+    server.close()
+
+
+def _call_turn_credentials(sock_path):
+    """Call turn_credentials but connect to sock_path instead of hardcoded path."""
+    original_connect = socket.socket.connect
+
+    def patched_connect(self, address):
+        if address == SOCKET_PATH:
+            address = sock_path
+        return original_connect(self, address)
+
+    with patch.object(socket.socket, "connect", patched_connect):
+        return turn_credentials()
+
+
+def test_turn_credentials_timeout(turn_socket):
+    """Server accepts but never responds — must raise socket.timeout."""
+    sock_path, server = turn_socket
+
+    def accept_and_hang():
+        conn, _ = server.accept()
+        time.sleep(30)
+        conn.close()
+
+    t = threading.Thread(target=accept_and_hang, daemon=True)
+    t.start()
+
+    with pytest.raises(socket.timeout):
+        _call_turn_credentials(sock_path)
+
+
+def test_turn_credentials_connection_refused(tmp_path):
+    """Socket file doesn't exist — must raise ConnectionRefusedError or FileNotFoundError."""
+    missing = str(tmp_path / "nonexistent.socket")
+    with pytest.raises((ConnectionRefusedError, FileNotFoundError)):
+        _call_turn_credentials(missing)
+
+
+def test_turn_credentials_success(turn_socket):
+    """Server responds with credentials — must return stripped string."""
+    sock_path, server = turn_socket
+
+    def respond():
+        conn, _ = server.accept()
+        conn.sendall(b"testuser:testpass\n")
+        conn.close()
+
+    t = threading.Thread(target=respond, daemon=True)
+    t.start()
+
+    result = _call_turn_credentials(sock_path)
+    assert result == "testuser:testpass"

cmdeploy/src/cmdeploy/tests/test_dns.py

@@ -60,6 +60,29 @@ def mockdns(request, mockdns_base, mockdns_expected):
     return mockdns_base
 
 
+class TestGetDkimEntry:
+    def test_dkim_entry_returns_tuple_on_success(self, mockdns):
+        entry, web_entry = remote.rdns.get_dkim_entry(
+            "some.domain", "", dkim_selector="opendkim"
+        )
+        # May return None,None if openssl not available, but should never crash
+        if entry is not None:
+            assert "opendkim._domainkey.some.domain" in entry
+            assert "opendkim._domainkey.some.domain" in web_entry
+
+    def test_dkim_entry_returns_none_tuple_on_error(self, monkeypatch):
+        """CalledProcessError must return (None, None), not bare None."""
+        from subprocess import CalledProcessError
+
+        def failing_shell(command, fail_ok=False, print=print):
+            raise CalledProcessError(1, command)
+
+        monkeypatch.setattr(remote.rdns, "shell", failing_shell)
+        result = remote.rdns.get_dkim_entry("some.domain", "", dkim_selector="opendkim")
+        assert result == (None, None)
+        assert result[0] is None and result[1] is None
+
+
 class TestPerformInitialChecks:
     def test_perform_initial_checks_ok1(self, mockdns, mockdns_expected):
         remote_data = remote.rdns.perform_initial_checks("some.domain")

cmdeploy/src/cmdeploy/tests/test_rshell.py

@@ -0,0 +1,68 @@
+from unittest.mock import patch
+
+from cmdeploy.remote.rshell import dovecot_recalc_quota
+
+
+def test_dovecot_recalc_quota_normal_output():
+    """Normal doveadm output returns parsed dict."""
+    normal_output = (
+        "Quota name Type    Value  Limit  %\n"
+        "User quota STORAGE     5 102400  0\n"
+        "User quota MESSAGE     2      -  0\n"
+    )
+
+    with patch("cmdeploy.remote.rshell.shell", return_value=normal_output):
+        result = dovecot_recalc_quota("user@example.org")
+
+    # shell is called twice (recalc + get), patch returns same for both
+    assert result == {"value": 5, "limit": 102400, "percent": 0}
+
+
+def test_dovecot_recalc_quota_empty_output():
+    """Empty doveadm output (trailing newline) must not IndexError."""
+    call_count = [0]
+
+    def mock_shell(cmd):
+        call_count[0] += 1
+        if "recalc" in cmd:
+            return ""
+        # quota get returns only empty lines
+        return "\n\n"
+
+    with patch("cmdeploy.remote.rshell.shell", side_effect=mock_shell):
+        result = dovecot_recalc_quota("user@example.org")
+
+    assert result is None
+
+
+def test_dovecot_recalc_quota_malformed_output():
+    """Malformed output with too few columns must not crash."""
+    call_count = [0]
+
+    def mock_shell(cmd):
+        call_count[0] += 1
+        if "recalc" in cmd:
+            return ""
+        # partial line, fewer than 6 parts
+        return "Quota name\nUser quota STORAGE\n"
+
+    with patch("cmdeploy.remote.rshell.shell", side_effect=mock_shell):
+        result = dovecot_recalc_quota("user@example.org")
+
+    assert result is None
+
+
+def test_dovecot_recalc_quota_header_only():
+    """Only header line, no data rows."""
+    call_count = [0]
+
+    def mock_shell(cmd):
+        call_count[0] += 1
+        if "recalc" in cmd:
+            return ""
+        return "Quota name Type    Value  Limit  %\n"
+
+    with patch("cmdeploy.remote.rshell.shell", side_effect=mock_shell):
+        result = dovecot_recalc_quota("user@example.org")
+
+    assert result is None