[srp-client] add lease changing test (#7280)

tests/scripts/thread-cert/node.py

@@ -38,6 +38,7 @@ import subprocess
 import sys
 import time
 import traceback
+import typing
 import unittest
 from ipaddress import IPv6Address, IPv6Network
 from typing import Union, Dict, Optional, List, Any
@@ -654,7 +655,7 @@ class NodeImpl:
         if isinstance(pattern, str):
             pattern = re.compile(pattern)
 
-        if isinstance(pattern, re.Pattern):
+        if isinstance(pattern, typing.Pattern):
             return pattern.match(line)
         else:
             return any(NodeImpl._match_pattern(line, p) for p in pattern)
@@ -1130,6 +1131,16 @@ class NodeImpl:
         service_lines = self._expect_command_output()
         return [self._parse_srp_client_service(line) for line in service_lines]
 
+    def srp_client_set_lease_interval(self, leaseinterval: int):
+        cmd = f'srp client leaseinterval {leaseinterval}'
+        self.send_command(cmd)
+        self._expect_done()
+
+    def srp_client_get_lease_interval(self) -> int:
+        cmd = 'srp client leaseinterval'
+        self.send_command(cmd)
+        return int(self._expect_result('\d+'))
+
     def _encode_txt_entry(self, entry):
         """Encodes the TXT entry to the DNS-SD TXT record format as a HEX string.