@@ -448,4 +448,13 @@ def _parse_args(args, **kwargs):
         # --forever implies --failfast
         ns.failfast = True
 
+    if ns.huntrleaks:
+        warmup, repetitions, _ = ns.huntrleaks
+        if warmup < 1 or repetitions < 1:
+            msg = ("Invalid values for the --huntrleaks/-R parameters. The "
+                   "number of warmups and repetitions must be at least 1 "
+                   "each (1:1).")
+            print(msg, file=sys.stderr, flush=True)
+            sys.exit(2)
+
     return ns
@@ -9,10 +9,10 @@
 import tempfile
 import time
 import unittest
-from test.libregrtest.cmdline import _parse_args
+from test.libregrtest.cmdline import _parse_args, Namespace
 from test.libregrtest.runtest import (
     findtests, split_test_packages, runtest, abs_module_name,
-    PROGRESS_MIN_TIME, State, MatchTestsDict, RunTests)
+    PROGRESS_MIN_TIME, State, MatchTestsDict, RunTests, TestResult)
 from test.libregrtest.setup import setup_tests
 from test.libregrtest.pgo import setup_pgo_tests
 from test.libregrtest.utils import (strip_py_suffix, count, format_duration,
@@ -35,6 +35,9 @@
 EXITCODE_INTERRUPTED = 130
 
 
+TestsList = list[str]
+
+
 class Regrtest:
     """Execute a test suite.
 
@@ -58,24 +61,24 @@ class Regrtest:
     directly to set the values that would normally be set by flags
     on the command line.
     """
-    def __init__(self):
+    def __init__(self, ns: Namespace):
         # Namespace of command line options
-        self.ns = None
+        self.ns: Namespace = ns
 
         # tests
         self.tests = []
         self.selected = []
         self.all_runtests: list[RunTests] = []
 
         # test results
-        self.good: list[str] = []
-        self.bad: list[str] = []
-        self.rerun_bad: list[str] = []
-        self.skipped: list[str] = []
-        self.resource_denied: list[str] = []
-        self.environment_changed: list[str] = []
-        self.run_no_tests: list[str] = []
-        self.rerun: list[str] = []
+        self.good: TestsList = []
+        self.bad: TestsList = []
+        self.rerun_bad: TestsList = []
+        self.skipped: TestsList = []
+        self.resource_denied: TestsList = []
+        self.environment_changed: TestsList = []
+        self.run_no_tests: TestsList = []
+        self.rerun: TestsList = []
 
         self.need_rerun: list[TestResult] = []
         self.first_state: str | None = None
@@ -184,29 +187,7 @@ def display_progress(self, test_index, text):
             line = f"{line}/{fails}"
         self.log(f"[{line}] {text}")
 
-    def parse_args(self, kwargs):
-        ns = _parse_args(sys.argv[1:], **kwargs)
-
-        if ns.xmlpath:
-            support.junit_xml_list = self.testsuite_xml = []
-
-        strip_py_suffix(ns.args)
-
-        if ns.huntrleaks:
-            warmup, repetitions, _ = ns.huntrleaks
-            if warmup < 1 or repetitions < 1:
-                msg = ("Invalid values for the --huntrleaks/-R parameters. The "
-                       "number of warmups and repetitions must be at least 1 "
-                       "each (1:1).")
-                print(msg, file=sys.stderr, flush=True)
-                sys.exit(2)
-
-        if ns.tempdir:
-            ns.tempdir = os.path.expanduser(ns.tempdir)
-
-        self.ns = ns
-
-    def find_tests(self, tests):
+    def find_tests(self):
         ns = self.ns
         single = ns.single
         fromfile = ns.fromfile
@@ -216,8 +197,6 @@ def find_tests(self, tests):
         starting_test = ns.start
         randomize = ns.randomize
 
-        self.tests = tests
-
         if single:
             self.next_single_filename = os.path.join(self.tmp_dir, 'pynexttest')
             try:
@@ -737,8 +716,12 @@ def fix_umask(self):
                 os.umask(old_mask)
 
     def set_temp_dir(self):
-        if self.ns.tempdir:
-            self.tmp_dir = self.ns.tempdir
+        ns = self.ns
+        if ns.tempdir:
+            ns.tempdir = os.path.expanduser(ns.tempdir)
+
+        if ns.tempdir:
+            self.tmp_dir = ns.tempdir
 
         if not self.tmp_dir:
             # When tests are run from the Python build directory, it is best practice
@@ -795,14 +778,20 @@ def cleanup(self):
                 print("Remove file: %s" % name)
                 os_helper.unlink(name)
 
-    def main(self, tests=None, **kwargs):
-        self.parse_args(kwargs)
+    def main(self, tests: TestsList | None = None):
+        ns = self.ns
+        self.tests = tests
+
+        if ns.xmlpath:
+            support.junit_xml_list = self.testsuite_xml = []
+
+        strip_py_suffix(ns.args)
 
         self.set_temp_dir()
 
         self.fix_umask()
 
-        if self.ns.cleanup:
+        if ns.cleanup:
             self.cleanup()
             sys.exit(0)
 
@@ -817,9 +806,9 @@ def main(self, tests=None, **kwargs):
                 # When using multiprocessing, worker processes will use test_cwd
                 # as their parent temporary directory. So when the main process
                 # exit, it removes also subdirectories of worker processes.
-                self.ns.tempdir = test_cwd
+                ns.tempdir = test_cwd
 
-                self._main(tests, kwargs)
+                self._main()
         except SystemExit as exc:
             # bpo-38203: Python can hang at exit in Py_Finalize(), especially
             # on threading._shutdown() call: put a timeout
@@ -862,7 +851,7 @@ def action_run_tests(self):
         self.display_summary()
         self.finalize()
 
-    def _main(self, tests, kwargs):
+    def _main(self):
         if self.is_worker():
             from test.libregrtest.runtest_mp import run_tests_worker
             run_tests_worker(self.ns.worker_args)
@@ -872,7 +861,7 @@ def _main(self, tests, kwargs):
             input("Press any key to continue...")
 
         setup_tests(self.ns)
-        self.find_tests(tests)
+        self.find_tests()
 
         exitcode = 0
         if self.ns.list_tests:
@@ -888,4 +877,5 @@ def _main(self, tests, kwargs):
 
 def main(tests=None, **kwargs):
     """Run the Python suite."""
-    Regrtest().main(tests=tests, **kwargs)
+    ns = _parse_args(sys.argv[1:], **kwargs)
+    Regrtest(ns).main(tests=tests)