bpo-41833: threading.Thread now uses the target name (GH-22357)

Lib/test/test_threading.py

@@ -20,6 +20,7 @@
 import signal
 import textwrap
 
+from unittest import mock
 from test import lock_tests
 from test import support
 
@@ -86,6 +87,33 @@ def tearDown(self):
 
 class ThreadTests(BaseTestCase):
 
+    @cpython_only
+    def test_name(self):
+        def func(): pass
+
+        thread = threading.Thread(name="myname1")
+        self.assertEqual(thread.name, "myname1")
+
+        # Convert int name to str
+        thread = threading.Thread(name=123)
+        self.assertEqual(thread.name, "123")
+
+        # target name is ignored if name is specified
+        thread = threading.Thread(target=func, name="myname2")
+        self.assertEqual(thread.name, "myname2")
+
+        with mock.patch.object(threading, '_counter', return_value=2):
+            thread = threading.Thread(name="")
+            self.assertEqual(thread.name, "Thread-2")
+
+        with mock.patch.object(threading, '_counter', return_value=3):
+            thread = threading.Thread()
+            self.assertEqual(thread.name, "Thread-3")
+
+        with mock.patch.object(threading, '_counter', return_value=5):
+            thread = threading.Thread(target=func)
+            self.assertEqual(thread.name, "Thread-5 (func)")
+
     # Create a bunch of threads, let each do some work, wait until all are
     # done.
     def test_various_ops(self):
@@ -531,7 +559,7 @@ def test_main_thread_after_fork_from_nonmain_thread(self):
             import os, threading, sys
             from test import support
 
-            def f():
+            def func():
                 pid = os.fork()
                 if pid == 0:
                     main = threading.main_thread()
@@ -544,14 +572,14 @@ def f():
                 else:
                     support.wait_process(pid, exitcode=0)
 
-            th = threading.Thread(target=f)
+            th = threading.Thread(target=func)
             th.start()
             th.join()
         """
         _, out, err = assert_python_ok("-c", code)
         data = out.decode().replace('\r', '')
         self.assertEqual(err, b"")
-        self.assertEqual(data, "Thread-1\nTrue\nTrue\n")
+        self.assertEqual(data, "Thread-1 (func)\nTrue\nTrue\n")
 
     def test_main_thread_during_shutdown(self):
         # bpo-31516: current_thread() should still point to the main thread