Update test_atexit to CPython 3.10

Author: fanninpm

Lib/test/test_atexit.py

@@ -1,174 +1,52 @@
-import sys
-import unittest
-import io
 import atexit
 import os
+import sys
+import textwrap
+import unittest
 from test import support
 from test.support import script_helper
 
-### helpers
-def h1():
-    print("h1")
-
-def h2():
-    print("h2")
-
-def h3():
-    print("h3")
-
-def h4(*args, **kwargs):
-    print("h4", args, kwargs)
-
-def raise1():
-    raise TypeError
-
-def raise2():
-    raise SystemError
-
-def exit():
-    raise SystemExit
-
 
 class GeneralTest(unittest.TestCase):
+    def test_general(self):
+        # Run _test_atexit.py in a subprocess since it calls atexit._clear()
+        script = support.findfile("_test_atexit.py")
+        script_helper.run_test_script(script)
 
-    def setUp(self):
-        self.save_stdout = sys.stdout
-        self.save_stderr = sys.stderr
-        self.stream = io.StringIO()
-        sys.stdout = sys.stderr = self.stream
-        atexit._clear()
-
-    def tearDown(self):
-        sys.stdout = self.save_stdout
-        sys.stderr = self.save_stderr
-        atexit._clear()
-
-    def test_args(self):
-        # be sure args are handled properly
-        atexit.register(h1)
-        atexit.register(h4)
-        atexit.register(h4, 4, kw="abc")
-        atexit._run_exitfuncs()
-
-        self.assertEqual(self.stream.getvalue(),
-                            "h4 (4,) {'kw': 'abc'}\nh4 () {}\nh1\n")
-
-    def test_badargs(self):
-        atexit.register(lambda: 1, 0, 0, (x for x in (1,2)), 0, 0)
-        self.assertRaises(TypeError, atexit._run_exitfuncs)
-
-    def test_order(self):
-        # be sure handlers are executed in reverse order
-        atexit.register(h1)
-        atexit.register(h2)
-        atexit.register(h3)
-        atexit._run_exitfuncs()
-
-        self.assertEqual(self.stream.getvalue(), "h3\nh2\nh1\n")
-
-    def test_raise(self):
-        # be sure raises are handled properly
-        atexit.register(raise1)
-        atexit.register(raise2)
-
-        self.assertRaises(TypeError, atexit._run_exitfuncs)
-
-    def test_raise_unnormalized(self):
-        # Issue #10756: Make sure that an unnormalized exception is
-        # handled properly
-        atexit.register(lambda: 1 / 0)
-
-        self.assertRaises(ZeroDivisionError, atexit._run_exitfuncs)
-        self.assertIn("ZeroDivisionError", self.stream.getvalue())
-
-    def test_exit(self):
-        # be sure a SystemExit is handled properly
-        atexit.register(exit)
-
-        self.assertRaises(SystemExit, atexit._run_exitfuncs)
-        self.assertEqual(self.stream.getvalue(), '')
-
-    def test_print_tracebacks(self):
-        # Issue #18776: the tracebacks should be printed when errors occur.
-        def f():
-            1/0  # one
-        def g():
-            1/0  # two
-        def h():
-            1/0  # three
-        atexit.register(f)
-        atexit.register(g)
-        atexit.register(h)
-
-        self.assertRaises(ZeroDivisionError, atexit._run_exitfuncs)
-        stderr = self.stream.getvalue()
-        self.assertEqual(stderr.count("ZeroDivisionError"), 3)
-        self.assertIn("# one", stderr)
-        self.assertIn("# two", stderr)
-        self.assertIn("# three", stderr)
-
-    def test_stress(self):
-        a = [0]
-        def inc():
-            a[0] += 1
-
-        for i in range(128):
-            atexit.register(inc)
-        atexit._run_exitfuncs()
-
-        self.assertEqual(a[0], 128)
-
-    def test_clear(self):
-        a = [0]
-        def inc():
-            a[0] += 1
-
-        atexit.register(inc)
-        atexit._clear()
-        atexit._run_exitfuncs()
-
-        self.assertEqual(a[0], 0)
-
-    def test_unregister(self):
-        a = [0]
-        def inc():
-            a[0] += 1
-        def dec():
-            a[0] -= 1
-
-        for i in range(4):
-            atexit.register(inc)
-        atexit.register(dec)
-        atexit.unregister(inc)
-        atexit._run_exitfuncs()
-
-        self.assertEqual(a[0], -1)
-
-    def test_bound_methods(self):
-        l = []
-        atexit.register(l.append, 5)
-        atexit._run_exitfuncs()
-        self.assertEqual(l, [5])
-
-        atexit.unregister(l.append)
-        atexit._run_exitfuncs()
-        self.assertEqual(l, [5])
-
+class FunctionalTest(unittest.TestCase):
     def test_shutdown(self):
         # Actually test the shutdown mechanism in a subprocess
-        code = """if 1:
+        code = textwrap.dedent("""
             import atexit
 
             def f(msg):
                 print(msg)
 
             atexit.register(f, "one")
             atexit.register(f, "two")
-            """
+        """)
         res = script_helper.assert_python_ok("-c", code)
         self.assertEqual(res.out.decode().splitlines(), ["two", "one"])
         self.assertFalse(res.err)
 
+    def test_atexit_instances(self):
+        # bpo-42639: It is safe to have more than one atexit instance.
+        code = textwrap.dedent("""
+            import sys
+            import atexit as atexit1
+            del sys.modules['atexit']
+            import atexit as atexit2
+            del sys.modules['atexit']
+
+            assert atexit2 is not atexit1
+
+            atexit1.register(print, "atexit1")
+            atexit2.register(print, "atexit2")
+        """)
+        res = script_helper.assert_python_ok("-c", code)
+        self.assertEqual(res.out.decode().splitlines(), ["atexit2", "atexit1"])
+        self.assertFalse(res.err)
+
 
 @support.cpython_only
 class SubinterpreterTest(unittest.TestCase):
@@ -178,13 +56,13 @@ def test_callbacks_leak(self):
         # take care to free callbacks in its per-subinterpreter module
         # state.
         n = atexit._ncallbacks()
-        code = r"""if 1:
+        code = textwrap.dedent(r"""
             import atexit
             def f():
                 pass
             atexit.register(f)
             del atexit
-            """
+        """)
         ret = support.run_in_subinterp(code)
         self.assertEqual(ret, 0)
         self.assertEqual(atexit._ncallbacks(), n)
@@ -193,13 +71,13 @@ def test_callbacks_leak_refcycle(self):
         # Similar to the above, but with a refcycle through the atexit
         # module.
         n = atexit._ncallbacks()
-        code = r"""if 1:
+        code = textwrap.dedent(r"""
             import atexit
             def f():
                 pass
             atexit.register(f)
             atexit.__atexit = atexit
-            """
+        """)
         ret = support.run_in_subinterp(code)
         self.assertEqual(ret, 0)
         self.assertEqual(atexit._ncallbacks(), n)
@@ -210,13 +88,13 @@ def test_callback_on_subinterpreter_teardown(self):
         expected = b"The test has passed!"
         r, w = os.pipe()
 
-        code = r"""if 1:
+        code = textwrap.dedent(r"""
             import os
             import atexit
             def callback():
                 os.write({:d}, b"The test has passed!")
             atexit.register(callback)
-        """.format(w)
+        """.format(w))
         ret = support.run_in_subinterp(code)
         os.close(w)
         self.assertEqual(os.read(r, len(expected)), expected)