Fix bug 1052242. Also includes rewrite of test case using unittest and

avoiding use of popen.

Doc/lib/libatexit.tex

@@ -39,6 +39,12 @@ completes), all functions registered are called in last in, first out
 order.  The assumption is that lower level modules will normally be
 imported before higher level modules and thus must be cleaned up
 later.
+
+If an exception is raised during execution of the exit handlers, a traceback
+is printed (unless SystemExit is raised) and the exception information is
+saved.  After all exit handlers have had a chance to run the last exception
+to be raised is reraised.
+
 \end{funcdesc}
 
 

Lib/atexit.py

@@ -15,9 +15,22 @@ def _run_exitfuncs():
     last in, first out.
     """
 
+    exc_info = None
     while _exithandlers:
         func, targs, kargs = _exithandlers.pop()
-        func(*targs, **kargs)
+        try:
+            func(*targs, **kargs)
+        except SystemExit:
+            exc_info = sys.exc_info()
+        except:
+            import sys, traceback
+            print >> sys.stderr, "Error in atexit._run_exitfuncs:"
+            traceback.print_exc()
+            exc_info = sys.exc_info()
+
+    if exc_info is not None:
+        raise exc_info[0], exc_info[1], exc_info[2]
+
 
 def register(func, *targs, **kargs):
     """register a function to be executed upon normal program termination
@@ -33,7 +46,6 @@ if hasattr(sys, "exitfunc"):
     # Assume it's another registered exit function - append it to our list
     register(sys.exitfunc)
 sys.exitfunc = _run_exitfuncs
-
 del sys
 
 if __name__ == "__main__":

Lib/test/test_atexit.py

@@ -1,66 +1,100 @@
-# Test the atexit module.
-from test.test_support import TESTFN, vereq, is_jython
-import atexit
-from os import popen, unlink
 import sys
-
+import unittest
-executable = sys.executable
+import StringIO
-if is_jython:
-    executable = "jython"
-
-input = """\
 import atexit
+from test import test_support
 
-def handler1():
+class TestCase(unittest.TestCase):
-    print "handler1"
+    def test_args(self):
+        # be sure args are handled properly
+        s = StringIO.StringIO()
+        sys.stdout = sys.stderr = s
+        save_handlers = atexit._exithandlers
+        atexit._exithandlers = []
+        try:
+            atexit.register(self.h1)
+            atexit.register(self.h4)
+            atexit.register(self.h4, 4, kw="abc")
+            atexit._run_exitfuncs()
+        finally:
+            sys.stdout = sys.__stdout__
+            sys.stderr = sys.__stderr__
+            atexit._exithandlers = save_handlers
+        self.assertEqual(s.getvalue(), "h4 (4,) {'kw': 'abc'}\nh4 () {}\nh1\n")
 
-def handler2(*args, **kargs):
+    def test_order(self):
-    print "handler2", args, kargs
+        # be sure handlers are executed in reverse order
+        s = StringIO.StringIO()
+        sys.stdout = sys.stderr = s
+        save_handlers = atexit._exithandlers
+        atexit._exithandlers = []
+        try:
+            atexit.register(self.h1)
+            atexit.register(self.h2)
+            atexit.register(self.h3)
+            atexit._run_exitfuncs()
+        finally:
+            sys.stdout = sys.__stdout__
+            sys.stderr = sys.__stderr__
+            atexit._exithandlers = save_handlers
+        self.assertEqual(s.getvalue(), "h3\nh2\nh1\n")
 
-atexit.register(handler1)
+    def test_sys_override(self):
-atexit.register(handler2)
+        # be sure a preset sys.exitfunc is handled properly
-atexit.register(handler2, 7, kw="abc")
+        s = StringIO.StringIO()
-"""
+        sys.stdout = sys.stderr = s
+        save_handlers = atexit._exithandlers
+        atexit._exithandlers = []
+        exfunc = sys.exitfunc
+        sys.exitfunc = self.h1
+        reload(atexit)
+        try:
+            atexit.register(self.h2)
+            atexit._run_exitfuncs()
+        finally:
+            sys.stdout = sys.__stdout__
+            sys.stderr = sys.__stderr__
+            atexit._exithandlers = save_handlers
+            sys.exitfunc = exfunc
+        self.assertEqual(s.getvalue(), "h2\nh1\n")
 
-fname = TESTFN + ".py"
+    def test_raise(self):
-f = file(fname, "w")
+        # be sure raises are handled properly
-f.write(input)
+        s = StringIO.StringIO()
-f.close()
+        sys.stdout = sys.stderr = s
+        save_handlers = atexit._exithandlers
+        atexit._exithandlers = []
+        try:
+            atexit.register(self.raise1)
+            atexit.register(self.raise2)
+            self.assertRaises(TypeError, atexit._run_exitfuncs)
+        finally:
+            sys.stdout = sys.__stdout__
+            sys.stderr = sys.__stderr__
+            atexit._exithandlers = save_handlers
+       
+    ### helpers
+    def h1(self):
+        print "h1"
 
-p = popen('"%s" %s' % (executable, fname))
+    def h2(self):
-output = p.read()
+        print "h2"
-p.close()
-vereq(output, """\
-handler2 (7,) {'kw': 'abc'}
-handler2 () {}
-handler1
-""")
 
-input = """\
+    def h3(self):
-def direct():
+        print "h3"
-    print "direct exit"
 
-import sys
+    def h4(self, *args, **kwargs):
-sys.exitfunc = direct
+        print "h4", args, kwargs
 
-# Make sure atexit doesn't drop
+    def raise1(self):
-def indirect():
+        raise TypeError
-    print "indirect exit"
 
-import atexit
+    def raise2(self):
-atexit.register(indirect)
+        raise SystemError
-"""
 
-f = file(fname, "w")
+def test_main():
-f.write(input)
+    test_support.run_unittest(TestCase)
-f.close()
 
-p = popen('"%s" %s' % (executable, fname))
-output = p.read()
-p.close()
-vereq(output, """\
-indirect exit
-direct exit
-""")
 
-unlink(fname)
+if __name__ == "__main__":
+    test_main()

Misc/NEWS

@@ -2,6 +2,17 @@
 Python News
 +++++++++++
 
+What's New in Python 2.4 release candidate 1?
+=============================================
+
+Library
+-------
+
+- Bug 1052242: If exceptions are raised by an atexit handler function an
+  attempt is made to execute the remaining handlers.  The last exception
+  raised is re-raised.
+
+
 (editors: check NEWS.help for information about editing NEWS using ReST.)
 
 What's New in Python 2.4 beta 2?