diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py index a5b8c46f949..c8feaa870b0 100644 --- a/Lib/test/support/__init__.py +++ b/Lib/test/support/__init__.py @@ -2621,3 +2621,42 @@ def disable_faulthandler(): finally: if is_enabled: faulthandler.enable(file=fd, all_threads=True) + + +class SaveSignals: + """ + Save an restore signal handlers. + + This class is only able to save/restore signal handlers registered + by the Python signal module: see bpo-13285 for "external" signal + handlers. + """ + + def __init__(self): + import signal + self.signal = signal + self.signals = list(range(1, signal.NSIG)) + # SIGKILL and SIGSTOP signals cannot be ignored nor catched + for signame in ('SIGKILL', 'SIGSTOP'): + try: + signum = getattr(signal, signame) + except AttributeError: + continue + self.signals.remove(signum) + self.handlers = {} + + def save(self): + for signum in self.signals: + handler = self.signal.getsignal(signum) + if handler is None: + # getsignal() returns None if a signal handler was not + # registered by the Python signal module, + # and the handler is not SIG_DFL nor SIG_IGN. + # + # Ignore the signal: we cannot restore the handler. + continue + self.handlers[signum] = handler + + def restore(self): + for signum, handler in self.handlers.items(): + self.signal.signal(signum, handler) diff --git a/Lib/test/test_curses.py b/Lib/test/test_curses.py index 0d0b160d764..b0a28908da7 100644 --- a/Lib/test/test_curses.py +++ b/Lib/test/test_curses.py @@ -15,7 +15,7 @@ import sys import tempfile import unittest -from test.support import requires, import_module, verbose +from test.support import requires, import_module, verbose, SaveSignals # Optionally test curses module. This currently requires that the # 'curses' resource be given on the regrtest command line using the -u @@ -63,6 +63,8 @@ class TestCurses(unittest.TestCase): del cls.tmp def setUp(self): + self.save_signals = SaveSignals() + self.save_signals.save() if verbose: # just to make the test output a little more readable print() @@ -72,6 +74,7 @@ class TestCurses(unittest.TestCase): def tearDown(self): curses.resetty() curses.endwin() + self.save_signals.restore() def test_window_funcs(self): "Test the methods of windows"