Closes issue 15505. unittest.installHandler and non-callable signal handlers.

1 files changed, 15 insertions, 1 deletions

diff --git a/Lib/unittest/signals.py b/Lib/unittest/signals.py
index fc31043..e6a5fc5 100644
--- a/Lib/unittest/signals.py
+++ b/Lib/unittest/signals.py
@@ -9,6 +9,20 @@ __unittest = True
 class _InterruptHandler(object):
     def __init__(self, default_handler):
         self.called = False
+        self.original_handler = default_handler
+        if isinstance(default_handler, int):
+            if default_handler == signal.SIG_DFL:
+                # Pretend it's signal.default_int_handler instead.
+                default_handler = signal.default_int_handler
+            elif default_handler == signal.SIG_IGN:
+                # Not quite the same thing as SIG_IGN, but the closest we
+                # can make it: do nothing.
+                def default_handler(unused_signum, unused_frame):
+                    pass
+            else:
+                raise TypeError("expected SIGINT signal handler to be "
+                                "signal.SIG_IGN, signal.SIG_DFL, or a "
+                                "callable object")
         self.default_handler = default_handler
 
     def __call__(self, signum, frame):
@@ -54,4 +68,4 @@ def removeHandler(method=None):
 
     global _interrupt_handler
     if _interrupt_handler is not None:
-        signal.signal(signal.SIGINT, _interrupt_handler.default_handler)
+        signal.signal(signal.SIGINT, _interrupt_handler.original_handler)