Issue #11757: select.select() now raises ValueError when a negative timeout

is passed (previously, a select.error with EINVAL would be raised).  Patch
by Charles-François Natali.

3 files changed, 10 insertions, 0 deletions

diff --git a/Lib/test/test_select.py b/Lib/test/test_select.py
index fe92f45..4a13ade 100644
--- a/Lib/test/test_select.py
+++ b/Lib/test/test_select.py
@@ -20,6 +20,7 @@ class SelectTestCase(unittest.TestCase):
         self.assertRaises(TypeError, select.select, [self.Nope()], [], [])
         self.assertRaises(TypeError, select.select, [self.Almost()], [], [])
         self.assertRaises(TypeError, select.select, [], [], [], "not a number")
+        self.assertRaises(ValueError, select.select, [], [], [], -1)
 
     def test_returned_list_identity(self):
         # See issue #8329
diff --git a/Misc/NEWS b/Misc/NEWS
index 2b43122..95e5446 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -103,6 +103,10 @@ Core and Builtins
 Library
 -------
 
+- Issue #11757: select.select() now raises ValueError when a negative timeout
+  is passed (previously, a select.error with EINVAL would be raised).  Patch
+  by Charles-François Natali.
+
 - Issue #7311: fix html.parser to accept non-ASCII attribute values.
 
 - Issue #11605: email.parser.BytesFeedParser was incorrectly converting multipart
diff --git a/Modules/selectmodule.c b/Modules/selectmodule.c
index 65e1826..5aa67dd 100644
--- a/Modules/selectmodule.c
+++ b/Modules/selectmodule.c
@@ -234,6 +234,11 @@ select_select(PyObject *self, PyObject *args)
                             "timeout period too long");
             return NULL;
         }
+        if (timeout < 0) {
+            PyErr_SetString(PyExc_ValueError,
+                        "timeout must be non-negative");
+            return NULL;
+        }
         seconds = (long)timeout;
         timeout = timeout - (double)seconds;
         tv.tv_sec = seconds;