#17572: Avoid chained exceptions while passing bad directives to time.strptime(). Initial patch by Claudiu Popa.

2 files changed, 12 insertions, 0 deletions

diff --git a/Lib/test/test_strptime.py b/Lib/test/test_strptime.py
index 90aac5b..68e6a67 100644
--- a/Lib/test/test_strptime.py
+++ b/Lib/test/test_strptime.py
@@ -218,6 +218,12 @@ class StrptimeTests(unittest.TestCase):
             else:
                 self.fail("'%s' did not raise ValueError" % bad_format)
 
+    def test_strptime_exception_context(self):
+        # check that this doesn't chain exceptions needlessly (see #17572)
+        with self.assertRaises(ValueError) as e:
+            _strptime._strptime_time('', '%D')
+        self.assertIs(e.exception.__suppress_context__, True)
+
     def test_unconverteddata(self):
         # Check ValueError is raised when there is unconverted data
         self.assertRaises(ValueError, _strptime._strptime_time, "10 12", "%m")
diff --git a/Lib/test/test_time.py b/Lib/test/test_time.py
index da0f555..0e4d702 100644
--- a/Lib/test/test_time.py
+++ b/Lib/test/test_time.py
@@ -193,6 +193,12 @@ class TimeTestCase(unittest.TestCase):
         self.assertRaises(TypeError, time.strptime, b'2009', "%Y")
         self.assertRaises(TypeError, time.strptime, '2009', b'%Y')
 
+    def test_strptime_exception_context(self):
+        # check that this doesn't chain exceptions needlessly (see #17572)
+        with self.assertRaises(ValueError) as e:
+            time.strptime('', '%D')
+        self.assertIs(e.exception.__suppress_context__, True)
+
     def test_asctime(self):
         time.asctime(time.gmtime(self.t))