bpo-23556: [doc] Fix inaccuracy in documentation for raise without args. Improve tests for context in nested except handlers. (GH-29236)

1 files changed, 19 insertions, 3 deletions

diff --git a/Lib/test/test_raise.py b/Lib/test/test_raise.py
index 8225504..5936d75 100644
--- a/Lib/test/test_raise.py
+++ b/Lib/test/test_raise.py
@@ -303,7 +303,7 @@ class TestContext(unittest.TestCase):
             except:
                 raise OSError()
         except OSError as e:
-            self.assertEqual(e.__context__, context)
+            self.assertIs(e.__context__, context)
         else:
             self.fail("No exception raised")
 
@@ -315,7 +315,7 @@ class TestContext(unittest.TestCase):
             except:
                 raise OSError()
         except OSError as e:
-            self.assertNotEqual(e.__context__, context)
+            self.assertIsNot(e.__context__, context)
             self.assertIsInstance(e.__context__, context)
         else:
             self.fail("No exception raised")
@@ -328,7 +328,7 @@ class TestContext(unittest.TestCase):
             except:
                 raise OSError
         except OSError as e:
-            self.assertNotEqual(e.__context__, context)
+            self.assertIsNot(e.__context__, context)
             self.assertIsInstance(e.__context__, context)
         else:
             self.fail("No exception raised")
@@ -415,6 +415,22 @@ class TestContext(unittest.TestCase):
         except NameError as e:
             self.assertIsNone(e.__context__.__context__)
 
+    def test_not_last(self):
+        # Context is not necessarily the last exception
+        context = Exception("context")
+        try:
+            raise context
+        except Exception:
+            try:
+                raise Exception("caught")
+            except Exception:
+                pass
+            try:
+                raise Exception("new")
+            except Exception as exc:
+                raised = exc
+        self.assertIs(raised.__context__, context)
+
     def test_3118(self):
         # deleting the generator caused the __context__ to be cleared
         def gen():