Fix corner case for Random.choice() and add tests.
diff --git a/Lib/random.py b/Lib/random.py
index 88b8f6d..0886562 100644
--- a/Lib/random.py
+++ b/Lib/random.py
@@ -239,7 +239,11 @@
def choice(self, seq):
"""Choose a random element from a non-empty sequence."""
- return seq[self._randbelow(len(seq))] # raises IndexError if seq is empty
+ try:
+ i = self._randbelow(len(seq))
+ except ValueError:
+ raise IndexError('Cannot choose from an empty sequence')
+ return seq[i]
def shuffle(self, x, random=None, int=int):
"""x, random=random.random -> shuffle list x in place; return None.