Issue #16655: Explain why Idle's test_calltips has 'fragile' tests of builtins.
diff --git a/Lib/idlelib/idle_test/test_calltips.py b/Lib/idlelib/idle_test/test_calltips.py
index 5254c60..da52e88 100644
--- a/Lib/idlelib/idle_test/test_calltips.py
+++ b/Lib/idlelib/idle_test/test_calltips.py
@@ -33,8 +33,16 @@
signature = ct.get_argspec # 2.7 and 3.x use different functions
class Get_signatureTest(unittest.TestCase):
+ # The signature function must return a string, even if blank.
+ # Test a variety of objects to be sure that none cause it to raise
+ # (quite aside from getting as correct an answer as possible).
+ # The tests of builtins may break if inspect or the docstrings change,
+ # but a red buildbot is better than a user crash (as has happened).
+ # For a simple mismatch, change the expected output to the actual.
def test_builtins(self):
+ # These test will break if
+
# Python class that inherits builtin methods
class List(list): "List() doc"
# Simulate builtin with no docstring for default argspec test