The built-in function int() does not seem to have any basic unit tests (e.g. in test_builtin).  It would be good to add some.

Some cases (including edge cases) for possible inclusion:

int()
int(base='foo')  # no exception; returns 0
int(x=5)
int(x=5, base=10)  # raises TypeError
int(5.8)  # test truncation towards zero
int(-5.8)  # ditto
int('5.8')  # raises ValueError

Both positional and keyword argument combinations should be tested.