[Python-Dev] [Python-checkins] cpython (3.3): Issue #16045: add more unit tests for built-in int()
chris.jerdonek at gmail.com
Sun Dec 23 22:47:46 CET 2012
On Sun, Dec 23, 2012 at 12:03 PM, Terry Reedy <tjreedy at udel.edu> wrote:
>> + # For example, PyPy 1.9.0 raised TypeError for these cases because it
>> + # expects x to be a string if base is given.
>> + @support.cpython_only
>> + def test_base_arg_with_no_x_arg(self):
>> + self.assertEquals(int(base=6), 0)
>> + # Even invalid bases don't raise an exception.
>> + self.assertEquals(int(base=1), 0)
>> + self.assertEquals(int(base=1000), 0)
>> + self.assertEquals(int(base='foo'), 0)
> I think the above behavior is buggy and should be changed rather than frozen
> into CPython with a test. According to the docs, PyPy does it right.
I support further discussion here. (I did draft the patch, but it was
a first version. I did not commit the patch.)
> The current online doc gives the signature as
> int(x, base=10) <<where x is s string>>
> The 3.3.0 docstring says
> "When converting a string, use the optional base. It is an error to supply
> a base when converting a non-string."
One way to partially explain CPython's behavior is that when base is
provided, the function behaves as if x defaults to '0' rather than 0.
This is similar to the behavior of str(), which defaults to b'' when
encoding or errors is provided, but otherwise defaults to '':
> Certainly, accepting any object as a base, violating "The allowed values are
> 0 and 2-36." just because giving a base is itself invalid is crazy.
For further background (and you can see this is the 2.7 commit),
int(base='foo') did raise TypeError in 2.7, but this particular case
was relaxed in Python 3.
More information about the Python-Dev