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Issue #16148: implemented PEP 424

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This commit is contained in:
Armin Ronacher 2012-10-06 14:03:24 +02:00
parent ef08fb1f04
commit aa9a79d279
14 changed files with 161 additions and 82 deletions
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78
Objects/abstract.c
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@ -64,49 +64,67 @@ PyObject_Length(PyObject *o)
}
#define PyObject_Length PyObject_Size
int
_PyObject_HasLen(PyObject *o) {
return (Py_TYPE(o)->tp_as_sequence && Py_TYPE(o)->tp_as_sequence->sq_length) ||
(Py_TYPE(o)->tp_as_mapping && Py_TYPE(o)->tp_as_mapping->mp_length);
}
/* The length hint function returns a non-negative value from o.__len__()
or o.__length_hint__(). If those methods aren't found or return a negative
value, then the defaultvalue is returned. If one of the calls fails,
this function returns -1.
or o.__length_hint__(). If those methods aren't found. If one of the calls
fails this function returns -1.
*/
Py_ssize_t
_PyObject_LengthHint(PyObject *o, Py_ssize_t defaultvalue)
PyObject_LengthHint(PyObject *o, Py_ssize_t defaultvalue)
{
_Py_IDENTIFIER(__length_hint__);
PyObject *ro, *hintmeth;
Py_ssize_t rv;
/* try o.__len__() */
rv = PyObject_Size(o);
if (rv >= 0)
return rv;
if (PyErr_Occurred()) {
if (!PyErr_ExceptionMatches(PyExc_TypeError))
Py_ssize_t res = PyObject_Length(o);
if (res < 0 && PyErr_Occurred()) {
if (!PyErr_ExceptionMatches(PyExc_TypeError)) {
return -1;
}
PyErr_Clear();
}
/* try o.__length_hint__() */
hintmeth = _PyObject_LookupSpecial(o, &PyId___length_hint__);
if (hintmeth == NULL) {
if (PyErr_Occurred())
return -1;
else
return defaultvalue;
else {
return res;
}
ro = PyObject_CallFunctionObjArgs(hintmeth, NULL);
Py_DECREF(hintmeth);
if (ro == NULL) {
if (!PyErr_ExceptionMatches(PyExc_TypeError))
PyObject *hint = _PyObject_LookupSpecial(o, &PyId___length_hint__);
if (hint == NULL) {
if (PyErr_Occurred()) {
return -1;
PyErr_Clear();
}
return defaultvalue;
}
rv = PyLong_Check(ro) ? PyLong_AsSsize_t(ro) : defaultvalue;
Py_DECREF(ro);
return rv;
PyObject *result = PyObject_CallFunctionObjArgs(hint, NULL);
Py_DECREF(hint);
if (result == NULL) {
if (PyErr_ExceptionMatches(PyExc_TypeError)) {
PyErr_Clear();
return defaultvalue;
}
return -1;
}
else if (result == Py_NotImplemented) {
Py_DECREF(result);
return defaultvalue;
}
if (!PyLong_Check(result)) {
PyErr_Format(PyExc_TypeError, "Length hint must be an integer, not %s",
Py_TYPE(result)->tp_name);
Py_DECREF(result);
return -1;
}
defaultvalue = PyLong_AsSsize_t(result);
Py_DECREF(result);
if (defaultvalue < 0 && PyErr_Occurred()) {
return -1;
}
if (defaultvalue < 0) {
PyErr_Format(PyExc_ValueError, "__length_hint__() should return >= 0");
return -1;
}
return defaultvalue;
}
PyObject *
@ -1687,7 +1705,7 @@ PySequence_Tuple(PyObject *v)
return NULL;
/* Guess result size and allocate space. */
n = _PyObject_LengthHint(v, 10);
n = PyObject_LengthHint(v, 10);
if (n == -1)
goto Fail;
result = PyTuple_New(n);