diff options
| -rw-r--r-- | Lib/test/test_float.py | 21 | ||||
| -rw-r--r-- | Lib/test/test_getargs2.py | 6 | ||||
| -rw-r--r-- | Misc/NEWS | 5 | ||||
| -rw-r--r-- | Objects/abstract.c | 30 | ||||
| -rw-r--r-- | Objects/floatobject.c | 46 |
5 files changed, 76 insertions, 32 deletions
diff --git a/Lib/test/test_float.py b/Lib/test/test_float.py index 427f044..68b212e 100644 --- a/Lib/test/test_float.py +++ b/Lib/test/test_float.py @@ -161,11 +161,12 @@ class GeneralFloatCases(unittest.TestCase): def __float__(self): return float(str(self)) + 1 - self.assertAlmostEqual(float(Foo1()), 42.) - self.assertAlmostEqual(float(Foo2()), 42.) - self.assertAlmostEqual(float(Foo3(21)), 42.) + self.assertEqual(float(Foo1()), 42.) + self.assertEqual(float(Foo2()), 42.) + with self.assertWarns(DeprecationWarning): + self.assertEqual(float(Foo3(21)), 42.) self.assertRaises(TypeError, float, Foo4(42)) - self.assertAlmostEqual(float(FooStr('8')), 9.) + self.assertEqual(float(FooStr('8')), 9.) class Foo5: def __float__(self): @@ -176,10 +177,14 @@ class GeneralFloatCases(unittest.TestCase): class F: def __float__(self): return OtherFloatSubclass(42.) - self.assertAlmostEqual(float(F()), 42.) - self.assertIs(type(float(F())), OtherFloatSubclass) - self.assertAlmostEqual(FloatSubclass(F()), 42.) - self.assertIs(type(FloatSubclass(F())), FloatSubclass) + with self.assertWarns(DeprecationWarning): + self.assertEqual(float(F()), 42.) + with self.assertWarns(DeprecationWarning): + self.assertIs(type(float(F())), float) + with self.assertWarns(DeprecationWarning): + self.assertEqual(FloatSubclass(F()), 42.) + with self.assertWarns(DeprecationWarning): + self.assertIs(type(FloatSubclass(F())), FloatSubclass) def test_is_integer(self): self.assertFalse((1.1).is_integer()) diff --git a/Lib/test/test_getargs2.py b/Lib/test/test_getargs2.py index 8a51e0b..ecc1908 100644 --- a/Lib/test/test_getargs2.py +++ b/Lib/test/test_getargs2.py @@ -365,7 +365,8 @@ class Float_TestCase(unittest.TestCase): self.assertEqual(getargs_f(FloatSubclass(7.5)), 7.5) self.assertEqual(getargs_f(FloatSubclass2(7.5)), 7.5) self.assertRaises(TypeError, getargs_f, BadFloat()) - self.assertEqual(getargs_f(BadFloat2()), 4.25) + with self.assertWarns(DeprecationWarning): + self.assertEqual(getargs_f(BadFloat2()), 4.25) self.assertEqual(getargs_f(BadFloat3(7.5)), 7.5) for x in (FLT_MIN, -FLT_MIN, FLT_MAX, -FLT_MAX, INF, -INF): @@ -390,7 +391,8 @@ class Float_TestCase(unittest.TestCase): self.assertEqual(getargs_d(FloatSubclass(7.5)), 7.5) self.assertEqual(getargs_d(FloatSubclass2(7.5)), 7.5) self.assertRaises(TypeError, getargs_d, BadFloat()) - self.assertEqual(getargs_d(BadFloat2()), 4.25) + with self.assertWarns(DeprecationWarning): + self.assertEqual(getargs_d(BadFloat2()), 4.25) self.assertEqual(getargs_d(BadFloat3(7.5)), 7.5) for x in (DBL_MIN, -DBL_MIN, DBL_MAX, -DBL_MAX, INF, -INF): @@ -10,6 +10,11 @@ What's New in Python 3.6.0 alpha 2 Core and Builtins ----------------- +- Issue #26983: float() now always return an instance of exact float. + The deprecation warning is emitted if __float__ returns an instance of + a strict subclass of float. In a future versions of Python this can + be an error. + - Issue #27097: Python interpreter is now about 7% faster due to optimized instruction decoding. Based on patch by Demur Rumed. diff --git a/Objects/abstract.c b/Objects/abstract.c index 3e1ff97..12dd6a1 100644 --- a/Objects/abstract.c +++ b/Objects/abstract.c @@ -1351,21 +1351,39 @@ PyNumber_Float(PyObject *o) if (o == NULL) return null_error(); + if (PyFloat_CheckExact(o)) { + Py_INCREF(o); + return o; + } m = o->ob_type->tp_as_number; if (m && m->nb_float) { /* This should include subclasses of float */ PyObject *res = m->nb_float(o); - if (res && !PyFloat_Check(res)) { + double val; + if (!res || PyFloat_CheckExact(res)) { + return res; + } + if (!PyFloat_Check(res)) { PyErr_Format(PyExc_TypeError, - "__float__ returned non-float (type %.200s)", - res->ob_type->tp_name); + "%.50s.__float__ returned non-float (type %.50s)", + o->ob_type->tp_name, res->ob_type->tp_name); Py_DECREF(res); return NULL; } - return res; + /* Issue #26983: warn if 'res' not of exact type float. */ + if (PyErr_WarnFormat(PyExc_DeprecationWarning, 1, + "%.50s.__float__ returned non-float (type %.50s). " + "The ability to return an instance of a strict subclass of float " + "is deprecated, and may be removed in a future version of Python.", + o->ob_type->tp_name, res->ob_type->tp_name)) { + Py_DECREF(res); + return NULL; + } + val = PyFloat_AS_DOUBLE(res); + Py_DECREF(res); + return PyFloat_FromDouble(val); } if (PyFloat_Check(o)) { /* A float subclass with nb_float == NULL */ - PyFloatObject *po = (PyFloatObject *)o; - return PyFloat_FromDouble(po->ob_fval); + return PyFloat_FromDouble(PyFloat_AS_DOUBLE(o)); } return PyFloat_FromString(o); } diff --git a/Objects/floatobject.c b/Objects/floatobject.c index 5b2742a..da600f4 100644 --- a/Objects/floatobject.c +++ b/Objects/floatobject.c @@ -215,35 +215,49 @@ double PyFloat_AsDouble(PyObject *op) { PyNumberMethods *nb; - PyFloatObject *fo; + PyObject *res; double val; - if (op && PyFloat_Check(op)) - return PyFloat_AS_DOUBLE((PyFloatObject*) op); - if (op == NULL) { PyErr_BadArgument(); return -1; } - if ((nb = Py_TYPE(op)->tp_as_number) == NULL || nb->nb_float == NULL) { - PyErr_SetString(PyExc_TypeError, "a float is required"); - return -1; + if (PyFloat_Check(op)) { + return PyFloat_AS_DOUBLE(op); } - fo = (PyFloatObject*) (*nb->nb_float) (op); - if (fo == NULL) - return -1; - if (!PyFloat_Check(fo)) { - Py_DECREF(fo); - PyErr_SetString(PyExc_TypeError, - "nb_float should return float object"); + nb = Py_TYPE(op)->tp_as_number; + if (nb == NULL || nb->nb_float == NULL) { + PyErr_Format(PyExc_TypeError, "must be real number, not %.50s", + op->ob_type->tp_name); return -1; } - val = PyFloat_AS_DOUBLE(fo); - Py_DECREF(fo); + res = (*nb->nb_float) (op); + if (res == NULL) { + return -1; + } + if (!PyFloat_CheckExact(res)) { + if (!PyFloat_Check(res)) { + PyErr_Format(PyExc_TypeError, + "%.50s.__float__ returned non-float (type %.50s)", + op->ob_type->tp_name, res->ob_type->tp_name); + Py_DECREF(res); + return -1; + } + if (PyErr_WarnFormat(PyExc_DeprecationWarning, 1, + "%.50s.__float__ returned non-float (type %.50s). " + "The ability to return an instance of a strict subclass of float " + "is deprecated, and may be removed in a future version of Python.", + op->ob_type->tp_name, res->ob_type->tp_name)) { + Py_DECREF(res); + return -1; + } + } + val = PyFloat_AS_DOUBLE(res); + Py_DECREF(res); return val; } |