| import math |
| import random |
| import platform |
| import sys |
| import unittest |
| import warnings |
| |
| from test.test_capi.test_getargs import (Float, FloatSubclass, FloatSubclass2, |
| BadIndex2, BadFloat2, Index, BadIndex, |
| BadFloat) |
| from test.support import import_helper |
| |
| _testcapi = import_helper.import_module('_testcapi') |
| _testlimitedcapi = import_helper.import_module('_testlimitedcapi') |
| |
| NULL = None |
| |
| # For PyFloat_Pack/Unpack* |
| BIG_ENDIAN = 0 |
| LITTLE_ENDIAN = 1 |
| EPSILON = { |
| 2: 2.0 ** -11, # binary16 |
| 4: 2.0 ** -24, # binary32 |
| 8: 2.0 ** -53, # binary64 |
| } |
| |
| HAVE_IEEE_754 = float.__getformat__("double").startswith("IEEE") |
| INF = float("inf") |
| NAN = float("nan") |
| |
| |
| def make_nan(size, sign, quiet, payload=None): |
| if size == 8: |
| payload_mask = 0x7ffffffffffff |
| i = (sign << 63) + (0x7ff << 52) + (quiet << 51) |
| elif size == 4: |
| payload_mask = 0x3fffff |
| i = (sign << 31) + (0xff << 23) + (quiet << 22) |
| elif size == 2: |
| payload_mask = 0x1ff |
| i = (sign << 15) + (0x1f << 10) + (quiet << 9) |
| else: |
| raise ValueError("size must be either 2, 4, or 8") |
| if payload is None: |
| payload = random.randint(not quiet, payload_mask) |
| return i + payload |
| |
| |
| class CAPIFloatTest(unittest.TestCase): |
| def test_check(self): |
| # Test PyFloat_Check() |
| check = _testlimitedcapi.float_check |
| |
| self.assertTrue(check(4.25)) |
| self.assertTrue(check(FloatSubclass(4.25))) |
| self.assertFalse(check(Float())) |
| self.assertFalse(check(3)) |
| self.assertFalse(check(object())) |
| |
| # CRASHES check(NULL) |
| |
| def test_checkexact(self): |
| # Test PyFloat_CheckExact() |
| checkexact = _testlimitedcapi.float_checkexact |
| |
| self.assertTrue(checkexact(4.25)) |
| self.assertFalse(checkexact(FloatSubclass(4.25))) |
| self.assertFalse(checkexact(Float())) |
| self.assertFalse(checkexact(3)) |
| self.assertFalse(checkexact(object())) |
| |
| # CRASHES checkexact(NULL) |
| |
| def test_fromstring(self): |
| # Test PyFloat_FromString() |
| fromstring = _testlimitedcapi.float_fromstring |
| |
| self.assertEqual(fromstring("4.25"), 4.25) |
| self.assertEqual(fromstring(b"4.25"), 4.25) |
| self.assertRaises(ValueError, fromstring, "4.25\0") |
| self.assertRaises(ValueError, fromstring, b"4.25\0") |
| |
| self.assertEqual(fromstring(bytearray(b"4.25")), 4.25) |
| |
| self.assertEqual(fromstring(memoryview(b"4.25")), 4.25) |
| self.assertEqual(fromstring(memoryview(b"4.255")[:-1]), 4.25) |
| self.assertRaises(TypeError, fromstring, memoryview(b"4.25")[::2]) |
| |
| self.assertRaises(TypeError, fromstring, 4.25) |
| |
| # CRASHES fromstring(NULL) |
| |
| def test_fromdouble(self): |
| # Test PyFloat_FromDouble() |
| fromdouble = _testlimitedcapi.float_fromdouble |
| |
| self.assertEqual(fromdouble(4.25), 4.25) |
| |
| def test_asdouble(self): |
| # Test PyFloat_AsDouble() |
| asdouble = _testlimitedcapi.float_asdouble |
| |
| class BadFloat3: |
| def __float__(self): |
| raise RuntimeError |
| |
| self.assertEqual(asdouble(4.25), 4.25) |
| self.assertEqual(asdouble(-1.0), -1.0) |
| self.assertEqual(asdouble(42), 42.0) |
| self.assertEqual(asdouble(-1), -1.0) |
| self.assertEqual(asdouble(2**1000), float(2**1000)) |
| |
| self.assertEqual(asdouble(FloatSubclass(4.25)), 4.25) |
| self.assertEqual(asdouble(FloatSubclass2(4.25)), 4.25) |
| self.assertEqual(asdouble(Index()), 99.) |
| |
| self.assertRaises(TypeError, asdouble, BadIndex()) |
| self.assertRaises(TypeError, asdouble, BadFloat()) |
| self.assertRaises(RuntimeError, asdouble, BadFloat3()) |
| with self.assertWarns(DeprecationWarning): |
| self.assertEqual(asdouble(BadIndex2()), 1.) |
| with self.assertWarns(DeprecationWarning): |
| self.assertEqual(asdouble(BadFloat2()), 4.25) |
| with warnings.catch_warnings(): |
| warnings.simplefilter("error", DeprecationWarning) |
| self.assertRaises(DeprecationWarning, asdouble, BadFloat2()) |
| self.assertRaises(TypeError, asdouble, object()) |
| self.assertRaises(TypeError, asdouble, NULL) |
| |
| def test_getinfo(self): |
| # Test PyFloat_GetInfo() |
| getinfo = _testlimitedcapi.float_getinfo |
| |
| self.assertEqual(getinfo(), sys.float_info) |
| |
| def test_getmax(self): |
| # Test PyFloat_GetMax() |
| getmax = _testlimitedcapi.float_getmax |
| |
| self.assertEqual(getmax(), sys.float_info.max) |
| |
| def test_getmin(self): |
| # Test PyFloat_GetMax() |
| getmin = _testlimitedcapi.float_getmin |
| |
| self.assertEqual(getmin(), sys.float_info.min) |
| |
| def test_pack(self): |
| # Test PyFloat_Pack2(), PyFloat_Pack4() and PyFloat_Pack8() |
| pack = _testcapi.float_pack |
| |
| self.assertEqual(pack(2, 1.5, BIG_ENDIAN), b'>\x00') |
| self.assertEqual(pack(4, 1.5, BIG_ENDIAN), b'?\xc0\x00\x00') |
| self.assertEqual(pack(8, 1.5, BIG_ENDIAN), |
| b'?\xf8\x00\x00\x00\x00\x00\x00') |
| self.assertEqual(pack(2, 1.5, LITTLE_ENDIAN), b'\x00>') |
| self.assertEqual(pack(4, 1.5, LITTLE_ENDIAN), b'\x00\x00\xc0?') |
| self.assertEqual(pack(8, 1.5, LITTLE_ENDIAN), |
| b'\x00\x00\x00\x00\x00\x00\xf8?') |
| |
| def test_unpack(self): |
| # Test PyFloat_Unpack2(), PyFloat_Unpack4() and PyFloat_Unpack8() |
| unpack = _testcapi.float_unpack |
| |
| self.assertEqual(unpack(b'>\x00', BIG_ENDIAN), 1.5) |
| self.assertEqual(unpack(b'?\xc0\x00\x00', BIG_ENDIAN), 1.5) |
| self.assertEqual(unpack(b'?\xf8\x00\x00\x00\x00\x00\x00', BIG_ENDIAN), |
| 1.5) |
| self.assertEqual(unpack(b'\x00>', LITTLE_ENDIAN), 1.5) |
| self.assertEqual(unpack(b'\x00\x00\xc0?', LITTLE_ENDIAN), 1.5) |
| self.assertEqual(unpack(b'\x00\x00\x00\x00\x00\x00\xf8?', LITTLE_ENDIAN), |
| 1.5) |
| |
| def test_pack_unpack_roundtrip(self): |
| pack = _testcapi.float_pack |
| unpack = _testcapi.float_unpack |
| |
| large = 2.0 ** 100 |
| values = [1.0, 1.5, large, 1.0/7, math.pi] |
| if HAVE_IEEE_754: |
| values.extend((INF, NAN)) |
| for value in values: |
| for size in (2, 4, 8,): |
| if size == 2 and value == large: |
| # too large for 16-bit float |
| continue |
| rel_tol = EPSILON[size] |
| for endian in (BIG_ENDIAN, LITTLE_ENDIAN): |
| with self.subTest(value=value, size=size, endian=endian): |
| data = pack(size, value, endian) |
| value2 = unpack(data, endian) |
| if math.isnan(value): |
| self.assertTrue(math.isnan(value2), (value, value2)) |
| elif size < 8: |
| self.assertTrue(math.isclose(value2, value, rel_tol=rel_tol), |
| (value, value2)) |
| else: |
| self.assertEqual(value2, value) |
| |
| @unittest.skipUnless(HAVE_IEEE_754, "requires IEEE 754") |
| def test_pack_unpack_roundtrip_for_nans(self): |
| pack = _testcapi.float_pack |
| unpack = _testcapi.float_unpack |
| |
| for _ in range(10): |
| for size in (2, 4, 8): |
| sign = random.randint(0, 1) |
| if sys.maxsize != 2147483647: # not it 32-bit mode |
| signaling = random.randint(0, 1) |
| else: |
| # Skip sNaN's on x86 (32-bit). The problem is that sNaN |
| # doubles become qNaN doubles just by the C calling |
| # convention, there is no way to preserve sNaN doubles |
| # between C function calls with the current |
| # PyFloat_Pack/Unpack*() API. See also gh-130317 and |
| # e.g. https://developercommunity.visualstudio.com/t/155064 |
| signaling = 0 |
| if platform.machine().startswith('parisc'): |
| # HP PA RISC uses 0 for quiet, see: |
| # https://en.wikipedia.org/wiki/NaN#Encoding |
| signaling = 1 |
| i = make_nan(size, sign, not signaling) |
| data = bytes.fromhex(f'{i:x}') |
| for endian in (BIG_ENDIAN, LITTLE_ENDIAN): |
| with self.subTest(data=data, size=size, endian=endian): |
| data1 = data if endian == BIG_ENDIAN else data[::-1] |
| value = unpack(data1, endian) |
| data2 = pack(size, value, endian) |
| self.assertTrue(math.isnan(value)) |
| self.assertEqual(data1, data2) |
| |
| @unittest.skipUnless(HAVE_IEEE_754, "requires IEEE 754") |
| @unittest.skipUnless(sys.maxsize != 2147483647, "requires 64-bit mode") |
| def test_pack_unpack_nans_for_different_formats(self): |
| pack = _testcapi.float_pack |
| unpack = _testcapi.float_unpack |
| |
| for endian in (BIG_ENDIAN, LITTLE_ENDIAN): |
| with self.subTest(endian=endian): |
| byteorder = "big" if endian == BIG_ENDIAN else "little" |
| |
| # Convert sNaN to qNaN, if payload got truncated |
| data = make_nan(8, 0, False, 0x80001).to_bytes(8, byteorder) |
| snan_low = unpack(data, endian) |
| qnan4 = make_nan(4, 0, True, 0).to_bytes(4, byteorder) |
| qnan2 = make_nan(2, 0, True, 0).to_bytes(2, byteorder) |
| self.assertEqual(pack(4, snan_low, endian), qnan4) |
| self.assertEqual(pack(2, snan_low, endian), qnan2) |
| |
| # Preserve NaN type, if payload not truncated |
| data = make_nan(8, 0, False, 0x80000000001).to_bytes(8, byteorder) |
| snan_high = unpack(data, endian) |
| snan4 = make_nan(4, 0, False, 16384).to_bytes(4, byteorder) |
| snan2 = make_nan(2, 0, False, 2).to_bytes(2, byteorder) |
| self.assertEqual(pack(4, snan_high, endian), snan4) |
| self.assertEqual(pack(2, snan_high, endian), snan2) |
| |
| |
| if __name__ == "__main__": |
| unittest.main() |
