diff options
Diffstat (limited to 'Lib/test/test_strtod.py')
| -rw-r--r-- | Lib/test/test_strtod.py | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/Lib/test/test_strtod.py b/Lib/test/test_strtod.py index e39558a2f6..7a42a893b1 100644 --- a/Lib/test/test_strtod.py +++ b/Lib/test/test_strtod.py @@ -2,12 +2,15 @@ # introduced in Python 2.7 and 3.1. import random -import struct import unittest import re import sys import test.support +if getattr(sys, 'float_repr_style', '') != 'short': + raise unittest.SkipTest('correctly-rounded string->float conversions ' + 'not available on this system') + # Correctly rounded str -> float in pure Python, for comparison. strtod_parser = re.compile(r""" # A numeric string consists of: @@ -19,6 +22,8 @@ strtod_parser = re.compile(r""" # A numeric string consists of: \Z """, re.VERBOSE | re.IGNORECASE).match +# Pure Python version of correctly rounded string->float conversion. +# Avoids any use of floating-point by returning the result as a hex string. def strtod(s, mant_dig=53, min_exp = -1021, max_exp = 1024): """Convert a finite decimal string to a hex string representing an IEEE 754 binary64 float. Return 'inf' or '-inf' on overflow. @@ -78,8 +83,6 @@ def strtod(s, mant_dig=53, min_exp = -1021, max_exp = 1024): TEST_SIZE = 10 -@unittest.skipUnless(getattr(sys, 'float_repr_style', '') == 'short', - "applies only when using short float repr style") class StrtodTests(unittest.TestCase): def check_strtod(self, s): """Compare the result of Python's builtin correctly rounded @@ -257,6 +260,10 @@ class StrtodTests(unittest.TestCase): '18487398785991994634182916638542680759613590482273e-357', '32002864200581033134358724675198044527469366773928e-358', '94393431193180696942841837085033647913224148539854e-358', + '73608278998966969345824653500136787876436005957953e-358', + '64774478836417299491718435234611299336288082136054e-358', + '13704940134126574534878641876947980878824688451169e-357', + '46697445774047060960624497964425416610480524760471e-358', # failing case for bug introduced by METD in r77451 (attempted # fix for issue 7632, bug 2), and fixed in r77482. '28639097178261763178489759107321392745108491825303e-311', @@ -380,6 +387,13 @@ class StrtodTests(unittest.TestCase): '999999999999999944488848768742172978818416595458984375e-54', '9999999999999999444888487687421729788184165954589843749999999e-54', '9999999999999999444888487687421729788184165954589843750000001e-54', + # Value found by Rick Regan that gives a result of 2**-968 + # under Gay's dtoa.c (as of Nov 04, 2010); since fixed. + # (Fixed some time ago in Python's dtoa.c.) + '0.0000000000000000000000000000000000000000100000000' #... + '000000000576129113423785429971690421191214034235435' #... + '087147763178149762956868991692289869941246658073194' #... + '51982237978882039897143840789794921875', ] for s in test_strings: self.check_strtod(s) |