lib-python.2.5.test.test_long.py Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jython Show documentation
Show all versions of jython Show documentation
Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
import unittest
from test import test_support
import random
# Used for lazy formatting of failure messages
class Frm(object):
def __init__(self, format, *args):
self.format = format
self.args = args
def __str__(self):
return self.format % self.args
# SHIFT should match the value in longintrepr.h for best testing.
SHIFT = 15
BASE = 2 ** SHIFT
MASK = BASE - 1
KARATSUBA_CUTOFF = 70 # from longobject.c
# Max number of base BASE digits to use in test cases. Doubling
# this will more than double the runtime.
MAXDIGITS = 15
# build some special values
special = map(long, [0, 1, 2, BASE, BASE >> 1])
special.append(0x5555555555555555L)
special.append(0xaaaaaaaaaaaaaaaaL)
# some solid strings of one bits
p2 = 4L # 0 and 1 already added
for i in range(2*SHIFT):
special.append(p2 - 1)
p2 = p2 << 1
del p2
# add complements & negations
special = special + map(lambda x: ~x, special) + \
map(lambda x: -x, special)
class LongTest(unittest.TestCase):
# Get quasi-random long consisting of ndigits digits (in base BASE).
# quasi == the most-significant digit will not be 0, and the number
# is constructed to contain long strings of 0 and 1 bits. These are
# more likely than random bits to provoke digit-boundary errors.
# The sign of the number is also random.
def getran(self, ndigits):
self.assert_(ndigits > 0)
nbits_hi = ndigits * SHIFT
nbits_lo = nbits_hi - SHIFT + 1
answer = 0L
nbits = 0
r = int(random.random() * (SHIFT * 2)) | 1 # force 1 bits to start
while nbits < nbits_lo:
bits = (r >> 1) + 1
bits = min(bits, nbits_hi - nbits)
self.assert_(1 <= bits <= SHIFT)
nbits = nbits + bits
answer = answer << bits
if r & 1:
answer = answer | ((1 << bits) - 1)
r = int(random.random() * (SHIFT * 2))
self.assert_(nbits_lo <= nbits <= nbits_hi)
if random.random() < 0.5:
answer = -answer
return answer
# Get random long consisting of ndigits random digits (relative to base
# BASE). The sign bit is also random.
def getran2(ndigits):
answer = 0L
for i in xrange(ndigits):
answer = (answer << SHIFT) | random.randint(0, MASK)
if random.random() < 0.5:
answer = -answer
return answer
def check_division(self, x, y):
eq = self.assertEqual
q, r = divmod(x, y)
q2, r2 = x//y, x%y
pab, pba = x*y, y*x
eq(pab, pba, Frm("multiplication does not commute for %r and %r", x, y))
eq(q, q2, Frm("divmod returns different quotient than / for %r and %r", x, y))
eq(r, r2, Frm("divmod returns different mod than %% for %r and %r", x, y))
eq(x, q*y + r, Frm("x != q*y + r after divmod on x=%r, y=%r", x, y))
if y > 0:
self.assert_(0 <= r < y, Frm("bad mod from divmod on %r and %r", x, y))
else:
self.assert_(y < r <= 0, Frm("bad mod from divmod on %r and %r", x, y))
def test_division(self):
digits = range(1, MAXDIGITS+1) + range(KARATSUBA_CUTOFF,
KARATSUBA_CUTOFF + 14)
digits.append(KARATSUBA_CUTOFF * 3)
for lenx in digits:
x = self.getran(lenx)
for leny in digits:
y = self.getran(leny) or 1L
self.check_division(x, y)
def test_karatsuba(self):
digits = range(1, 5) + range(KARATSUBA_CUTOFF, KARATSUBA_CUTOFF + 10)
digits.extend([KARATSUBA_CUTOFF * 10, KARATSUBA_CUTOFF * 100])
bits = [digit * SHIFT for digit in digits]
# Test products of long strings of 1 bits -- (2**x-1)*(2**y-1) ==
# 2**(x+y) - 2**x - 2**y + 1, so the proper result is easy to check.
for abits in bits:
a = (1L << abits) - 1
for bbits in bits:
if bbits < abits:
continue
b = (1L << bbits) - 1
x = a * b
y = ((1L << (abits + bbits)) -
(1L << abits) -
(1L << bbits) +
1)
self.assertEqual(x, y,
Frm("bad result for a*b: a=%r, b=%r, x=%r, y=%r", a, b, x, y))
def check_bitop_identities_1(self, x):
eq = self.assertEqual
eq(x & 0, 0, Frm("x & 0 != 0 for x=%r", x))
eq(x | 0, x, Frm("x | 0 != x for x=%r", x))
eq(x ^ 0, x, Frm("x ^ 0 != x for x=%r", x))
eq(x & -1, x, Frm("x & -1 != x for x=%r", x))
eq(x | -1, -1, Frm("x | -1 != -1 for x=%r", x))
eq(x ^ -1, ~x, Frm("x ^ -1 != ~x for x=%r", x))
eq(x, ~~x, Frm("x != ~~x for x=%r", x))
eq(x & x, x, Frm("x & x != x for x=%r", x))
eq(x | x, x, Frm("x | x != x for x=%r", x))
eq(x ^ x, 0, Frm("x ^ x != 0 for x=%r", x))
eq(x & ~x, 0, Frm("x & ~x != 0 for x=%r", x))
eq(x | ~x, -1, Frm("x | ~x != -1 for x=%r", x))
eq(x ^ ~x, -1, Frm("x ^ ~x != -1 for x=%r", x))
eq(-x, 1 + ~x, Frm("not -x == 1 + ~x for x=%r", x))
eq(-x, ~(x-1), Frm("not -x == ~(x-1) forx =%r", x))
for n in xrange(2*SHIFT):
p2 = 2L ** n
eq(x << n >> n, x,
Frm("x << n >> n != x for x=%r, n=%r", (x, n)))
eq(x // p2, x >> n,
Frm("x // p2 != x >> n for x=%r n=%r p2=%r", (x, n, p2)))
eq(x * p2, x << n,
Frm("x * p2 != x << n for x=%r n=%r p2=%r", (x, n, p2)))
eq(x & -p2, x >> n << n,
Frm("not x & -p2 == x >> n << n for x=%r n=%r p2=%r", (x, n, p2)))
eq(x & -p2, x & ~(p2 - 1),
Frm("not x & -p2 == x & ~(p2 - 1) for x=%r n=%r p2=%r", (x, n, p2)))
def check_bitop_identities_2(self, x, y):
eq = self.assertEqual
eq(x & y, y & x, Frm("x & y != y & x for x=%r, y=%r", (x, y)))
eq(x | y, y | x, Frm("x | y != y | x for x=%r, y=%r", (x, y)))
eq(x ^ y, y ^ x, Frm("x ^ y != y ^ x for x=%r, y=%r", (x, y)))
eq(x ^ y ^ x, y, Frm("x ^ y ^ x != y for x=%r, y=%r", (x, y)))
eq(x & y, ~(~x | ~y), Frm("x & y != ~(~x | ~y) for x=%r, y=%r", (x, y)))
eq(x | y, ~(~x & ~y), Frm("x | y != ~(~x & ~y) for x=%r, y=%r", (x, y)))
eq(x ^ y, (x | y) & ~(x & y),
Frm("x ^ y != (x | y) & ~(x & y) for x=%r, y=%r", (x, y)))
eq(x ^ y, (x & ~y) | (~x & y),
Frm("x ^ y == (x & ~y) | (~x & y) for x=%r, y=%r", (x, y)))
eq(x ^ y, (x | y) & (~x | ~y),
Frm("x ^ y == (x | y) & (~x | ~y) for x=%r, y=%r", (x, y)))
def check_bitop_identities_3(self, x, y, z):
eq = self.assertEqual
eq((x & y) & z, x & (y & z),
Frm("(x & y) & z != x & (y & z) for x=%r, y=%r, z=%r", (x, y, z)))
eq((x | y) | z, x | (y | z),
Frm("(x | y) | z != x | (y | z) for x=%r, y=%r, z=%r", (x, y, z)))
eq((x ^ y) ^ z, x ^ (y ^ z),
Frm("(x ^ y) ^ z != x ^ (y ^ z) for x=%r, y=%r, z=%r", (x, y, z)))
eq(x & (y | z), (x & y) | (x & z),
Frm("x & (y | z) != (x & y) | (x & z) for x=%r, y=%r, z=%r", (x, y, z)))
eq(x | (y & z), (x | y) & (x | z),
Frm("x | (y & z) != (x | y) & (x | z) for x=%r, y=%r, z=%r", (x, y, z)))
def test_bitop_identities(self):
for x in special:
self.check_bitop_identities_1(x)
digits = xrange(1, MAXDIGITS+1)
for lenx in digits:
x = self.getran(lenx)
self.check_bitop_identities_1(x)
for leny in digits:
y = self.getran(leny)
self.check_bitop_identities_2(x, y)
self.check_bitop_identities_3(x, y, self.getran((lenx + leny)//2))
def slow_format(self, x, base):
if (x, base) == (0, 8):
# this is an oddball!
return "0L"
digits = []
sign = 0
if x < 0:
sign, x = 1, -x
while x:
x, r = divmod(x, base)
digits.append(int(r))
digits.reverse()
digits = digits or [0]
return '-'[:sign] + \
{8: '0', 10: '', 16: '0x'}[base] + \
"".join(map(lambda i: "0123456789abcdef"[i], digits)) + "L"
def check_format_1(self, x):
for base, mapper in (8, oct), (10, repr), (16, hex):
got = mapper(x)
expected = self.slow_format(x, base)
msg = Frm("%s returned %r but expected %r for %r",
mapper.__name__, got, expected, x)
self.assertEqual(got, expected, msg)
self.assertEqual(long(got, 0), x, Frm('long("%s", 0) != %r', got, x))
# str() has to be checked a little differently since there's no
# trailing "L"
got = str(x)
expected = self.slow_format(x, 10)[:-1]
msg = Frm("%s returned %r but expected %r for %r",
mapper.__name__, got, expected, x)
self.assertEqual(got, expected, msg)
def test_format(self):
for x in special:
self.check_format_1(x)
for i in xrange(10):
for lenx in xrange(1, MAXDIGITS+1):
x = self.getran(lenx)
self.check_format_1(x)
def test_misc(self):
import sys
# check the extremes in int<->long conversion
hugepos = sys.maxint
hugeneg = -hugepos - 1
hugepos_aslong = long(hugepos)
hugeneg_aslong = long(hugeneg)
self.assertEqual(hugepos, hugepos_aslong, "long(sys.maxint) != sys.maxint")
self.assertEqual(hugeneg, hugeneg_aslong,
"long(-sys.maxint-1) != -sys.maxint-1")
# long -> int should not fail for hugepos_aslong or hugeneg_aslong
x = int(hugepos_aslong)
try:
self.assertEqual(x, hugepos,
"converting sys.maxint to long and back to int fails")
except OverflowError:
self.fail("int(long(sys.maxint)) overflowed!")
if not isinstance(x, int):
raise TestFailed("int(long(sys.maxint)) should have returned int")
x = int(hugeneg_aslong)
try:
self.assertEqual(x, hugeneg,
"converting -sys.maxint-1 to long and back to int fails")
except OverflowError:
self.fail("int(long(-sys.maxint-1)) overflowed!")
if not isinstance(x, int):
raise TestFailed("int(long(-sys.maxint-1)) should have "
"returned int")
# but long -> int should overflow for hugepos+1 and hugeneg-1
x = hugepos_aslong + 1
try:
y = int(x)
except OverflowError:
self.fail("int(long(sys.maxint) + 1) mustn't overflow")
self.assert_(isinstance(y, long),
"int(long(sys.maxint) + 1) should have returned long")
x = hugeneg_aslong - 1
try:
y = int(x)
except OverflowError:
self.fail("int(long(-sys.maxint-1) - 1) mustn't overflow")
self.assert_(isinstance(y, long),
"int(long(-sys.maxint-1) - 1) should have returned long")
class long2(long):
pass
x = long2(1L<<100)
y = int(x)
self.assert_(type(y) is long,
"overflowing int conversion must return long not long subtype")
# long -> Py_ssize_t conversion
class X(object):
def __getslice__(self, i, j):
return i, j
self.assertEqual(X()[-5L:7L], (-5, 7))
# use the clamping effect to test the smallest and largest longs
# that fit a Py_ssize_t
slicemin, slicemax = X()[-2L**100:2L**100]
self.assertEqual(X()[slicemin:slicemax], (slicemin, slicemax))
# ----------------------------------- tests of auto int->long conversion
def test_auto_overflow(self):
import math, sys
special = [0, 1, 2, 3, sys.maxint-1, sys.maxint, sys.maxint+1]
sqrt = int(math.sqrt(sys.maxint))
special.extend([sqrt-1, sqrt, sqrt+1])
special.extend([-i for i in special])
def checkit(*args):
# Heavy use of nested scopes here!
self.assertEqual(got, expected,
Frm("for %r expected %r got %r", args, expected, got))
for x in special:
longx = long(x)
expected = -longx
got = -x
checkit('-', x)
for y in special:
longy = long(y)
expected = longx + longy
got = x + y
checkit(x, '+', y)
expected = longx - longy
got = x - y
checkit(x, '-', y)
expected = longx * longy
got = x * y
checkit(x, '*', y)
if y:
expected = longx / longy
got = x / y
checkit(x, '/', y)
expected = longx // longy
got = x // y
checkit(x, '//', y)
expected = divmod(longx, longy)
got = divmod(longx, longy)
checkit(x, 'divmod', y)
if abs(y) < 5 and not (x == 0 and y < 0):
expected = longx ** longy
got = x ** y
checkit(x, '**', y)
for z in special:
if z != 0 :
if y >= 0:
expected = pow(longx, longy, long(z))
got = pow(x, y, z)
checkit('pow', x, y, '%', z)
else:
self.assertRaises(TypeError, pow,longx, longy, long(z))
def test_float_overflow(self):
import math
for x in -2.0, -1.0, 0.0, 1.0, 2.0:
self.assertEqual(float(long(x)), x)
shuge = '12345' * 120
huge = 1L << 30000
mhuge = -huge
namespace = {'huge': huge, 'mhuge': mhuge, 'shuge': shuge, 'math': math}
for test in ["float(huge)", "float(mhuge)",
"complex(huge)", "complex(mhuge)",
"complex(huge, 1)", "complex(mhuge, 1)",
"complex(1, huge)", "complex(1, mhuge)",
"1. + huge", "huge + 1.", "1. + mhuge", "mhuge + 1.",
"1. - huge", "huge - 1.", "1. - mhuge", "mhuge - 1.",
"1. * huge", "huge * 1.", "1. * mhuge", "mhuge * 1.",
"1. // huge", "huge // 1.", "1. // mhuge", "mhuge // 1.",
"1. / huge", "huge / 1.", "1. / mhuge", "mhuge / 1.",
"1. ** huge", "huge ** 1.", "1. ** mhuge", "mhuge ** 1.",
"math.sin(huge)", "math.sin(mhuge)",
"math.sqrt(huge)", "math.sqrt(mhuge)", # should do better
"math.floor(huge)", "math.floor(mhuge)"]:
self.assertRaises(OverflowError, eval, test, namespace)
# XXX Perhaps float(shuge) can raise OverflowError on some box?
# The comparison should not.
self.assertNotEqual(float(shuge), int(shuge),
"float(shuge) should not equal int(shuge)")
def test_logs(self):
import math
LOG10E = math.log10(math.e)
for exp in range(10) + [100, 1000, 10000]:
value = 10 ** exp
log10 = math.log10(value)
self.assertAlmostEqual(log10, exp)
# log10(value) == exp, so log(value) == log10(value)/log10(e) ==
# exp/LOG10E
expected = exp / LOG10E
log = math.log(value)
self.assertAlmostEqual(log, expected)
for bad in -(1L << 10000), -2L, 0L:
self.assertRaises(ValueError, math.log, bad)
self.assertRaises(ValueError, math.log10, bad)
def test_mixed_compares(self):
eq = self.assertEqual
import math
import sys
# We're mostly concerned with that mixing floats and longs does the
# right stuff, even when longs are too large to fit in a float.
# The safest way to check the results is to use an entirely different
# method, which we do here via a skeletal rational class (which
# represents all Python ints, longs and floats exactly).
class Rat:
def __init__(self, value):
if isinstance(value, (int, long)):
self.n = value
self.d = 1
elif isinstance(value, float):
# Convert to exact rational equivalent.
f, e = math.frexp(abs(value))
assert f == 0 or 0.5 <= f < 1.0
# |value| = f * 2**e exactly
# Suck up CHUNK bits at a time; 28 is enough so that we suck
# up all bits in 2 iterations for all known binary double-
# precision formats, and small enough to fit in an int.
CHUNK = 28
top = 0
# invariant: |value| = (top + f) * 2**e exactly
while f:
f = math.ldexp(f, CHUNK)
digit = int(f)
assert digit >> CHUNK == 0
top = (top << CHUNK) | digit
f -= digit
assert 0.0 <= f < 1.0
e -= CHUNK
# Now |value| = top * 2**e exactly.
if e >= 0:
n = top << e
d = 1
else:
n = top
d = 1 << -e
if value < 0:
n = -n
self.n = n
self.d = d
assert float(n) / float(d) == value
else:
raise TypeError("can't deal with %r" % val)
def __cmp__(self, other):
if not isinstance(other, Rat):
other = Rat(other)
return cmp(self.n * other.d, self.d * other.n)
cases = [0, 0.001, 0.99, 1.0, 1.5, 1e20, 1e200]
# 2**48 is an important boundary in the internals. 2**53 is an
# important boundary for IEEE double precision.
for t in 2.0**48, 2.0**50, 2.0**53:
cases.extend([t - 1.0, t - 0.3, t, t + 0.3, t + 1.0,
long(t-1), long(t), long(t+1)])
cases.extend([0, 1, 2, sys.maxint, float(sys.maxint)])
# 1L<<20000 should exceed all double formats. long(1e200) is to
# check that we get equality with 1e200 above.
t = long(1e200)
cases.extend([0L, 1L, 2L, 1L << 20000, t-1, t, t+1])
cases.extend([-x for x in cases])
for x in cases:
Rx = Rat(x)
for y in cases:
Ry = Rat(y)
Rcmp = cmp(Rx, Ry)
xycmp = cmp(x, y)
eq(Rcmp, xycmp, Frm("%r %r %d %d", x, y, Rcmp, xycmp))
eq(x == y, Rcmp == 0, Frm("%r == %r %d", x, y, Rcmp))
eq(x != y, Rcmp != 0, Frm("%r != %r %d", x, y, Rcmp))
eq(x < y, Rcmp < 0, Frm("%r < %r %d", x, y, Rcmp))
eq(x <= y, Rcmp <= 0, Frm("%r <= %r %d", x, y, Rcmp))
eq(x > y, Rcmp > 0, Frm("%r > %r %d", x, y, Rcmp))
eq(x >= y, Rcmp >= 0, Frm("%r >= %r %d", x, y, Rcmp))
def test_main():
test_support.run_unittest(LongTest)
if __name__ == "__main__":
test_main()