# this will at least quadruple the runtime.
MAXDIGITS = 10
+# 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)
+
# ------------------------------------------------------------ utilities
# Use check instead of assert so the test still does something
if not ok:
raise TestFailed, join(map(str, args), " ")
+# 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(ndigits):
+ assert ndigits > 0
+ nbits_hi = ndigits * SHIFT
+ nbits_lo = nbits_hi - SHIFT + 1
+ answer = 0L
+ nbits = 0
+ r = int(random() * (SHIFT * 2)) | 1 # force 1 bits to start
+ while nbits < nbits_lo:
+ bits = (r >> 1) + 1
+ bits = min(bits, nbits_hi - nbits)
+ assert 1 <= bits <= SHIFT
+ nbits = nbits + bits
+ answer = answer << bits
+ if r & 1:
+ answer = answer | ((1 << bits) - 1)
+ r = int(random() * (SHIFT * 2))
+ assert nbits_lo <= nbits <= nbits_hi
+ if 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 getran(ndigits):
+def getran2(ndigits):
answer = 0L
for i in range(ndigits):
answer = (answer << SHIFT) | randint(0, MASK)
# -------------------------------------------------------------- ~ & | ^
def test_bitop_identities_1(x):
+ check(x & 0 == 0, "x & 0 != 0 for", x)
+ check(x | 0 == x, "x | 0 != x for", x)
+ check(x ^ 0 == x, "x ^ 0 != x for", x)
+ check(x & -1 == x, "x & -1 != x for", x)
+ check(x | -1 == -1, "x | -1 != -1 for", x)
+ check(x ^ -1 == ~x, "x ^ -1 != ~x for", x)
check(x == ~~x, "x != ~~x for", x)
check(x & x == x, "x & x != x for", x)
check(x | x == x, "x | x != x for", x)
check(x & ~x == 0, "x & ~x != 0 for", x)
check(x | ~x == -1, "x | ~x != -1 for", x)
check(x ^ ~x == -1, "x ^ ~x != -1 for", x)
- check(-x == 1 + ~x, "-x != 1 + ~x for", x)
- for s in range(2*SHIFT):
- check( ((x >> s) << s) | (x & ((1L << s) - 1)) == x,
- "((x >> s) << s) | (x & ((1L << s) - 1)) != x for",
- x, s)
+ check(-x == 1 + ~x == ~(x-1), "not -x == 1 + ~x == ~(x-1) for", x)
+ for n in range(2*SHIFT):
+ p2 = 2L ** n
+ check(x << n >> n == x, "x << n >> n != x for", x, n)
+ check(x / p2 == x >> n, "x / p2 != x >> n for x n p2", x, n, p2)
+ check(x * p2 == x << n, "x * p2 != x << n for x n p2", x, n, p2)
+ check(x & -p2 == x >> n << n == x & ~(p2 - 1),
+ "not x & -p2 == x >> n << n == x & ~(p2 - 1) for x n p2",
+ x, n, p2)
def test_bitop_identities_2(x, y):
+ check(x & y == y & x, "x & y != y & x for", x, y)
+ check(x | y == y | x, "x | y != y | x for", x, y)
+ check(x ^ y == y ^ x, "x ^ y != y ^ x for", x, y)
+ check(x ^ y ^ x == y, "x ^ y ^ x != y for", x, y)
check(x & y == ~(~x | ~y), "x & y != ~(~x | ~y) for", x, y)
check(x | y == ~(~x & ~y), "x | y != ~(~x & ~y) for", x, y)
check(x ^ y == (x | y) & ~(x & y),
"x ^ y == (x | y) & (~x | ~y) for", x, y)
def test_bitop_identities_3(x, y, z):
+ check((x & y) & z == x & (y & z),
+ "(x & y) & z != x & (y & z) for", x, y, z)
+ check((x | y) | z == x | (y | z),
+ "(x | y) | z != x | (y | z) for", x, y, z)
+ check((x ^ y) ^ z == x ^ (y ^ z),
+ "(x ^ y) ^ z != x ^ (y ^ z) for", x, y, z)
check(x & (y | z) == (x & y) | (x & z),
"x & (y | z) != (x & y) | (x & z) for", x, y, z)
check(x | (y & z) == (x | y) & (x | z),
def test_bitop_identities(maxdigits=MAXDIGITS):
print "long bit-operation identities"
+ for x in special:
+ test_bitop_identities_1(x)
digits = range(1, maxdigits+1)
for lenx in digits:
x = getran(lenx)
test_bitop_identities_2(x, y)
test_bitop_identities_3(x, y, getran((lenx + leny)/2))
-# ---------------------------------------------------------- hex oct str
+# ------------------------------------------------------ hex oct str atol
def slow_format(x, base):
if (x, base) == (0, 8):
sign = 0
if x < 0:
sign, x = 1, -x
- marks = "0123456789ABCDEF"
while x:
x, r = divmod(x, base)
digits.append(int(r))
digits.reverse()
digits = digits or [0]
- return ['', '-'][sign] + \
+ return '-'[:sign] + \
{8: '0', 10: '', 16: '0x'}[base] + \
- join(map(lambda i, marks=marks: marks[i], digits), '') + \
+ join(map(lambda i: "0123456789ABCDEF"[i], digits), '') + \
"L"
def test_format_1(x):
+ from string import atol
for base, mapper in (8, oct), (10, str), (16, hex):
got = mapper(x)
expected = slow_format(x, base)
check(got == expected, mapper.__name__, "returned",
got, "but expected", expected, "for", x)
+ check(atol(got, 0) == x, 'atol("%s", 0) !=' % got, x)
def test_format(maxdigits=MAXDIGITS):
- print "long str/hex/oct"
+ print "long str/hex/oct/atol"
+ for x in special:
+ test_format_1(x)
for i in range(10):
for lenx in range(1, maxdigits+1):
x = getran(lenx)
test_format_1(x)
+# ----------------------------------------------------------------- misc
+
+def test_misc(maxdigits=MAXDIGITS):
+ print "long miscellaneous operations"
+ import sys
+
+ # check the extremes in int<->long conversion
+ hugepos = sys.maxint
+ hugeneg = -hugepos - 1
+ hugepos_aslong = long(hugepos)
+ hugeneg_aslong = long(hugeneg)
+ check(hugepos == hugepos_aslong, "long(sys.maxint) != sys.maxint")
+ check(hugeneg == hugeneg_aslong,
+ "long(-sys.maxint-1) != -sys.maxint-1")
+
+ # long -> int should not fail for hugepos_aslong or hugeneg_aslong
+ try:
+ check(int(hugepos_aslong) == hugepos,
+ "converting sys.maxint to long and back to int fails")
+ except OverflowError:
+ raise TestFailed, "int(long(sys.maxint)) overflowed!"
+ try:
+ check(int(hugeneg_aslong) == hugeneg,
+ "converting -sys.maxint-1 to long and back to int fails")
+ except OverflowError:
+ raise TestFailed, "int(long(-sys.maxint-1)) overflowed!"
+
+ # but long -> int should overflow for hugepos+1 and hugeneg-1
+ x = hugepos_aslong + 1
+ try:
+ int(x)
+ raise ValueError
+ except OverflowError:
+ pass
+ except:
+ raise TestFailed, "int(long(sys.maxint) + 1) didn't overflow"
+
+ x = hugeneg_aslong - 1
+ try:
+ int(x)
+ raise ValueError
+ except OverflowError:
+ pass
+ except:
+ raise TestFailed, "int(long(-sys.maxint-1) - 1) didn't overflow"
+
# ---------------------------------------------------------------- do it
test_division()
test_bitop_identities()
test_format()
+test_misc()
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