test.lua

-- bitlib test suite
-- (c) Reuben Thomas 2007-2008 and Shmuel Zeigerman 2007
-- See README for license

-- FIXME: These settings should really be in the callee, but shake
-- doesn't support that.
-- FIXME: Setting of package.cpath only works because LD_LIBRARY_PATH
-- contains only a single directory in this case
package.path = ""
package.cpath = (os.getenv ("LD_LIBRARY_PATH") or ".") .. "/?.so"

require "bit"


print ("bit.bits = " .. bit.bits)

assert (bit.band (0, 0) == bit.cast (0))
assert (bit.band (0, -1) == bit.cast (0))
assert (bit.band (-1, -1) == bit.cast (-1))

assert (bit.bor  (0, 0) == bit.cast (0))
assert (bit.bor  (0, -1) == bit.cast (-1))
assert (bit.bor  (-1, -1) == bit.cast (-1))

assert (bit.bxor (0, 0) == bit.cast (0))
assert (bit.bxor (0, -1) == bit.cast (-1))
assert (bit.bxor (-1, -1) == bit.cast (0))

assert (bit.bnot (0) == bit.cast (-1))
assert (bit.bnot (-1) == bit.cast (0))

assert (bit.lshift (0, 0) == bit.cast (0))
assert (bit.lshift (-1, 0) == bit.cast (-1))

assert (bit.rshift (0, 0) == bit.cast (0))
assert (bit.rshift (-1, 0) == bit.cast (-1))

for nb = 1, bit.bits do
  local a = 2 ^ nb - 1
  print ("nb = " .. nb .. ", a = " .. a)
  assert (bit.band (a, 0)  == bit.cast (0))
  assert (bit.band (a, 1)  == bit.cast (1))
  assert (bit.band (a, -1) == bit.cast (a))
  assert (bit.band (a, a)  == bit.cast (a))

  assert (bit.bor (a, 0)  == bit.cast (a))
  assert (bit.bor (a, 1)  == bit.cast (a))
  assert (bit.bor (a, -1) == bit.cast (-1))
  assert (bit.bor (a, a)  == bit.cast (a))

  assert (bit.bxor (a, 0)  == bit.cast (a))
  assert (bit.bxor (a, 1)  == bit.cast (a - 1))
  assert (bit.bxor (a, -1) == bit.cast (-a - 1))
  assert (bit.bxor (a, a)  == bit.cast (0))

  assert (bit.bnot (a) == bit.cast (-1 - a))

  if nb < bit.bits then
    assert (bit.lshift (a, 1) == bit.cast (a + a))
    assert (bit.lshift (1, nb) == bit.cast (2 ^ nb))
  end

  assert (bit.rshift (a, 1) == math.floor (a / 2))
  if nb < bit.bits then
    assert (bit.rshift (a, nb) == bit.cast (0))
  end
  assert (bit.rshift (a, nb - 1) == bit.cast (1))

  assert (bit.arshift (-1, 1) == bit.cast (-1))
end

print "All bitlib tests passed"