view contrib/bdiff-torture.py @ 29019:210bb28ca4fb stable

exewrapper: add .dll to LoadLibrary() argument

LoadLibrary() changes behavior depending on whether the argument
passed to it contains a period. From the MSDN docs:

If no file name extension is specified in the lpFileName parameter,
the default library extension .dll is appended. However, the file name
string can include a trailing point character (.) to indicate that the
module name has no extension. When no path is specified, the function
searches for loaded modules whose base name matches the base name of
the module to be loaded. If the name matches, the load succeeds.
Otherwise, the function searches for the file.

As the subsequent patch will show, some environments on Windows
define their Python library as e.g. "libpython2.7.dll." The existing
code would pass "libpython2.7" into LoadLibrary(). It would assume
"7" was the file extension and look for a "libpython2.dll" to load.

By passing ".dll" into LoadLibrary(), we force it to search for the
exact basename we want, even if it contains a period.

# Randomized torture test generation for bdiff

from __future__ import absolute_import, print_function
import random, sys
from mercurial import (
    bdiff,
    mpatch,
)

def reducetest(a, b):
    tries = 0
    reductions = 0
    print("reducing...")
    while tries < 1000:
        a2 = "\n".join(l for l in a.splitlines()
                       if random.randint(0, 100) > 0) + "\n"
        b2 = "\n".join(l for l in b.splitlines()
                       if random.randint(0, 100) > 0) + "\n"
        if a2 == a and b2 == b:
            continue
        if a2 == b2:
            continue
        tries += 1

        try:
            test1(a, b)
        except Exception as inst:
            reductions += 1
            tries = 0
            a = a2
            b = b2

    print("reduced:", reductions, len(a) + len(b),
          repr(a), repr(b))
    try:
        test1(a, b)
    except Exception as inst:
        print("failed:", inst)

    sys.exit(0)

def test1(a, b):
    d = bdiff.bdiff(a, b)
    if not d:
        raise ValueError("empty")
    c = mpatch.patches(a, [d])
    if c != b:
        raise ValueError("bad")

def testwrap(a, b):
    try:
        test1(a, b)
        return
    except Exception as inst:
        pass
    print("exception:", inst)
    reducetest(a, b)

def test(a, b):
    testwrap(a, b)
    testwrap(b, a)

def rndtest(size, noise):
    a = []
    src = "                aaaaaaaabbbbccd"
    for x in xrange(size):
        a.append(src[random.randint(0, len(src) - 1)])

    while True:
        b = [c for c in a if random.randint(0, 99) > noise]
        b2 = []
        for c in b:
            b2.append(c)
            while random.randint(0, 99) < noise:
                b2.append(src[random.randint(0, len(src) - 1)])
        if b2 != a:
            break

    a = "\n".join(a) + "\n"
    b = "\n".join(b2) + "\n"

    test(a, b)

maxvol = 10000
startsize = 2
while True:
    size = startsize
    count = 0
    while size < maxvol:
        print(size)
        volume = 0
        while volume < maxvol:
            rndtest(size, 2)
            volume += size
            count += 2
        size *= 2
    maxvol *= 4
    startsize *= 4