rust: translation of missingancestors
This is as direct as possible a translation of the ancestor.missingancestors
Python class in pure Rust. The goal for this changeset is to make it easy
to compare with the Python version.
We also add to Python tests the cases that helped us develop and debug
this implementation.
Some possible optimizations are marked along the way as TODO comments
Differential Revision: https://phab.mercurial-scm.org/D5416
# Randomized torture test generation for bdiff
from __future__ import absolute_import, print_function
import random
import sys
from mercurial import (
mdiff,
)
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 = mdiff.textdiff(a, b)
if not d:
raise ValueError("empty")
c = mdiff.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