Mercurial > hg
view tests/test-pathencode.py @ 34682:7e3001b74ab3
tersestatus: re-implement the functionality to terse the status
The previous terse status implementation was hacking around os.listdir() and was
flaky. There have been a lot of instances of mercurial buildbots failing
and google's internal builds failing because of the
hacky implementation of terse status. Even though I wrote the last
implementation but it was hard for me to find the reason for the flake.
The new implementation can be slower than the old one but is clean and easy to
understand.
In this we create a node object for each directory and create a tree
like structure starting from the root of the working copy. While building the
tree like structure we store some information on the nodes which will be helpful
for deciding later whether we can terse the dir or not.
Once the whole tree is build we traverse and built the list of files for each
status with required tersing.
There is no behaviour change as the old test, test-status-terse.t passes with
the new implementation.
Differential Revision: https://phab.mercurial-scm.org/D985
author | Pulkit Goyal <7895pulkit@gmail.com> |
---|---|
date | Fri, 06 Oct 2017 20:54:23 +0530 |
parents | d43340bec0f5 |
children | 58c1368ab629 |
line wrap: on
line source
# This is a randomized test that generates different pathnames every # time it is invoked, and tests the encoding of those pathnames. # # It uses a simple probabilistic model to generate valid pathnames # that have proven likely to expose bugs and divergent behavior in # different encoding implementations. from __future__ import absolute_import, print_function import binascii import collections import itertools import math import os import random import sys import time from mercurial import ( store, ) try: xrange except NameError: xrange = range validchars = set(map(chr, range(0, 256))) alphanum = range(ord('A'), ord('Z')) for c in '\0/': validchars.remove(c) winreserved = ('aux con prn nul'.split() + ['com%d' % i for i in xrange(1, 10)] + ['lpt%d' % i for i in xrange(1, 10)]) def casecombinations(names): '''Build all case-diddled combinations of names.''' combos = set() for r in names: for i in xrange(len(r) + 1): for c in itertools.combinations(xrange(len(r)), i): d = r for j in c: d = ''.join((d[:j], d[j].upper(), d[j + 1:])) combos.add(d) return sorted(combos) def buildprobtable(fp, cmd='hg manifest tip'): '''Construct and print a table of probabilities for path name components. The numbers are percentages.''' counts = collections.defaultdict(lambda: 0) for line in os.popen(cmd).read().splitlines(): if line[-2:] in ('.i', '.d'): line = line[:-2] if line.startswith('data/'): line = line[5:] for c in line: counts[c] += 1 for c in '\r/\n': counts.pop(c, None) t = sum(counts.itervalues()) / 100.0 fp.write('probtable = (') for i, (k, v) in enumerate(sorted(counts.iteritems(), key=lambda x: x[1], reverse=True)): if (i % 5) == 0: fp.write('\n ') vt = v / t if vt < 0.0005: break fp.write('(%r, %.03f), ' % (k, vt)) fp.write('\n )\n') # A table of character frequencies (as percentages), gleaned by # looking at filelog names from a real-world, very large repo. probtable = ( ('t', 9.828), ('e', 9.042), ('s', 8.011), ('a', 6.801), ('i', 6.618), ('g', 5.053), ('r', 5.030), ('o', 4.887), ('p', 4.363), ('n', 4.258), ('l', 3.830), ('h', 3.693), ('_', 3.659), ('.', 3.377), ('m', 3.194), ('u', 2.364), ('d', 2.296), ('c', 2.163), ('b', 1.739), ('f', 1.625), ('6', 0.666), ('j', 0.610), ('y', 0.554), ('x', 0.487), ('w', 0.477), ('k', 0.476), ('v', 0.473), ('3', 0.336), ('1', 0.335), ('2', 0.326), ('4', 0.310), ('5', 0.305), ('9', 0.302), ('8', 0.300), ('7', 0.299), ('q', 0.298), ('0', 0.250), ('z', 0.223), ('-', 0.118), ('C', 0.095), ('T', 0.087), ('F', 0.085), ('B', 0.077), ('S', 0.076), ('P', 0.076), ('L', 0.059), ('A', 0.058), ('N', 0.051), ('D', 0.049), ('M', 0.046), ('E', 0.039), ('I', 0.035), ('R', 0.035), ('G', 0.028), ('U', 0.026), ('W', 0.025), ('O', 0.017), ('V', 0.015), ('H', 0.013), ('Q', 0.011), ('J', 0.007), ('K', 0.005), ('+', 0.004), ('X', 0.003), ('Y', 0.001), ) for c, _ in probtable: validchars.remove(c) validchars = list(validchars) def pickfrom(rng, table): c = 0 r = rng.random() * sum(i[1] for i in table) for i, p in table: c += p if c >= r: return i reservedcombos = casecombinations(winreserved) # The first component of a name following a slash. firsttable = ( (lambda rng: pickfrom(rng, probtable), 90), (lambda rng: rng.choice(validchars), 5), (lambda rng: rng.choice(reservedcombos), 5), ) # Components of a name following the first. resttable = firsttable[:-1] # Special suffixes. internalsuffixcombos = casecombinations('.hg .i .d'.split()) # The last component of a path, before a slash or at the end of a name. lasttable = resttable + ( (lambda rng: '', 95), (lambda rng: rng.choice(internalsuffixcombos), 5), ) def makepart(rng, k): '''Construct a part of a pathname, without slashes.''' p = pickfrom(rng, firsttable)(rng) l = len(p) ps = [p] maxl = rng.randint(1, k) while l < maxl: p = pickfrom(rng, resttable)(rng) l += len(p) ps.append(p) ps.append(pickfrom(rng, lasttable)(rng)) return ''.join(ps) def makepath(rng, j, k): '''Construct a complete pathname.''' return ('data/' + '/'.join(makepart(rng, k) for _ in xrange(j)) + rng.choice(['.d', '.i'])) def genpath(rng, count): '''Generate random pathnames with gradually increasing lengths.''' mink, maxk = 1, 4096 def steps(): for i in xrange(count): yield mink + int(round(math.sqrt((maxk - mink) * float(i) / count))) for k in steps(): x = rng.randint(1, k) y = rng.randint(1, k) yield makepath(rng, x, y) def runtests(rng, seed, count): nerrs = 0 for p in genpath(rng, count): h = store._pathencode(p) # uses C implementation, if available r = store._hybridencode(p, True) # reference implementation in Python if h != r: if nerrs == 0: print('seed:', hex(seed)[:-1], file=sys.stderr) print("\np: '%s'" % p.encode("string_escape"), file=sys.stderr) print("h: '%s'" % h.encode("string_escape"), file=sys.stderr) print("r: '%s'" % r.encode("string_escape"), file=sys.stderr) nerrs += 1 return nerrs def main(): import getopt # Empirically observed to take about a second to run count = 100 seed = None opts, args = getopt.getopt(sys.argv[1:], 'c:s:', ['build', 'count=', 'seed=']) for o, a in opts: if o in ('-c', '--count'): count = int(a) elif o in ('-s', '--seed'): seed = int(a, base=0) # accepts base 10 or 16 strings elif o == '--build': buildprobtable(sys.stdout, 'find .hg/store/data -type f && ' 'cat .hg/store/fncache 2>/dev/null') sys.exit(0) if seed is None: try: seed = int(binascii.hexlify(os.urandom(16)), 16) except AttributeError: seed = int(time.time() * 1000) rng = random.Random(seed) if runtests(rng, seed, count): sys.exit(1) if __name__ == '__main__': main()