contrib/synthrepo.py
author Gregory Szorc <gregory.szorc@gmail.com>
Sat, 05 Dec 2015 21:11:04 -0800
changeset 27266 4dccc37b87bd
parent 26587 56b2bcea2529
child 28563 62250a48dc7f
permissions -rw-r--r--
ui: support declaring path push urls as sub-options Power users often want to apply per-path configuration options. For example, they may want to declare an alternate URL for push operations or declare a revset of revisions to push when `hg push` is used (as opposed to attempting to push all revisions by default). This patch establishes the use of sub-options (config options with ":" in the name) to declare additional behavior for paths. New sub-options are declared by using the new ``@ui.pathsuboption`` decorator. This decorator serves multiple purposes: * Declaring which sub-options are registered * Declaring how a sub-option maps to an attribute on ``path`` instances (this is needed to `hg paths` can render sub-options and values properly) * Validation and normalization of config options to attribute values * Allows extensions to declare new sub-options without monkeypatching * Allows extensions to overwrite built-in behavior for sub-option handling As convenient as the new option registration decorator is, extensions (and even core functionality) may still need an additional hook point to perform finalization of path instances. For example, they may wish to validate that multiple options/attributes aren't conflicting with each other. This hook point could be added later, if needed. To prove this new functionality works, we implement the "pushurl" path sub-option. This option declares the URL that `hg push` should use by default. We require that "pushurl" is an actual URL. This requirement might be controversial and could be dropped if there is opposition. However, objectors should read the complicated code in ui.path.__init__ and commands.push for resolving non-URL values before making a judgement. We also don't allow #fragment in the URLs. I intend to introduce a ":pushrev" (or similar) option to define a revset to control which revisions are pushed when "-r <rev>" isn't passed into `hg push`. This is much more powerful than #fragment and I don't think #fragment is useful enough to continue supporting. The [paths] section of the "config" help page has been updated significantly. `hg paths` has been taught to display path sub-options. The docs mention that "default-push" is now deprecated. However, there are several references to it that need to be cleaned up. A large part of this is converting more consumers to the new paths API. This will happen naturally as more path sub-options are added and more and more components need to access them.

# synthrepo.py - repo synthesis
#
# Copyright 2012 Facebook
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''synthesize structurally interesting change history

This extension is useful for creating a repository with properties
that are statistically similar to an existing repository. During
analysis, a simple probability table is constructed from the history
of an existing repository.  During synthesis, these properties are
reconstructed.

Properties that are analyzed and synthesized include the following:

- Lines added or removed when an existing file is modified
- Number and sizes of files added
- Number of files removed
- Line lengths
- Topological distance to parent changeset(s)
- Probability of a commit being a merge
- Probability of a newly added file being added to a new directory
- Interarrival time, and time zone, of commits
- Number of files in each directory

A few obvious properties that are not currently handled realistically:

- Merges are treated as regular commits with two parents, which is not
  realistic
- Modifications are not treated as operations on hunks of lines, but
  as insertions and deletions of randomly chosen single lines
- Committer ID (always random)
- Executability of files
- Symlinks and binary files are ignored
'''

import bisect, collections, itertools, json, os, random, time, sys
from mercurial import cmdutil, context, patch, scmutil, util, hg, error
from mercurial.i18n import _
from mercurial.node import nullrev, nullid, short

# Note for extension authors: ONLY specify testedwith = 'internal' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'internal'

cmdtable = {}
command = cmdutil.command(cmdtable)

newfile = set(('new fi', 'rename', 'copy f', 'copy t'))

def zerodict():
    return collections.defaultdict(lambda: 0)

def roundto(x, k):
    if x > k * 2:
        return int(round(x / float(k)) * k)
    return int(round(x))

def parsegitdiff(lines):
    filename, mar, lineadd, lineremove = None, None, zerodict(), 0
    binary = False
    for line in lines:
        start = line[:6]
        if start == 'diff -':
            if filename:
                yield filename, mar, lineadd, lineremove, binary
            mar, lineadd, lineremove, binary = 'm', zerodict(), 0, False
            filename = patch.gitre.match(line).group(1)
        elif start in newfile:
            mar = 'a'
        elif start == 'GIT bi':
            binary = True
        elif start == 'delete':
            mar = 'r'
        elif start:
            s = start[0]
            if s == '-' and not line.startswith('--- '):
                lineremove += 1
            elif s == '+' and not line.startswith('+++ '):
                lineadd[roundto(len(line) - 1, 5)] += 1
    if filename:
        yield filename, mar, lineadd, lineremove, binary

@command('analyze',
         [('o', 'output', '', _('write output to given file'), _('FILE')),
          ('r', 'rev', [], _('analyze specified revisions'), _('REV'))],
         _('hg analyze'), optionalrepo=True)
def analyze(ui, repo, *revs, **opts):
    '''create a simple model of a repository to use for later synthesis

    This command examines every changeset in the given range (or all
    of history if none are specified) and creates a simple statistical
    model of the history of the repository. It also measures the directory
    structure of the repository as checked out.

    The model is written out to a JSON file, and can be used by
    :hg:`synthesize` to create or augment a repository with synthetic
    commits that have a structure that is statistically similar to the
    analyzed repository.
    '''
    root = repo.root
    if not root.endswith(os.path.sep):
        root += os.path.sep

    revs = list(revs)
    revs.extend(opts['rev'])
    if not revs:
        revs = [':']

    output = opts['output']
    if not output:
        output = os.path.basename(root) + '.json'

    if output == '-':
        fp = sys.stdout
    else:
        fp = open(output, 'w')

    # Always obtain file counts of each directory in the given root directory.
    def onerror(e):
        ui.warn(_('error walking directory structure: %s\n') % e)

    dirs = {}
    rootprefixlen = len(root)
    for dirpath, dirnames, filenames in os.walk(root, onerror=onerror):
        dirpathfromroot = dirpath[rootprefixlen:]
        dirs[dirpathfromroot] = len(filenames)
        if '.hg' in dirnames:
            dirnames.remove('.hg')

    lineschanged = zerodict()
    children = zerodict()
    p1distance = zerodict()
    p2distance = zerodict()
    linesinfilesadded = zerodict()
    fileschanged = zerodict()
    filesadded = zerodict()
    filesremoved = zerodict()
    linelengths = zerodict()
    interarrival = zerodict()
    parents = zerodict()
    dirsadded = zerodict()
    tzoffset = zerodict()

    # If a mercurial repo is available, also model the commit history.
    if repo:
        revs = scmutil.revrange(repo, revs)
        revs.sort()

        progress = ui.progress
        _analyzing = _('analyzing')
        _changesets = _('changesets')
        _total = len(revs)

        for i, rev in enumerate(revs):
            progress(_analyzing, i, unit=_changesets, total=_total)
            ctx = repo[rev]
            pl = ctx.parents()
            pctx = pl[0]
            prev = pctx.rev()
            children[prev] += 1
            p1distance[rev - prev] += 1
            parents[len(pl)] += 1
            tzoffset[ctx.date()[1]] += 1
            if len(pl) > 1:
                p2distance[rev - pl[1].rev()] += 1
            if prev == rev - 1:
                lastctx = pctx
            else:
                lastctx = repo[rev - 1]
            if lastctx.rev() != nullrev:
                timedelta = ctx.date()[0] - lastctx.date()[0]
                interarrival[roundto(timedelta, 300)] += 1
            diff = sum((d.splitlines() for d in ctx.diff(pctx, git=True)), [])
            fileadds, diradds, fileremoves, filechanges = 0, 0, 0, 0
            for filename, mar, lineadd, lineremove, isbin in parsegitdiff(diff):
                if isbin:
                    continue
                added = sum(lineadd.itervalues(), 0)
                if mar == 'm':
                    if added and lineremove:
                        lineschanged[roundto(added, 5),
                                     roundto(lineremove, 5)] += 1
                        filechanges += 1
                elif mar == 'a':
                    fileadds += 1
                    if '/' in filename:
                        filedir = filename.rsplit('/', 1)[0]
                        if filedir not in pctx.dirs():
                            diradds += 1
                    linesinfilesadded[roundto(added, 5)] += 1
                elif mar == 'r':
                    fileremoves += 1
                for length, count in lineadd.iteritems():
                    linelengths[length] += count
            fileschanged[filechanges] += 1
            filesadded[fileadds] += 1
            dirsadded[diradds] += 1
            filesremoved[fileremoves] += 1

    invchildren = zerodict()

    for rev, count in children.iteritems():
        invchildren[count] += 1

    if output != '-':
        ui.status(_('writing output to %s\n') % output)

    def pronk(d):
        return sorted(d.iteritems(), key=lambda x: x[1], reverse=True)

    json.dump({'revs': len(revs),
               'initdirs': pronk(dirs),
               'lineschanged': pronk(lineschanged),
               'children': pronk(invchildren),
               'fileschanged': pronk(fileschanged),
               'filesadded': pronk(filesadded),
               'linesinfilesadded': pronk(linesinfilesadded),
               'dirsadded': pronk(dirsadded),
               'filesremoved': pronk(filesremoved),
               'linelengths': pronk(linelengths),
               'parents': pronk(parents),
               'p1distance': pronk(p1distance),
               'p2distance': pronk(p2distance),
               'interarrival': pronk(interarrival),
               'tzoffset': pronk(tzoffset),
               },
              fp)
    fp.close()

@command('synthesize',
         [('c', 'count', 0, _('create given number of commits'), _('COUNT')),
          ('', 'dict', '', _('path to a dictionary of words'), _('FILE')),
          ('', 'initfiles', 0, _('initial file count to create'), _('COUNT'))],
         _('hg synthesize [OPTION].. DESCFILE'))
def synthesize(ui, repo, descpath, **opts):
    '''synthesize commits based on a model of an existing repository

    The model must have been generated by :hg:`analyze`. Commits will
    be generated randomly according to the probabilities described in
    the model. If --initfiles is set, the repository will be seeded with
    the given number files following the modeled repository's directory
    structure.

    When synthesizing new content, commit descriptions, and user
    names, words will be chosen randomly from a dictionary that is
    presumed to contain one word per line. Use --dict to specify the
    path to an alternate dictionary to use.
    '''
    try:
        fp = hg.openpath(ui, descpath)
    except Exception as err:
        raise error.Abort('%s: %s' % (descpath, err[0].strerror))
    desc = json.load(fp)
    fp.close()

    def cdf(l):
        if not l:
            return [], []
        vals, probs = zip(*sorted(l, key=lambda x: x[1], reverse=True))
        t = float(sum(probs, 0))
        s, cdfs = 0, []
        for v in probs:
            s += v
            cdfs.append(s / t)
        return vals, cdfs

    lineschanged = cdf(desc['lineschanged'])
    fileschanged = cdf(desc['fileschanged'])
    filesadded = cdf(desc['filesadded'])
    dirsadded = cdf(desc['dirsadded'])
    filesremoved = cdf(desc['filesremoved'])
    linelengths = cdf(desc['linelengths'])
    parents = cdf(desc['parents'])
    p1distance = cdf(desc['p1distance'])
    p2distance = cdf(desc['p2distance'])
    interarrival = cdf(desc['interarrival'])
    linesinfilesadded = cdf(desc['linesinfilesadded'])
    tzoffset = cdf(desc['tzoffset'])

    dictfile = opts.get('dict') or '/usr/share/dict/words'
    try:
        fp = open(dictfile, 'rU')
    except IOError as err:
        raise error.Abort('%s: %s' % (dictfile, err.strerror))
    words = fp.read().splitlines()
    fp.close()

    initdirs = {}
    if desc['initdirs']:
        for k, v in desc['initdirs']:
            initdirs[k.encode('utf-8').replace('.hg', '_hg')] = v
        initdirs = renamedirs(initdirs, words)
    initdirscdf = cdf(initdirs)

    def pick(cdf):
        return cdf[0][bisect.bisect_left(cdf[1], random.random())]

    def pickpath():
        return os.path.join(pick(initdirscdf), random.choice(words))

    def makeline(minimum=0):
        total = max(minimum, pick(linelengths))
        c, l = 0, []
        while c < total:
            w = random.choice(words)
            c += len(w) + 1
            l.append(w)
        return ' '.join(l)

    wlock = repo.wlock()
    lock = repo.lock()

    nevertouch = set(('.hgsub', '.hgignore', '.hgtags'))

    progress = ui.progress
    _synthesizing = _('synthesizing')
    _files = _('initial files')
    _changesets = _('changesets')

    # Synthesize a single initial revision adding files to the repo according
    # to the modeled directory structure.
    initcount = int(opts['initfiles'])
    if initcount and initdirs:
        pctx = repo[None].parents()[0]
        dirs = set(pctx.dirs())
        files = {}

        def validpath(path):
            # Don't pick filenames which are already directory names.
            if path in dirs:
                return False
            # Don't pick directories which were used as file names.
            while path:
                if path in files:
                    return False
                path = os.path.dirname(path)
            return True

        for i in xrange(0, initcount):
            ui.progress(_synthesizing, i, unit=_files, total=initcount)

            path = pickpath()
            while not validpath(path):
                path = pickpath()
            data = '%s contents\n' % path
            files[path] = context.memfilectx(repo, path, data)
            dir = os.path.dirname(path)
            while dir and dir not in dirs:
                dirs.add(dir)
                dir = os.path.dirname(dir)

        def filectxfn(repo, memctx, path):
            return files[path]

        ui.progress(_synthesizing, None)
        message = 'synthesized wide repo with %d files' % (len(files),)
        mc = context.memctx(repo, [pctx.node(), nullid], message,
                            files.iterkeys(), filectxfn, ui.username(),
                            '%d %d' % util.makedate())
        initnode = mc.commit()
        if ui.debugflag:
            hexfn = hex
        else:
            hexfn = short
        ui.status(_('added commit %s with %d files\n')
                  % (hexfn(initnode), len(files)))

    # Synthesize incremental revisions to the repository, adding repo depth.
    count = int(opts['count'])
    heads = set(map(repo.changelog.rev, repo.heads()))
    for i in xrange(count):
        progress(_synthesizing, i, unit=_changesets, total=count)

        node = repo.changelog.node
        revs = len(repo)

        def pickhead(heads, distance):
            if heads:
                lheads = sorted(heads)
                rev = revs - min(pick(distance), revs)
                if rev < lheads[-1]:
                    rev = lheads[bisect.bisect_left(lheads, rev)]
                else:
                    rev = lheads[-1]
                return rev, node(rev)
            return nullrev, nullid

        r1 = revs - min(pick(p1distance), revs)
        p1 = node(r1)

        # the number of heads will grow without bound if we use a pure
        # model, so artificially constrain their proliferation
        toomanyheads = len(heads) > random.randint(1, 20)
        if p2distance[0] and (pick(parents) == 2 or toomanyheads):
            r2, p2 = pickhead(heads.difference([r1]), p2distance)
        else:
            r2, p2 = nullrev, nullid

        pl = [p1, p2]
        pctx = repo[r1]
        mf = pctx.manifest()
        mfk = mf.keys()
        changes = {}
        if mfk:
            for __ in xrange(pick(fileschanged)):
                for __ in xrange(10):
                    fctx = pctx.filectx(random.choice(mfk))
                    path = fctx.path()
                    if not (path in nevertouch or fctx.isbinary() or
                            'l' in fctx.flags()):
                        break
                lines = fctx.data().splitlines()
                add, remove = pick(lineschanged)
                for __ in xrange(remove):
                    if not lines:
                        break
                    del lines[random.randrange(0, len(lines))]
                for __ in xrange(add):
                    lines.insert(random.randint(0, len(lines)), makeline())
                path = fctx.path()
                changes[path] = context.memfilectx(repo, path,
                                                   '\n'.join(lines) + '\n')
            for __ in xrange(pick(filesremoved)):
                path = random.choice(mfk)
                for __ in xrange(10):
                    path = random.choice(mfk)
                    if path not in changes:
                        changes[path] = None
                        break
        if filesadded:
            dirs = list(pctx.dirs())
            dirs.insert(0, '')
        for __ in xrange(pick(filesadded)):
            pathstr = ''
            while pathstr in dirs:
                path = [random.choice(dirs)]
                if pick(dirsadded):
                    path.append(random.choice(words))
                path.append(random.choice(words))
                pathstr = '/'.join(filter(None, path))
            data = '\n'.join(makeline()
                             for __ in xrange(pick(linesinfilesadded))) + '\n'
            changes[pathstr] = context.memfilectx(repo, pathstr, data)
        def filectxfn(repo, memctx, path):
            return changes[path]
        if not changes:
            continue
        if revs:
            date = repo['tip'].date()[0] + pick(interarrival)
        else:
            date = time.time() - (86400 * count)
        # dates in mercurial must be positive, fit in 32-bit signed integers.
        date = min(0x7fffffff, max(0, date))
        user = random.choice(words) + '@' + random.choice(words)
        mc = context.memctx(repo, pl, makeline(minimum=2),
                            sorted(changes.iterkeys()),
                            filectxfn, user, '%d %d' % (date, pick(tzoffset)))
        newnode = mc.commit()
        heads.add(repo.changelog.rev(newnode))
        heads.discard(r1)
        heads.discard(r2)

    lock.release()
    wlock.release()

def renamedirs(dirs, words):
    '''Randomly rename the directory names in the per-dir file count dict.'''
    wordgen = itertools.cycle(words)
    replacements = {'': ''}
    def rename(dirpath):
        '''Recursively rename the directory and all path prefixes.

        The mapping from path to renamed path is stored for all path prefixes
        as in dynamic programming, ensuring linear runtime and consistent
        renaming regardless of iteration order through the model.
        '''
        if dirpath in replacements:
            return replacements[dirpath]
        head, _ = os.path.split(dirpath)
        if head:
            head = rename(head)
        else:
            head = ''
        renamed = os.path.join(head, wordgen.next())
        replacements[dirpath] = renamed
        return renamed
    result = []
    for dirpath, count in dirs.iteritems():
        result.append([rename(dirpath.lstrip(os.sep)), count])
    return result