view contrib/perf.py @ 15462:2b1ec74c961f stable

mdiff/patch: fix bad hunk handling for unified diffs with zero context

Prior to this patch "hg diff -U0", i.e., zero lines of context, would
output hunk headers with a start line one greater than what GNU patch
and git output. Guido van Rossum documents the unified diff format[1]
as having a start line value "one lower than one would expect" for
zero length hunks.

Comparing the behaviour of the three systems prior to this patch in
transforming

  c1
  c3

to

  c1
  c2
  c3

- GNU "diff -U0" reports the hunk as "@@ -1,0 +2 @@"
- "git diff -U0" reports the hunk as "@@ -1,0 +2 @@"
- "hg diff -U0" reports the hunk as "@@ -2,0 +2,1 @@"

After this patch, "hg diff -U0" reports "@@ -1,0 +2,1 @@".

Since "hg export --config diff.unified=0" outputs zero-context unified
diffs, "hg import" has also been updated to account for start lines
one less than expected for zero length hunk ranges.

[1]: http://www.artima.com/weblogs/viewpost.jsp?thread=164293

# perf.py - performance test routines
'''helper extension to measure performance'''

from mercurial import cmdutil, scmutil, match, commands
import time, os, sys

def timer(func, title=None):
    results = []
    begin = time.time()
    count = 0
    while True:
        ostart = os.times()
        cstart = time.time()
        r = func()
        cstop = time.time()
        ostop = os.times()
        count += 1
        a, b = ostart, ostop
        results.append((cstop - cstart, b[0] - a[0], b[1]-a[1]))
        if cstop - begin > 3 and count >= 100:
            break
        if cstop - begin > 10 and count >= 3:
            break
    if title:
        sys.stderr.write("! %s\n" % title)
    if r:
        sys.stderr.write("! result: %s\n" % r)
    m = min(results)
    sys.stderr.write("! wall %f comb %f user %f sys %f (best of %d)\n"
                     % (m[0], m[1] + m[2], m[1], m[2], count))

def perfwalk(ui, repo, *pats):
    try:
        m = scmutil.match(repo[None], pats, {})
        timer(lambda: len(list(repo.dirstate.walk(m, [], True, False))))
    except:
        try:
            m = scmutil.match(repo[None], pats, {})
            timer(lambda: len([b for a, b, c in repo.dirstate.statwalk([], m)]))
        except:
            timer(lambda: len(list(cmdutil.walk(repo, pats, {}))))

def perfstatus(ui, repo, *pats):
    #m = match.always(repo.root, repo.getcwd())
    #timer(lambda: sum(map(len, repo.dirstate.status(m, [], False, False, False))))
    timer(lambda: sum(map(len, repo.status())))

def perfheads(ui, repo):
    timer(lambda: len(repo.changelog.heads()))

def perftags(ui, repo):
    import mercurial.changelog, mercurial.manifest
    def t():
        repo.changelog = mercurial.changelog.changelog(repo.sopener)
        repo.manifest = mercurial.manifest.manifest(repo.sopener)
        repo._tags = None
        return len(repo.tags())
    timer(t)

def perfdirstate(ui, repo):
    "a" in repo.dirstate
    def d():
        repo.dirstate.invalidate()
        "a" in repo.dirstate
    timer(d)

def perfdirstatedirs(ui, repo):
    "a" in repo.dirstate
    def d():
        "a" in repo.dirstate._dirs
        del repo.dirstate._dirs
    timer(d)

def perfmanifest(ui, repo):
    def d():
        t = repo.manifest.tip()
        m = repo.manifest.read(t)
        repo.manifest.mapcache = None
        repo.manifest._cache = None
    timer(d)

def perfindex(ui, repo):
    import mercurial.revlog
    mercurial.revlog._prereadsize = 2**24 # disable lazy parser in old hg
    n = repo["tip"].node()
    def d():
        repo.invalidate()
        repo[n]
    timer(d)

def perfstartup(ui, repo):
    cmd = sys.argv[0]
    def d():
        os.system("HGRCPATH= %s version -q > /dev/null" % cmd)
    timer(d)

def perfparents(ui, repo):
    nl = [repo.changelog.node(i) for i in xrange(1000)]
    def d():
        for n in nl:
            repo.changelog.parents(n)
    timer(d)

def perflookup(ui, repo, rev):
    timer(lambda: len(repo.lookup(rev)))

def perflog(ui, repo, **opts):
    ui.pushbuffer()
    timer(lambda: commands.log(ui, repo, rev=[], date='', user='',
                               copies=opts.get('rename')))
    ui.popbuffer()

def perftemplating(ui, repo):
    ui.pushbuffer()
    timer(lambda: commands.log(ui, repo, rev=[], date='', user='',
                               template='{date|shortdate} [{rev}:{node|short}]'
                               ' {author|person}: {desc|firstline}\n'))
    ui.popbuffer()

def perfdiffwd(ui, repo):
    """Profile diff of working directory changes"""
    options = {
        'w': 'ignore_all_space',
        'b': 'ignore_space_change',
        'B': 'ignore_blank_lines',
        }

    for diffopt in ('', 'w', 'b', 'B', 'wB'):
        opts = dict((options[c], '1') for c in diffopt)
        def d():
            ui.pushbuffer()
            commands.diff(ui, repo, **opts)
            ui.popbuffer()
        title = 'diffopts: %s' % (diffopt and ('-' + diffopt) or 'none')
        timer(d, title)

def perfrevlog(ui, repo, file_, **opts):
    from mercurial import revlog
    dist = opts['dist']
    def d():
        r = revlog.revlog(lambda fn: open(fn, 'rb'), file_)
        for x in xrange(0, len(r), dist):
            r.revision(r.node(x))

    timer(d)

cmdtable = {
    'perflookup': (perflookup, []),
    'perfparents': (perfparents, []),
    'perfstartup': (perfstartup, []),
    'perfstatus': (perfstatus, []),
    'perfwalk': (perfwalk, []),
    'perfmanifest': (perfmanifest, []),
    'perfindex': (perfindex, []),
    'perfheads': (perfheads, []),
    'perftags': (perftags, []),
    'perfdirstate': (perfdirstate, []),
    'perfdirstatedirs': (perfdirstate, []),
    'perflog': (perflog,
                [('', 'rename', False, 'ask log to follow renames')]),
    'perftemplating': (perftemplating, []),
    'perfdiffwd': (perfdiffwd, []),
    'perfrevlog': (perfrevlog,
                   [('d', 'dist', 100, 'distance between the revisions')],
                   "[INDEXFILE]"),
}