Mercurial > hg > mercurial-crew-with-dirclash
view mercurial/mdiff.py @ 5378:8a2915f57dfc
convert: add a mode where mercurial_sink skips empty revisions.
The getchanges function of some converter_source classes can return
some false positives. I.e. they sometimes claim that a file "foo"
was changed in some revision, even though its contents are still the
same.
convert_svn is particularly bad, but I think this can also happen with
convert_cvs and, at least in theory, with mercurial_source.
For regular conversions this is not really a problem - as long as
getfile returns the right contents, we'll get a converted revision
with the right contents. But when we use --filemap, this could lead
to superfluous revisions being converted.
Instead of fixing every converter_source, I decided to change
mercurial_sink to work around this problem.
When --filemap is used, we're interested only in revisions that touch
some specific files. If a revision doesn't change any of these files,
then we're not interested in it (at least for revisions with a single
parent; merges are special).
For mercurial_sink, we abuse this property and rollback a commit if
the manifest text hasn't changed. This avoids duplicating the logic
from localrepo.filecommit to detect unchanged files.
author | Alexis S. L. Carvalho <alexis@cecm.usp.br> |
---|---|
date | Thu, 04 Oct 2007 23:21:37 -0300 |
parents | 7530334bf301 |
children |
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# mdiff.py - diff and patch routines for mercurial # # Copyright 2005, 2006 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms # of the GNU General Public License, incorporated herein by reference. import bdiff, mpatch, re, struct, util, md5 def splitnewlines(text): '''like str.splitlines, but only split on newlines.''' lines = [l + '\n' for l in text.split('\n')] if lines: if lines[-1] == '\n': lines.pop() else: lines[-1] = lines[-1][:-1] return lines class diffopts(object): '''context is the number of context lines text treats all files as text showfunc enables diff -p output git enables the git extended patch format nodates removes dates from diff headers ignorews ignores all whitespace changes in the diff ignorewsamount ignores changes in the amount of whitespace ignoreblanklines ignores changes whose lines are all blank''' defaults = { 'context': 3, 'text': False, 'showfunc': True, 'git': False, 'nodates': False, 'ignorews': False, 'ignorewsamount': False, 'ignoreblanklines': False, } __slots__ = defaults.keys() def __init__(self, **opts): for k in self.__slots__: v = opts.get(k) if v is None: v = self.defaults[k] setattr(self, k, v) defaultopts = diffopts() def wsclean(opts, text): if opts.ignorews: text = re.sub('[ \t]+', '', text) elif opts.ignorewsamount: text = re.sub('[ \t]+', ' ', text) text = re.sub('[ \t]+\n', '\n', text) if opts.ignoreblanklines: text = re.sub('\n+', '', text) return text def unidiff(a, ad, b, bd, fn, r=None, opts=defaultopts): def datetag(date, addtab=True): if not opts.git and not opts.nodates: return '\t%s\n' % date if addtab and ' ' in fn: return '\t\n' return '\n' if not a and not b: return "" epoch = util.datestr((0, 0)) if not opts.text and (util.binary(a) or util.binary(b)): def h(v): # md5 is used instead of sha1 because md5 is supposedly faster return md5.new(v).digest() if a and b and len(a) == len(b) and h(a) == h(b): return "" l = ['Binary file %s has changed\n' % fn] elif not a: b = splitnewlines(b) if a is None: l1 = '--- /dev/null%s' % datetag(epoch, False) else: l1 = "--- %s%s" % ("a/" + fn, datetag(ad)) l2 = "+++ %s%s" % ("b/" + fn, datetag(bd)) l3 = "@@ -0,0 +1,%d @@\n" % len(b) l = [l1, l2, l3] + ["+" + e for e in b] elif not b: a = splitnewlines(a) l1 = "--- %s%s" % ("a/" + fn, datetag(ad)) if b is None: l2 = '+++ /dev/null%s' % datetag(epoch, False) else: l2 = "+++ %s%s" % ("b/" + fn, datetag(bd)) l3 = "@@ -1,%d +0,0 @@\n" % len(a) l = [l1, l2, l3] + ["-" + e for e in a] else: al = splitnewlines(a) bl = splitnewlines(b) l = list(bunidiff(a, b, al, bl, "a/" + fn, "b/" + fn, opts=opts)) if not l: return "" # difflib uses a space, rather than a tab l[0] = "%s%s" % (l[0][:-2], datetag(ad)) l[1] = "%s%s" % (l[1][:-2], datetag(bd)) for ln in xrange(len(l)): if l[ln][-1] != '\n': l[ln] += "\n\ No newline at end of file\n" if r: l.insert(0, "diff %s %s\n" % (' '.join(["-r %s" % rev for rev in r]), fn)) return "".join(l) # somewhat self contained replacement for difflib.unified_diff # t1 and t2 are the text to be diffed # l1 and l2 are the text broken up into lines # header1 and header2 are the filenames for the diff output def bunidiff(t1, t2, l1, l2, header1, header2, opts=defaultopts): def contextend(l, len): ret = l + opts.context if ret > len: ret = len return ret def contextstart(l): ret = l - opts.context if ret < 0: return 0 return ret def yieldhunk(hunk, header): if header: for x in header: yield x (astart, a2, bstart, b2, delta) = hunk aend = contextend(a2, len(l1)) alen = aend - astart blen = b2 - bstart + aend - a2 func = "" if opts.showfunc: # walk backwards from the start of the context # to find a line starting with an alphanumeric char. for x in xrange(astart, -1, -1): t = l1[x].rstrip() if funcre.match(t): func = ' ' + t[:40] break yield "@@ -%d,%d +%d,%d @@%s\n" % (astart + 1, alen, bstart + 1, blen, func) for x in delta: yield x for x in xrange(a2, aend): yield ' ' + l1[x] header = [ "--- %s\t\n" % header1, "+++ %s\t\n" % header2 ] if opts.showfunc: funcre = re.compile('\w') # bdiff.blocks gives us the matching sequences in the files. The loop # below finds the spaces between those matching sequences and translates # them into diff output. # diff = bdiff.blocks(t1, t2) hunk = None for i in xrange(len(diff)): # The first match is special. # we've either found a match starting at line 0 or a match later # in the file. If it starts later, old and new below will both be # empty and we'll continue to the next match. if i > 0: s = diff[i-1] else: s = [0, 0, 0, 0] delta = [] s1 = diff[i] a1 = s[1] a2 = s1[0] b1 = s[3] b2 = s1[2] old = l1[a1:a2] new = l2[b1:b2] # bdiff sometimes gives huge matches past eof, this check eats them, # and deals with the special first match case described above if not old and not new: continue if opts.ignorews or opts.ignorewsamount or opts.ignoreblanklines: if wsclean(opts, "".join(old)) == wsclean(opts, "".join(new)): continue astart = contextstart(a1) bstart = contextstart(b1) prev = None if hunk: # join with the previous hunk if it falls inside the context if astart < hunk[1] + opts.context + 1: prev = hunk astart = hunk[1] bstart = hunk[3] else: for x in yieldhunk(hunk, header): yield x # we only want to yield the header if the files differ, and # we only want to yield it once. header = None if prev: # we've joined the previous hunk, record the new ending points. hunk[1] = a2 hunk[3] = b2 delta = hunk[4] else: # create a new hunk hunk = [ astart, a2, bstart, b2, delta ] delta[len(delta):] = [ ' ' + x for x in l1[astart:a1] ] delta[len(delta):] = [ '-' + x for x in old ] delta[len(delta):] = [ '+' + x for x in new ] if hunk: for x in yieldhunk(hunk, header): yield x def patchtext(bin): pos = 0 t = [] while pos < len(bin): p1, p2, l = struct.unpack(">lll", bin[pos:pos + 12]) pos += 12 t.append(bin[pos:pos + l]) pos += l return "".join(t) def patch(a, bin): return mpatch.patches(a, [bin]) # similar to difflib.SequenceMatcher.get_matching_blocks def get_matching_blocks(a, b): return [(d[0], d[2], d[1] - d[0]) for d in bdiff.blocks(a, b)] def trivialdiffheader(length): return struct.pack(">lll", 0, 0, length) patches = mpatch.patches patchedsize = mpatch.patchedsize textdiff = bdiff.bdiff