# mdiff.py - diff and patch routines for mercurial
#
# Copyright 2005 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.
from demandload import demandload
import bdiff, mpatch
demandload(globals(), "re struct util")
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
def unidiff(a, ad, b, bd, fn, r=None, text=False,
showfunc=False, ignorews=False, ignorewsamount=False,
ignoreblanklines=False):
if not a and not b: return ""
epoch = util.datestr((0, 0))
if not text and (util.binary(a) or util.binary(b)):
l = ['Binary file %s has changed\n' % fn]
elif not a:
b = splitnewlines(b)
if a is None:
l1 = "--- %s\t%s\n" % ("/dev/null", epoch)
else:
l1 = "--- %s\t%s\n" % ("a/" + fn, ad)
l2 = "+++ %s\t%s\n" % ("b/" + fn, 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\t%s\n" % ("a/" + fn, ad)
if b is None:
l2 = "+++ %s\t%s\n" % ("/dev/null", epoch)
else:
l2 = "+++ %s\t%s\n" % ("b/" + fn, 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,
showfunc=showfunc, ignorews=ignorews,
ignorewsamount=ignorewsamount,
ignoreblanklines=ignoreblanklines))
if not l: return ""
# difflib uses a space, rather than a tab
l[0] = "%s\t%s\n" % (l[0][:-2], ad)
l[1] = "%s\t%s\n" % (l[1][:-2], 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
# context is the number of context lines
# showfunc enables diff -p output
# ignorews ignores all whitespace changes in the diff
# ignorewsamount ignores changes in the amount of whitespace
# ignoreblanklines ignores changes whose lines are all blank
def bunidiff(t1, t2, l1, l2, header1, header2, context=3, showfunc=False,
ignorews=False, ignorewsamount=False, ignoreblanklines=False):
def contextend(l, len):
ret = l + context
if ret > len:
ret = len
return ret
def contextstart(l):
ret = l - 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 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 showfunc:
funcre = re.compile('\w')
if ignorewsamount:
wsamountre = re.compile('[ \t]+')
wsappendedre = re.compile(' \n')
if ignoreblanklines:
wsblanklinesre = re.compile('\n')
if ignorews:
wsre = re.compile('[ \t]')
# 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 ignoreblanklines:
wsold = wsblanklinesre.sub('', "".join(old))
wsnew = wsblanklinesre.sub('', "".join(new))
if wsold == wsnew:
continue
if ignorewsamount:
wsold = wsamountre.sub(' ', "".join(old))
wsold = wsappendedre.sub('\n', wsold)
wsnew = wsamountre.sub(' ', "".join(new))
wsnew = wsappendedre.sub('\n', wsnew)
if wsold == wsnew:
continue
if ignorews:
wsold = wsre.sub('', "".join(old))
wsnew = wsre.sub('', "".join(new))
if wsold == wsnew:
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] + 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])
patches = mpatch.patches
patchedsize = mpatch.patchedsize
textdiff = bdiff.bdiff