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Diffstat (limited to 'websdk/mercurial/simplemerge.py')
| -rw-r--r--[l---------] | websdk/mercurial/simplemerge.py | 454 |
1 files changed, 453 insertions, 1 deletions
diff --git a/websdk/mercurial/simplemerge.py b/websdk/mercurial/simplemerge.py index 9c7e7a1..3d63d85 120000..100644 --- a/websdk/mercurial/simplemerge.py +++ b/websdk/mercurial/simplemerge.py @@ -1 +1,453 @@ -/usr/share/pyshared/mercurial/simplemerge.py
\ No newline at end of file +# Copyright (C) 2004, 2005 Canonical Ltd +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +# mbp: "you know that thing where cvs gives you conflict markers?" +# s: "i hate that." + +from i18n import _ +import scmutil, util, mdiff +import sys, os + +class CantReprocessAndShowBase(Exception): + pass + +def intersect(ra, rb): + """Given two ranges return the range where they intersect or None. + + >>> intersect((0, 10), (0, 6)) + (0, 6) + >>> intersect((0, 10), (5, 15)) + (5, 10) + >>> intersect((0, 10), (10, 15)) + >>> intersect((0, 9), (10, 15)) + >>> intersect((0, 9), (7, 15)) + (7, 9) + """ + assert ra[0] <= ra[1] + assert rb[0] <= rb[1] + + sa = max(ra[0], rb[0]) + sb = min(ra[1], rb[1]) + if sa < sb: + return sa, sb + else: + return None + +def compare_range(a, astart, aend, b, bstart, bend): + """Compare a[astart:aend] == b[bstart:bend], without slicing. + """ + if (aend - astart) != (bend - bstart): + return False + for ia, ib in zip(xrange(astart, aend), xrange(bstart, bend)): + if a[ia] != b[ib]: + return False + else: + return True + +class Merge3Text(object): + """3-way merge of texts. + + Given strings BASE, OTHER, THIS, tries to produce a combined text + incorporating the changes from both BASE->OTHER and BASE->THIS.""" + def __init__(self, basetext, atext, btext, base=None, a=None, b=None): + self.basetext = basetext + self.atext = atext + self.btext = btext + if base is None: + base = mdiff.splitnewlines(basetext) + if a is None: + a = mdiff.splitnewlines(atext) + if b is None: + b = mdiff.splitnewlines(btext) + self.base = base + self.a = a + self.b = b + + def merge_lines(self, + name_a=None, + name_b=None, + name_base=None, + start_marker='<<<<<<<', + mid_marker='=======', + end_marker='>>>>>>>', + base_marker=None, + reprocess=False): + """Return merge in cvs-like form. + """ + self.conflicts = False + newline = '\n' + if len(self.a) > 0: + if self.a[0].endswith('\r\n'): + newline = '\r\n' + elif self.a[0].endswith('\r'): + newline = '\r' + if base_marker and reprocess: + raise CantReprocessAndShowBase() + if name_a: + start_marker = start_marker + ' ' + name_a + if name_b: + end_marker = end_marker + ' ' + name_b + if name_base and base_marker: + base_marker = base_marker + ' ' + name_base + merge_regions = self.merge_regions() + if reprocess is True: + merge_regions = self.reprocess_merge_regions(merge_regions) + for t in merge_regions: + what = t[0] + if what == 'unchanged': + for i in range(t[1], t[2]): + yield self.base[i] + elif what == 'a' or what == 'same': + for i in range(t[1], t[2]): + yield self.a[i] + elif what == 'b': + for i in range(t[1], t[2]): + yield self.b[i] + elif what == 'conflict': + self.conflicts = True + yield start_marker + newline + for i in range(t[3], t[4]): + yield self.a[i] + if base_marker is not None: + yield base_marker + newline + for i in range(t[1], t[2]): + yield self.base[i] + yield mid_marker + newline + for i in range(t[5], t[6]): + yield self.b[i] + yield end_marker + newline + else: + raise ValueError(what) + + def merge_annotated(self): + """Return merge with conflicts, showing origin of lines. + + Most useful for debugging merge. + """ + for t in self.merge_regions(): + what = t[0] + if what == 'unchanged': + for i in range(t[1], t[2]): + yield 'u | ' + self.base[i] + elif what == 'a' or what == 'same': + for i in range(t[1], t[2]): + yield what[0] + ' | ' + self.a[i] + elif what == 'b': + for i in range(t[1], t[2]): + yield 'b | ' + self.b[i] + elif what == 'conflict': + yield '<<<<\n' + for i in range(t[3], t[4]): + yield 'A | ' + self.a[i] + yield '----\n' + for i in range(t[5], t[6]): + yield 'B | ' + self.b[i] + yield '>>>>\n' + else: + raise ValueError(what) + + def merge_groups(self): + """Yield sequence of line groups. Each one is a tuple: + + 'unchanged', lines + Lines unchanged from base + + 'a', lines + Lines taken from a + + 'same', lines + Lines taken from a (and equal to b) + + 'b', lines + Lines taken from b + + 'conflict', base_lines, a_lines, b_lines + Lines from base were changed to either a or b and conflict. + """ + for t in self.merge_regions(): + what = t[0] + if what == 'unchanged': + yield what, self.base[t[1]:t[2]] + elif what == 'a' or what == 'same': + yield what, self.a[t[1]:t[2]] + elif what == 'b': + yield what, self.b[t[1]:t[2]] + elif what == 'conflict': + yield (what, + self.base[t[1]:t[2]], + self.a[t[3]:t[4]], + self.b[t[5]:t[6]]) + else: + raise ValueError(what) + + def merge_regions(self): + """Return sequences of matching and conflicting regions. + + This returns tuples, where the first value says what kind we + have: + + 'unchanged', start, end + Take a region of base[start:end] + + 'same', astart, aend + b and a are different from base but give the same result + + 'a', start, end + Non-clashing insertion from a[start:end] + + Method is as follows: + + The two sequences align only on regions which match the base + and both descendants. These are found by doing a two-way diff + of each one against the base, and then finding the + intersections between those regions. These "sync regions" + are by definition unchanged in both and easily dealt with. + + The regions in between can be in any of three cases: + conflicted, or changed on only one side. + """ + + # section a[0:ia] has been disposed of, etc + iz = ia = ib = 0 + + for zmatch, zend, amatch, aend, bmatch, bend in self.find_sync_regions(): + #print 'match base [%d:%d]' % (zmatch, zend) + + matchlen = zend - zmatch + assert matchlen >= 0 + assert matchlen == (aend - amatch) + assert matchlen == (bend - bmatch) + + len_a = amatch - ia + len_b = bmatch - ib + len_base = zmatch - iz + assert len_a >= 0 + assert len_b >= 0 + assert len_base >= 0 + + #print 'unmatched a=%d, b=%d' % (len_a, len_b) + + if len_a or len_b: + # try to avoid actually slicing the lists + equal_a = compare_range(self.a, ia, amatch, + self.base, iz, zmatch) + equal_b = compare_range(self.b, ib, bmatch, + self.base, iz, zmatch) + same = compare_range(self.a, ia, amatch, + self.b, ib, bmatch) + + if same: + yield 'same', ia, amatch + elif equal_a and not equal_b: + yield 'b', ib, bmatch + elif equal_b and not equal_a: + yield 'a', ia, amatch + elif not equal_a and not equal_b: + yield 'conflict', iz, zmatch, ia, amatch, ib, bmatch + else: + raise AssertionError("can't handle a=b=base but unmatched") + + ia = amatch + ib = bmatch + iz = zmatch + + # if the same part of the base was deleted on both sides + # that's OK, we can just skip it. + + + if matchlen > 0: + assert ia == amatch + assert ib == bmatch + assert iz == zmatch + + yield 'unchanged', zmatch, zend + iz = zend + ia = aend + ib = bend + + def reprocess_merge_regions(self, merge_regions): + """Where there are conflict regions, remove the agreed lines. + + Lines where both A and B have made the same changes are + eliminated. + """ + for region in merge_regions: + if region[0] != "conflict": + yield region + continue + type, iz, zmatch, ia, amatch, ib, bmatch = region + a_region = self.a[ia:amatch] + b_region = self.b[ib:bmatch] + matches = mdiff.get_matching_blocks(''.join(a_region), + ''.join(b_region)) + next_a = ia + next_b = ib + for region_ia, region_ib, region_len in matches[:-1]: + region_ia += ia + region_ib += ib + reg = self.mismatch_region(next_a, region_ia, next_b, + region_ib) + if reg is not None: + yield reg + yield 'same', region_ia, region_len + region_ia + next_a = region_ia + region_len + next_b = region_ib + region_len + reg = self.mismatch_region(next_a, amatch, next_b, bmatch) + if reg is not None: + yield reg + + def mismatch_region(next_a, region_ia, next_b, region_ib): + if next_a < region_ia or next_b < region_ib: + return 'conflict', None, None, next_a, region_ia, next_b, region_ib + mismatch_region = staticmethod(mismatch_region) + + def find_sync_regions(self): + """Return a list of sync regions, where both descendants match the base. + + Generates a list of (base1, base2, a1, a2, b1, b2). There is + always a zero-length sync region at the end of all the files. + """ + + ia = ib = 0 + amatches = mdiff.get_matching_blocks(self.basetext, self.atext) + bmatches = mdiff.get_matching_blocks(self.basetext, self.btext) + len_a = len(amatches) + len_b = len(bmatches) + + sl = [] + + while ia < len_a and ib < len_b: + abase, amatch, alen = amatches[ia] + bbase, bmatch, blen = bmatches[ib] + + # there is an unconflicted block at i; how long does it + # extend? until whichever one ends earlier. + i = intersect((abase, abase + alen), (bbase, bbase + blen)) + if i: + intbase = i[0] + intend = i[1] + intlen = intend - intbase + + # found a match of base[i[0], i[1]]; this may be less than + # the region that matches in either one + assert intlen <= alen + assert intlen <= blen + assert abase <= intbase + assert bbase <= intbase + + asub = amatch + (intbase - abase) + bsub = bmatch + (intbase - bbase) + aend = asub + intlen + bend = bsub + intlen + + assert self.base[intbase:intend] == self.a[asub:aend], \ + (self.base[intbase:intend], self.a[asub:aend]) + + assert self.base[intbase:intend] == self.b[bsub:bend] + + sl.append((intbase, intend, + asub, aend, + bsub, bend)) + + # advance whichever one ends first in the base text + if (abase + alen) < (bbase + blen): + ia += 1 + else: + ib += 1 + + intbase = len(self.base) + abase = len(self.a) + bbase = len(self.b) + sl.append((intbase, intbase, abase, abase, bbase, bbase)) + + return sl + + def find_unconflicted(self): + """Return a list of ranges in base that are not conflicted.""" + am = mdiff.get_matching_blocks(self.basetext, self.atext) + bm = mdiff.get_matching_blocks(self.basetext, self.btext) + + unc = [] + + while am and bm: + # there is an unconflicted block at i; how long does it + # extend? until whichever one ends earlier. + a1 = am[0][0] + a2 = a1 + am[0][2] + b1 = bm[0][0] + b2 = b1 + bm[0][2] + i = intersect((a1, a2), (b1, b2)) + if i: + unc.append(i) + + if a2 < b2: + del am[0] + else: + del bm[0] + + return unc + +def simplemerge(ui, local, base, other, **opts): + def readfile(filename): + f = open(filename, "rb") + text = f.read() + f.close() + if util.binary(text): + msg = _("%s looks like a binary file.") % filename + if not opts.get('quiet'): + ui.warn(_('warning: %s\n') % msg) + if not opts.get('text'): + raise util.Abort(msg) + return text + + name_a = local + name_b = other + labels = opts.get('label', []) + if labels: + name_a = labels.pop(0) + if labels: + name_b = labels.pop(0) + if labels: + raise util.Abort(_("can only specify two labels.")) + + try: + localtext = readfile(local) + basetext = readfile(base) + othertext = readfile(other) + except util.Abort: + return 1 + + local = os.path.realpath(local) + if not opts.get('print'): + opener = scmutil.opener(os.path.dirname(local)) + out = opener(os.path.basename(local), "w", atomictemp=True) + else: + out = sys.stdout + + reprocess = not opts.get('no_minimal') + + m3 = Merge3Text(basetext, localtext, othertext) + for line in m3.merge_lines(name_a=name_a, name_b=name_b, + reprocess=reprocess): + out.write(line) + + if not opts.get('print'): + out.close() + + if m3.conflicts: + if not opts.get('quiet'): + ui.warn(_("warning: conflicts during merge.\n")) + return 1 |