view mercurial/manifest.py @ 18648:76b69cccb07a

export: show 'Date' header in a format that also is readable for humans

'export' is the official export format and used by patchbomb, but it would only
show date as a timestamp that most humans might find it hard to relate to. It
would be very convenient when reviewing a patch to be able to see what
timestamp the patch will end up with.

Mercurial has always used util.parsedate for parsing these headers. It can
handle 'all' date formats, so we could just as well use a readable one.

'export' will now use the format used by 'log' - which is the format described
as 'Unix date format' in the templating help. We assume that all parsers of '#
HG changeset patch'es can handle that.

# manifest.py - manifest revision class for mercurial
#
# Copyright 2005-2007 Matt Mackall <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from i18n import _
import mdiff, parsers, error, revlog, util
import array, struct

class manifestdict(dict):
    def __init__(self, mapping=None, flags=None):
        if mapping is None:
            mapping = {}
        if flags is None:
            flags = {}
        dict.__init__(self, mapping)
        self._flags = flags
    def flags(self, f):
        return self._flags.get(f, "")
    def withflags(self):
        return set(self._flags.keys())
    def set(self, f, flags):
        self._flags[f] = flags
    def copy(self):
        return manifestdict(self, dict.copy(self._flags))

class manifest(revlog.revlog):
    def __init__(self, opener):
        # we expect to deal with not more than three revs at a time in merge
        self._mancache = util.lrucachedict(3)
        revlog.revlog.__init__(self, opener, "00manifest.i")

    def parse(self, lines):
        mfdict = manifestdict()
        parsers.parse_manifest(mfdict, mfdict._flags, lines)
        return mfdict

    def readdelta(self, node):
        r = self.rev(node)
        return self.parse(mdiff.patchtext(self.revdiff(self.deltaparent(r), r)))

    def readfast(self, node):
        '''use the faster of readdelta or read'''
        r = self.rev(node)
        deltaparent = self.deltaparent(r)
        if deltaparent != revlog.nullrev and deltaparent in self.parentrevs(r):
            return self.readdelta(node)
        return self.read(node)

    def read(self, node):
        if node == revlog.nullid:
            return manifestdict() # don't upset local cache
        if node in self._mancache:
            return self._mancache[node][0]
        text = self.revision(node)
        arraytext = array.array('c', text)
        mapping = self.parse(text)
        self._mancache[node] = (mapping, arraytext)
        return mapping

    def _search(self, m, s, lo=0, hi=None):
        '''return a tuple (start, end) that says where to find s within m.

        If the string is found m[start:end] are the line containing
        that string.  If start == end the string was not found and
        they indicate the proper sorted insertion point.

        m should be a buffer or a string
        s is a string'''
        def advance(i, c):
            while i < lenm and m[i] != c:
                i += 1
            return i
        if not s:
            return (lo, lo)
        lenm = len(m)
        if not hi:
            hi = lenm
        while lo < hi:
            mid = (lo + hi) // 2
            start = mid
            while start > 0 and m[start - 1] != '\n':
                start -= 1
            end = advance(start, '\0')
            if m[start:end] < s:
                # we know that after the null there are 40 bytes of sha1
                # this translates to the bisect lo = mid + 1
                lo = advance(end + 40, '\n') + 1
            else:
                # this translates to the bisect hi = mid
                hi = start
        end = advance(lo, '\0')
        found = m[lo:end]
        if s == found:
            # we know that after the null there are 40 bytes of sha1
            end = advance(end + 40, '\n')
            return (lo, end + 1)
        else:
            return (lo, lo)

    def find(self, node, f):
        '''look up entry for a single file efficiently.
        return (node, flags) pair if found, (None, None) if not.'''
        if node in self._mancache:
            mapping = self._mancache[node][0]
            return mapping.get(f), mapping.flags(f)
        text = self.revision(node)
        start, end = self._search(text, f)
        if start == end:
            return None, None
        l = text[start:end]
        f, n = l.split('\0')
        return revlog.bin(n[:40]), n[40:-1]

    def add(self, map, transaction, link, p1=None, p2=None,
            changed=None):
        # apply the changes collected during the bisect loop to our addlist
        # return a delta suitable for addrevision
        def addlistdelta(addlist, x):
            # for large addlist arrays, building a new array is cheaper
            # than repeatedly modifying the existing one
            currentposition = 0
            newaddlist = array.array('c')

            for start, end, content in x:
                newaddlist += addlist[currentposition:start]
                if content:
                    newaddlist += array.array('c', content)

                currentposition = end

            newaddlist += addlist[currentposition:]

            deltatext = "".join(struct.pack(">lll", start, end, len(content))
                           + content for start, end, content in x)
            return deltatext, newaddlist

        def checkforbidden(l):
            for f in l:
                if '\n' in f or '\r' in f:
                    raise error.RevlogError(
                        _("'\\n' and '\\r' disallowed in filenames: %r") % f)

        # if we're using the cache, make sure it is valid and
        # parented by the same node we're diffing against
        if not (changed and p1 and (p1 in self._mancache)):
            files = sorted(map)
            checkforbidden(files)

            # if this is changed to support newlines in filenames,
            # be sure to check the templates/ dir again (especially *-raw.tmpl)
            hex, flags = revlog.hex, map.flags
            text = ''.join("%s\0%s%s\n" % (f, hex(map[f]), flags(f))
                           for f in files)
            arraytext = array.array('c', text)
            cachedelta = None
        else:
            added, removed = changed
            addlist = self._mancache[p1][1]

            checkforbidden(added)
            # combine the changed lists into one list for sorting
            work = [(x, False) for x in added]
            work.extend((x, True) for x in removed)
            # this could use heapq.merge() (from Python 2.6+) or equivalent
            # since the lists are already sorted
            work.sort()

            delta = []
            dstart = None
            dend = None
            dline = [""]
            start = 0
            # zero copy representation of addlist as a buffer
            addbuf = util.buffer(addlist)

            # start with a readonly loop that finds the offset of
            # each line and creates the deltas
            for f, todelete in work:
                # bs will either be the index of the item or the insert point
                start, end = self._search(addbuf, f, start)
                if not todelete:
                    l = "%s\0%s%s\n" % (f, revlog.hex(map[f]), map.flags(f))
                else:
                    if start == end:
                        # item we want to delete was not found, error out
                        raise AssertionError(
                                _("failed to remove %s from manifest") % f)
                    l = ""
                if dstart is not None and dstart <= start and dend >= start:
                    if dend < end:
                        dend = end
                    if l:
                        dline.append(l)
                else:
                    if dstart is not None:
                        delta.append([dstart, dend, "".join(dline)])
                    dstart = start
                    dend = end
                    dline = [l]

            if dstart is not None:
                delta.append([dstart, dend, "".join(dline)])
            # apply the delta to the addlist, and get a delta for addrevision
            deltatext, addlist = addlistdelta(addlist, delta)
            cachedelta = (self.rev(p1), deltatext)
            arraytext = addlist
            text = util.buffer(arraytext)

        n = self.addrevision(text, transaction, link, p1, p2, cachedelta)
        self._mancache[n] = (map, arraytext)

        return n