view mercurial/filelog.py @ 9615:f51d1822d6fd

setup: refactor the version string to a subset of tag+tagdist-hash+date

Here is an array summarizing the mercurial version string:
      [A]       [B]   [C]           [D]
[1] clone      tag   clean  =>  tag
[2] clone      hash  clean  =>  latesttag+latesttagdistance-hash
[3] clone      tag   dirty  =>  tag+date
[4] clone      hash  dirty  =>  latesttag+latesttagdistance-hash+date
[5] archive    tag   clean  =>  tag
[6] archive    hash  clean  =>  latesttag+latesttagdistance-hash

Column [A]: Mercurial built from an hg *archive* or hg *clone* working directory
Column [B]: revision built has a *tag* or else default to the SHA1 *hash*
Column [C]: working tree *clean* or *dirty*
Column [D]: Mercurial version string

Over the previous version:
- row [5] did return just the node hash, now it returns the tag
- prepend the latest tag and the distance to it to rows [2][4][6]
- append also the date to row [3]; previously, it was just the tag
- the version string is with an empty string to avoid possible TypeError
  exceptions during string manipulations
- factorize the function to run hg commands; remove the error message as it is
  no more specific to the function.

This scheme enables to have first part of the version strings that can be
compared, whether it has been built from a tagged or untagged revision.
The second part of the version adds a hash for untagged revisions and today's
date if the working tree has local modifications.
As the version string does not contain spaces or special characters, it should
not break script parsing the 'hg version' command and should be usable for use
in file names.

The new code also ensure that the version string has exactly the same version
string, whether it has been built from an archive or from a clone.

# filelog.py - file history 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, incorporated herein by reference.

import revlog

class filelog(revlog.revlog):
    def __init__(self, opener, path):
        revlog.revlog.__init__(self, opener,
                        "/".join(("data", path + ".i")))

    def read(self, node):
        t = self.revision(node)
        if not t.startswith('\1\n'):
            return t
        s = t.index('\1\n', 2)
        return t[s+2:]

    def _readmeta(self, node):
        t = self.revision(node)
        if not t.startswith('\1\n'):
            return {}
        s = t.index('\1\n', 2)
        mt = t[2:s]
        m = {}
        for l in mt.splitlines():
            k, v = l.split(": ", 1)
            m[k] = v
        return m

    def add(self, text, meta, transaction, link, p1=None, p2=None):
        if meta or text.startswith('\1\n'):
            mt = ""
            if meta:
                mt = ["%s: %s\n" % (k, v) for k, v in meta.iteritems()]
            text = "\1\n%s\1\n%s" % ("".join(mt), text)
        return self.addrevision(text, transaction, link, p1, p2)

    def renamed(self, node):
        if self.parents(node)[0] != revlog.nullid:
            return False
        m = self._readmeta(node)
        if m and "copy" in m:
            return (m["copy"], revlog.bin(m["copyrev"]))
        return False

    def size(self, rev):
        """return the size of a given revision"""

        # for revisions with renames, we have to go the slow way
        node = self.node(rev)
        if self.renamed(node):
            return len(self.read(node))

        return revlog.revlog.size(self, rev)

    def cmp(self, node, text):
        """compare text with a given file revision"""

        # for renames, we have to go the slow way
        if self.renamed(node):
            t2 = self.read(node)
            return t2 != text

        return revlog.revlog.cmp(self, node, text)