view mercurial/templatekw.py @ 16696:d1afbf03e69a

rebase: allow collapsing branches in place (issue3111)

We allow rebase plus collapse, but not collapse only? I imagine people would
rebase first then collapse once they are sure the rebase is correct and it is
the right time to finish it.

I was reluctant to submit this patch for reasons detailed below, but it
improves rebase --collapse usefulness so much it is worth the ugliness.

The fix is ugly because we should be fixing the collapse code path rather than
the merge. Collapsing by merging changesets repeatedly is inefficient compared
to what commit --amend does: commitctx(), update, strip. The problem with the
latter is, to generate the synthetic changeset, copy records are gathered with
copies.pathcopies(). copies.pathcopies() is still implemented with merging in
mind and discards information like file replaced by the copy of another,
criss-cross copies and so forth. I believe this information should not be lost,
even if we decide not to interpret it fully later, at merge time.

The second issue with improving rebase --collapse is the option should not be
there to begin with. Rebasing and collapsing are orthogonal and a dedicated
command would probably enable a better, simpler ui. We should avoid advertizing
rebase --collapse, but with this fix it becomes the best shipped solution to
collapse changesets.

And for the record, available techniques are:
- revert + commit + strip: lose copies
- mq/qfold: repeated patching() (mostly correct, fragile)
- rebase: repeated merges (mostly correct, fragile)
- collapse: revert + tag rewriting wizardry, lose copies
- histedit: repeated patching() (mostly correct, fragile)
- amend: copies.pathcopies() + commitctx() + update + strip

# templatekw.py - common changeset template keywords
#
# Copyright 2005-2009 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 node import hex
import patch, util, error
import hbisect

def showlist(name, values, plural=None, **args):
    '''expand set of values.
    name is name of key in template map.
    values is list of strings or dicts.
    plural is plural of name, if not simply name + 's'.

    expansion works like this, given name 'foo'.

    if values is empty, expand 'no_foos'.

    if 'foo' not in template map, return values as a string,
    joined by space.

    expand 'start_foos'.

    for each value, expand 'foo'. if 'last_foo' in template
    map, expand it instead of 'foo' for last key.

    expand 'end_foos'.
    '''
    templ = args['templ']
    if plural:
        names = plural
    else: names = name + 's'
    if not values:
        noname = 'no_' + names
        if noname in templ:
            yield templ(noname, **args)
        return
    if name not in templ:
        if isinstance(values[0], str):
            yield ' '.join(values)
        else:
            for v in values:
                yield dict(v, **args)
        return
    startname = 'start_' + names
    if startname in templ:
        yield templ(startname, **args)
    vargs = args.copy()
    def one(v, tag=name):
        try:
            vargs.update(v)
        except (AttributeError, ValueError):
            try:
                for a, b in v:
                    vargs[a] = b
            except ValueError:
                vargs[name] = v
        return templ(tag, **vargs)
    lastname = 'last_' + name
    if lastname in templ:
        last = values.pop()
    else:
        last = None
    for v in values:
        yield one(v)
    if last is not None:
        yield one(last, tag=lastname)
    endname = 'end_' + names
    if endname in templ:
        yield templ(endname, **args)

def getfiles(repo, ctx, revcache):
    if 'files' not in revcache:
        revcache['files'] = repo.status(ctx.p1().node(), ctx.node())[:3]
    return revcache['files']

def getlatesttags(repo, ctx, cache):
    '''return date, distance and name for the latest tag of rev'''

    if 'latesttags' not in cache:
        # Cache mapping from rev to a tuple with tag date, tag
        # distance and tag name
        cache['latesttags'] = {-1: (0, 0, 'null')}
    latesttags = cache['latesttags']

    rev = ctx.rev()
    todo = [rev]
    while todo:
        rev = todo.pop()
        if rev in latesttags:
            continue
        ctx = repo[rev]
        tags = [t for t in ctx.tags() if repo.tagtype(t) == 'global']
        if tags:
            latesttags[rev] = ctx.date()[0], 0, ':'.join(sorted(tags))
            continue
        try:
            # The tuples are laid out so the right one can be found by
            # comparison.
            pdate, pdist, ptag = max(
                latesttags[p.rev()] for p in ctx.parents())
        except KeyError:
            # Cache miss - recurse
            todo.append(rev)
            todo.extend(p.rev() for p in ctx.parents())
            continue
        latesttags[rev] = pdate, pdist + 1, ptag
    return latesttags[rev]

def getrenamedfn(repo, endrev=None):
    rcache = {}
    if endrev is None:
        endrev = len(repo)

    def getrenamed(fn, rev):
        '''looks up all renames for a file (up to endrev) the first
        time the file is given. It indexes on the changerev and only
        parses the manifest if linkrev != changerev.
        Returns rename info for fn at changerev rev.'''
        if fn not in rcache:
            rcache[fn] = {}
            fl = repo.file(fn)
            for i in fl:
                lr = fl.linkrev(i)
                renamed = fl.renamed(fl.node(i))
                rcache[fn][lr] = renamed
                if lr >= endrev:
                    break
        if rev in rcache[fn]:
            return rcache[fn][rev]

        # If linkrev != rev (i.e. rev not found in rcache) fallback to
        # filectx logic.
        try:
            return repo[rev][fn].renamed()
        except error.LookupError:
            return None

    return getrenamed


def showauthor(repo, ctx, templ, **args):
    """:author: String. The unmodified author of the changeset."""
    return ctx.user()

def showbisect(repo, ctx, templ, **args):
    """:bisect: String. The changeset bisection status."""
    return hbisect.label(repo, ctx.node())

def showbranch(**args):
    """:branch: String. The name of the branch on which the changeset was
    committed.
    """
    return args['ctx'].branch()

def showbranches(**args):
    """:branches: List of strings. The name of the branch on which the
    changeset was committed. Will be empty if the branch name was
    default.
    """
    branch = args['ctx'].branch()
    if branch != 'default':
        return showlist('branch', [branch], plural='branches', **args)

def showbookmarks(**args):
    """:bookmarks: List of strings. Any bookmarks associated with the
    changeset.
    """
    bookmarks = args['ctx'].bookmarks()
    return showlist('bookmark', bookmarks, **args)

def showchildren(**args):
    """:children: List of strings. The children of the changeset."""
    ctx = args['ctx']
    childrevs = ['%d:%s' % (cctx, cctx) for cctx in ctx.children()]
    return showlist('children', childrevs, **args)

def showdate(repo, ctx, templ, **args):
    """:date: Date information. The date when the changeset was committed."""
    return ctx.date()

def showdescription(repo, ctx, templ, **args):
    """:desc: String. The text of the changeset description."""
    return ctx.description().strip()

def showdiffstat(repo, ctx, templ, **args):
    """:diffstat: String. Statistics of changes with the following format:
    "modified files: +added/-removed lines"
    """
    stats = patch.diffstatdata(util.iterlines(ctx.diff()))
    maxname, maxtotal, adds, removes, binary = patch.diffstatsum(stats)
    return '%s: +%s/-%s' % (len(stats), adds, removes)

def showextras(**args):
    templ = args['templ']
    for key, value in sorted(args['ctx'].extra().items()):
        args = args.copy()
        args.update(dict(key=key, value=value))
        yield templ('extra', **args)

def showfileadds(**args):
    """:file_adds: List of strings. Files added by this changeset."""
    repo, ctx, revcache = args['repo'], args['ctx'], args['revcache']
    return showlist('file_add', getfiles(repo, ctx, revcache)[1], **args)

def showfilecopies(**args):
    """:file_copies: List of strings. Files copied in this changeset with
    their sources.
    """
    cache, ctx = args['cache'], args['ctx']
    copies = args['revcache'].get('copies')
    if copies is None:
        if 'getrenamed' not in cache:
            cache['getrenamed'] = getrenamedfn(args['repo'])
        copies = []
        getrenamed = cache['getrenamed']
        for fn in ctx.files():
            rename = getrenamed(fn, ctx.rev())
            if rename:
                copies.append((fn, rename[0]))

    c = [{'name': x[0], 'source': x[1]} for x in copies]
    return showlist('file_copy', c, plural='file_copies', **args)

# showfilecopiesswitch() displays file copies only if copy records are
# provided before calling the templater, usually with a --copies
# command line switch.
def showfilecopiesswitch(**args):
    """:file_copies_switch: List of strings. Like "file_copies" but displayed
    only if the --copied switch is set.
    """
    copies = args['revcache'].get('copies') or []
    c = [{'name': x[0], 'source': x[1]} for x in copies]
    return showlist('file_copy', c, plural='file_copies', **args)

def showfiledels(**args):
    """:file_dels: List of strings. Files removed by this changeset."""
    repo, ctx, revcache = args['repo'], args['ctx'], args['revcache']
    return showlist('file_del', getfiles(repo, ctx, revcache)[2], **args)

def showfilemods(**args):
    """:file_mods: List of strings. Files modified by this changeset."""
    repo, ctx, revcache = args['repo'], args['ctx'], args['revcache']
    return showlist('file_mod', getfiles(repo, ctx, revcache)[0], **args)

def showfiles(**args):
    """:files: List of strings. All files modified, added, or removed by this
    changeset.
    """
    return showlist('file', args['ctx'].files(), **args)

def showlatesttag(repo, ctx, templ, cache, **args):
    """:latesttag: String. Most recent global tag in the ancestors of this
    changeset.
    """
    return getlatesttags(repo, ctx, cache)[2]

def showlatesttagdistance(repo, ctx, templ, cache, **args):
    """:latesttagdistance: Integer. Longest path to the latest tag."""
    return getlatesttags(repo, ctx, cache)[1]

def showmanifest(**args):
    repo, ctx, templ = args['repo'], args['ctx'], args['templ']
    args = args.copy()
    args.update(dict(rev=repo.manifest.rev(ctx.changeset()[0]),
                     node=hex(ctx.changeset()[0])))
    return templ('manifest', **args)

def shownode(repo, ctx, templ, **args):
    """:node: String. The changeset identification hash, as a 40 hexadecimal
    digit string.
    """
    return ctx.hex()

def showphase(repo, ctx, templ, **args):
    """:phase: String. The changeset phase name."""
    return ctx.phasestr()

def showphaseidx(repo, ctx, templ, **args):
    """:phaseidx: Integer. The changeset phase index."""
    return ctx.phase()

def showrev(repo, ctx, templ, **args):
    """:rev: Integer. The repository-local changeset revision number."""
    return ctx.rev()

def showtags(**args):
    """:tags: List of strings. Any tags associated with the changeset."""
    return showlist('tag', args['ctx'].tags(), **args)

# keywords are callables like:
# fn(repo, ctx, templ, cache, revcache, **args)
# with:
# repo - current repository instance
# ctx - the changectx being displayed
# templ - the templater instance
# cache - a cache dictionary for the whole templater run
# revcache - a cache dictionary for the current revision
keywords = {
    'author': showauthor,
    'bisect': showbisect,
    'branch': showbranch,
    'branches': showbranches,
    'bookmarks': showbookmarks,
    'children': showchildren,
    'date': showdate,
    'desc': showdescription,
    'diffstat': showdiffstat,
    'extras': showextras,
    'file_adds': showfileadds,
    'file_copies': showfilecopies,
    'file_copies_switch': showfilecopiesswitch,
    'file_dels': showfiledels,
    'file_mods': showfilemods,
    'files': showfiles,
    'latesttag': showlatesttag,
    'latesttagdistance': showlatesttagdistance,
    'manifest': showmanifest,
    'node': shownode,
    'phase': showphase,
    'phaseidx': showphaseidx,
    'rev': showrev,
    'tags': showtags,
}

# tell hggettext to extract docstrings from these functions:
i18nfunctions = keywords.values()