view contrib/dirstatenonnormalcheck.py @ 47682:78f7f0d490ee

dirstate-v2: Move fixed-size tree metadata into the docket file

Before this changeset, the dirstate-v2 data file contained not only nodes
and paths that may be reused when appending to an existing file,
but also some fixed-size metadata that applies to the entire tree
and was added at the end of the data file for every append.

This moves that metadata into the docket file, so that repeated "append"
operations without meaningful changes don’t actually need to grow any file.

Differential Revision: https://phab.mercurial-scm.org/D11098

# dirstatenonnormalcheck.py - extension to check the consistency of the
# dirstate's non-normal map
#
# For most operations on dirstate, this extensions checks that the nonnormalset
# contains the right entries.
# It compares the nonnormal file to a nonnormalset built from the map of all
# the files in the dirstate to check that they contain the same files.

from __future__ import absolute_import

from mercurial import (
    dirstate,
    extensions,
    pycompat,
)


def nonnormalentries(dmap):
    """Compute nonnormal entries from dirstate's dmap"""
    res = set()
    for f, e in dmap.iteritems():
        if e.state != b'n' or e.mtime == -1:
            res.add(f)
    return res


def checkconsistency(ui, orig, dmap, _nonnormalset, label):
    """Compute nonnormalset from dmap, check that it matches _nonnormalset"""
    nonnormalcomputedmap = nonnormalentries(dmap)
    if _nonnormalset != nonnormalcomputedmap:
        b_orig = pycompat.sysbytes(repr(orig))
        ui.develwarn(b"%s call to %s\n" % (label, b_orig), config=b'dirstate')
        ui.develwarn(b"inconsistency in nonnormalset\n", config=b'dirstate')
        b_nonnormal = pycompat.sysbytes(repr(_nonnormalset))
        ui.develwarn(b"[nonnormalset] %s\n" % b_nonnormal, config=b'dirstate')
        b_nonnormalcomputed = pycompat.sysbytes(repr(nonnormalcomputedmap))
        ui.develwarn(b"[map] %s\n" % b_nonnormalcomputed, config=b'dirstate')


def _checkdirstate(orig, self, *args, **kwargs):
    """Check nonnormal set consistency before and after the call to orig"""
    checkconsistency(
        self._ui, orig, self._map, self._map.nonnormalset, b"before"
    )
    r = orig(self, *args, **kwargs)
    checkconsistency(
        self._ui, orig, self._map, self._map.nonnormalset, b"after"
    )
    return r


def extsetup(ui):
    """Wrap functions modifying dirstate to check nonnormalset consistency"""
    dirstatecl = dirstate.dirstate
    devel = ui.configbool(b'devel', b'all-warnings')
    paranoid = ui.configbool(b'experimental', b'nonnormalparanoidcheck')
    if devel:
        extensions.wrapfunction(dirstatecl, '_writedirstate', _checkdirstate)
        if paranoid:
            # We don't do all these checks when paranoid is disable as it would
            # make the extension run very slowly on large repos
            extensions.wrapfunction(dirstatecl, 'normallookup', _checkdirstate)
            extensions.wrapfunction(dirstatecl, 'otherparent', _checkdirstate)
            extensions.wrapfunction(dirstatecl, 'normal', _checkdirstate)
            extensions.wrapfunction(dirstatecl, 'write', _checkdirstate)
            extensions.wrapfunction(dirstatecl, 'add', _checkdirstate)
            extensions.wrapfunction(dirstatecl, 'remove', _checkdirstate)
            extensions.wrapfunction(dirstatecl, 'merge', _checkdirstate)
            extensions.wrapfunction(dirstatecl, 'drop', _checkdirstate)