--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hgext/lfs/wrapper.py	Tue Nov 14 00:06:23 2017 -0500
@@ -0,0 +1,247 @@
+# wrapper.py - methods wrapping core mercurial logic
+#
+# Copyright 2017 Facebook, Inc.
+#
+# This software may be used and distributed according to the terms of the
+# GNU General Public License version 2 or any later version.
+
+from __future__ import absolute_import
+
+import hashlib
+
+from mercurial import (
+    error,
+    filelog,
+    revlog,
+    util,
+)
+from mercurial.i18n import _
+from mercurial.node import bin, nullid, short
+
+from . import (
+    blobstore,
+    pointer,
+)
+
+def supportedoutgoingversions(orig, repo):
+    versions = orig(repo)
+    versions.discard('01')
+    versions.discard('02')
+    versions.add('03')
+    return versions
+
+def allsupportedversions(orig, ui):
+    versions = orig(ui)
+    versions.add('03')
+    return versions
+
+def bypasscheckhash(self, text):
+    return False
+
+def readfromstore(self, text):
+    """Read filelog content from local blobstore transform for flagprocessor.
+
+    Default tranform for flagprocessor, returning contents from blobstore.
+    Returns a 2-typle (text, validatehash) where validatehash is True as the
+    contents of the blobstore should be checked using checkhash.
+    """
+    p = pointer.deserialize(text)
+    oid = p.oid()
+    store = self.opener.lfslocalblobstore
+    if not store.has(oid):
+        p.filename = getattr(self, 'indexfile', None)
+        self.opener.lfsremoteblobstore.readbatch([p], store)
+    text = store.read(oid)
+
+    # pack hg filelog metadata
+    hgmeta = {}
+    for k in p.keys():
+        if k.startswith('x-hg-'):
+            name = k[len('x-hg-'):]
+            hgmeta[name] = p[k]
+    if hgmeta or text.startswith('\1\n'):
+        text = filelog.packmeta(hgmeta, text)
+
+    return (text, True)
+
+def writetostore(self, text):
+    # hg filelog metadata (includes rename, etc)
+    hgmeta, offset = filelog.parsemeta(text)
+    if offset and offset > 0:
+        # lfs blob does not contain hg filelog metadata
+        text = text[offset:]
+
+    # git-lfs only supports sha256
+    oid = hashlib.sha256(text).hexdigest()
+    self.opener.lfslocalblobstore.write(oid, text)
+
+    # replace contents with metadata
+    longoid = 'sha256:%s' % oid
+    metadata = pointer.gitlfspointer(oid=longoid, size=str(len(text)))
+
+    # by default, we expect the content to be binary. however, LFS could also
+    # be used for non-binary content. add a special entry for non-binary data.
+    # this will be used by filectx.isbinary().
+    if not util.binary(text):
+        # not hg filelog metadata (affecting commit hash), no "x-hg-" prefix
+        metadata['x-is-binary'] = '0'
+
+    # translate hg filelog metadata to lfs metadata with "x-hg-" prefix
+    if hgmeta is not None:
+        for k, v in hgmeta.iteritems():
+            metadata['x-hg-%s' % k] = v
+
+    rawtext = metadata.serialize()
+    return (rawtext, False)
+
+def _islfs(rlog, node=None, rev=None):
+    if rev is None:
+        if node is None:
+            # both None - likely working copy content where node is not ready
+            return False
+        rev = rlog.rev(node)
+    else:
+        node = rlog.node(rev)
+    if node == nullid:
+        return False
+    flags = rlog.flags(rev)
+    return bool(flags & revlog.REVIDX_EXTSTORED)
+
+def filelogaddrevision(orig, self, text, transaction, link, p1, p2,
+                       cachedelta=None, node=None,
+                       flags=revlog.REVIDX_DEFAULT_FLAGS, **kwds):
+    threshold = self.opener.options['lfsthreshold']
+    textlen = len(text)
+    # exclude hg rename meta from file size
+    meta, offset = filelog.parsemeta(text)
+    if offset:
+        textlen -= offset
+
+    if threshold and textlen > threshold:
+        flags |= revlog.REVIDX_EXTSTORED
+
+    return orig(self, text, transaction, link, p1, p2, cachedelta=cachedelta,
+                node=node, flags=flags, **kwds)
+
+def filelogrenamed(orig, self, node):
+    if _islfs(self, node):
+        rawtext = self.revision(node, raw=True)
+        if not rawtext:
+            return False
+        metadata = pointer.deserialize(rawtext)
+        if 'x-hg-copy' in metadata and 'x-hg-copyrev' in metadata:
+            return metadata['x-hg-copy'], bin(metadata['x-hg-copyrev'])
+        else:
+            return False
+    return orig(self, node)
+
+def filelogsize(orig, self, rev):
+    if _islfs(self, rev=rev):
+        # fast path: use lfs metadata to answer size
+        rawtext = self.revision(rev, raw=True)
+        metadata = pointer.deserialize(rawtext)
+        return int(metadata['size'])
+    return orig(self, rev)
+
+def filectxcmp(orig, self, fctx):
+    """returns True if text is different than fctx"""
+    # some fctx (ex. hg-git) is not based on basefilectx and do not have islfs
+    if self.islfs() and getattr(fctx, 'islfs', lambda: False)():
+        # fast path: check LFS oid
+        p1 = pointer.deserialize(self.rawdata())
+        p2 = pointer.deserialize(fctx.rawdata())
+        return p1.oid() != p2.oid()
+    return orig(self, fctx)
+
+def filectxisbinary(orig, self):
+    if self.islfs():
+        # fast path: use lfs metadata to answer isbinary
+        metadata = pointer.deserialize(self.rawdata())
+        # if lfs metadata says nothing, assume it's binary by default
+        return bool(int(metadata.get('x-is-binary', 1)))
+    return orig(self)
+
+def filectxislfs(self):
+    return _islfs(self.filelog(), self.filenode())
+
+def vfsinit(orig, self, othervfs):
+    orig(self, othervfs)
+    # copy lfs related options
+    for k, v in othervfs.options.items():
+        if k.startswith('lfs'):
+            self.options[k] = v
+    # also copy lfs blobstores. note: this can run before reposetup, so lfs
+    # blobstore attributes are not always ready at this time.
+    for name in ['lfslocalblobstore', 'lfsremoteblobstore']:
+        if util.safehasattr(othervfs, name):
+            setattr(self, name, getattr(othervfs, name))
+
+def _canskipupload(repo):
+    # if remotestore is a null store, upload is a no-op and can be skipped
+    return isinstance(repo.svfs.lfsremoteblobstore, blobstore._nullremote)
+
+def candownload(repo):
+    # if remotestore is a null store, downloads will lead to nothing
+    return not isinstance(repo.svfs.lfsremoteblobstore, blobstore._nullremote)
+
+def uploadblobsfromrevs(repo, revs):
+    '''upload lfs blobs introduced by revs
+
+    Note: also used by other extensions e. g. infinitepush. avoid renaming.
+    '''
+    if _canskipupload(repo):
+        return
+    pointers = extractpointers(repo, revs)
+    uploadblobs(repo, pointers)
+
+def prepush(pushop):
+    """Prepush hook.
+
+    Read through the revisions to push, looking for filelog entries that can be
+    deserialized into metadata so that we can block the push on their upload to
+    the remote blobstore.
+    """
+    return uploadblobsfromrevs(pushop.repo, pushop.outgoing.missing)
+
+def writenewbundle(orig, ui, repo, source, filename, bundletype, outgoing,
+                   *args, **kwargs):
+    """upload LFS blobs added by outgoing revisions on 'hg bundle'"""
+    uploadblobsfromrevs(repo, outgoing.missing)
+    return orig(ui, repo, source, filename, bundletype, outgoing, *args,
+                **kwargs)
+
+def extractpointers(repo, revs):
+    """return a list of lfs pointers added by given revs"""
+    ui = repo.ui
+    if ui.debugflag:
+        ui.write(_('lfs: computing set of blobs to upload\n'))
+    pointers = {}
+    for r in revs:
+        ctx = repo[r]
+        for p in pointersfromctx(ctx).values():
+            pointers[p.oid()] = p
+    return pointers.values()
+
+def pointersfromctx(ctx):
+    """return a dict {path: pointer} for given single changectx"""
+    result = {}
+    for f in ctx.files():
+        if f not in ctx:
+            continue
+        fctx = ctx[f]
+        if not _islfs(fctx.filelog(), fctx.filenode()):
+            continue
+        try:
+            result[f] = pointer.deserialize(fctx.rawdata())
+        except pointer.InvalidPointer as ex:
+            raise error.Abort(_('lfs: corrupted pointer (%s@%s): %s\n')
+                              % (f, short(ctx.node()), ex))
+    return result
+
+def uploadblobs(repo, pointers):
+    """upload given pointers from local blobstore"""
+    if not pointers:
+        return
+
+    remoteblob = repo.svfs.lfsremoteblobstore
+    remoteblob.writebatch(pointers, repo.svfs.lfslocalblobstore)