--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hggit/overlay.py	Tue May 24 11:16:45 2011 -0700
@@ -0,0 +1,254 @@
+# overlay classes for repositories
+# unifies access to unimported git objects and committed hg objects
+# designed to support incoming
+#
+# incomplete, implemented on demand
+
+from mercurial import context
+from mercurial.node import bin, hex, nullid
+
+class overlaymanifest(object):
+    def __init__(self, repo, sha):
+        self.repo = repo
+        self.tree = repo.handler.git.get_object(sha)
+        self._map = None
+        self._flagmap = None
+
+    def copy(self):
+        return overlaymanifest(self.repo, self.tree.id)
+
+    def keys(self):
+        self.load()
+        return self._map.keys()
+
+    def flags(self, path):
+        self.load()
+
+        def hgflag(gitflag):
+            if gitflag & 0100:
+                return 'x'
+            elif gitflag & 020000:
+                return 'l'
+            else:
+                return ''
+
+        return hgflag(self._flagmap[path])
+
+    def load(self):
+        if self._map is not None:
+            return
+
+        self._map = {}
+        self._flagmap = {}
+
+        def addtree(tree, dirname):
+            for entry in tree.entries():
+                if entry[0] & 040000:
+                    # expand directory
+                    subtree = self.repo.handler.git.get_object(entry[2])
+                    addtree(subtree, dirname + entry[1] + '/')
+                else:
+                    path = dirname + entry[1]
+                    self._map[path] = bin(entry[2])
+                    self._flagmap[path] = entry[0]
+
+        addtree(self.tree, '')
+
+    def __iter__(self):
+        self.load()
+        return self._map.__iter__()
+
+    def __getitem__(self, path):
+        self.load()
+        return self._map[path]
+
+    def __delitem__(self, path):
+        del self._map[path]
+
+class overlayfilectx(object):
+    def __init__(self, repo, path, fileid=None):
+        self.repo = repo
+        self._path = path
+        self.fileid = fileid
+
+    # this is a hack to skip copy detection
+    def ancestors(self):
+        return [self, self]
+
+    def rev(self):
+        return -1
+
+    def path(self):
+        return self._path
+
+    def filelog(self):
+        return self.fileid
+
+    def data(self):
+        blob = self.repo.handler.git.get_object(self.fileid)
+        return blob.data
+
+class overlaychangectx(context.changectx):
+    def __init__(self, repo, sha):
+        self.repo = repo
+        self.commit = repo.handler.git.get_object(sha)
+
+    def node(self):
+        return bin(self.commit.id)
+
+    def rev(self):
+        return self.repo.rev(bin(self.commit.id))
+
+    def date(self):
+        return self.commit.author_time, self.commit.author_timezone
+
+    def branch(self):
+        return 'default'
+
+    def user(self):
+        return self.commit.author
+
+    def files(self):
+        return []
+
+    def extra(self):
+        return {}
+
+    def description(self):
+        return self.commit.message
+
+    def parents(self):
+        return [overlaychangectx(self.repo, sha) for sha in self.commit.parents]
+
+    def manifestnode(self):
+        return bin(self.commit.tree)
+
+    def hex(self):
+        return self.commit.id
+
+    def tags(self):
+        return []
+
+    def bookmarks(self):
+        return []
+
+    def manifest(self):
+        return overlaymanifest(self.repo, self.commit.tree)
+
+    def filectx(self, path, filelog=None):
+        mf = self.manifest()
+        return overlayfilectx(self.repo, path, mf[path])
+
+    def flags(self, path):
+        mf = self.manifest()
+        return mf.flags(path)
+
+    def __nonzero__(self):
+        return True
+
+class overlayrevlog(object):
+    def __init__(self, repo, base):
+        self.repo = repo
+        self.base = base
+
+    def parents(self, n):
+        gitrev = self.repo.revmap.get(n)
+        if not gitrev:
+            # we've reached a revision we have
+            return self.base.parents(n)
+        commit = self.repo.handler.git.get_object(n)
+
+        def gitorhg(n):
+            hn = self.repo.handler.map_hg_get(hex(n))
+            if hn is not None:
+                return bin(hn)
+            return n
+
+        # currently ignores the octopus
+        p1 = gitorhg(bin(commit.parents[0]))
+        if len(commit.parents) > 1:
+            p2 = gitorhg(bin(commit.parents[1]))
+        else:
+            p2 = nullid
+
+        return [p1, p2]
+
+    def parentrevs(self, rev):
+        return [self.rev(p) for p in self.parents(self.node(rev))]
+
+    def node(self, rev):
+        gitnode = self.repo.nodemap.get(rev)
+        if gitnode is None:
+            return self.base.node(rev)
+        return gitnode
+
+    def rev(self, n):
+        gitrev = self.repo.revmap.get(n)
+        if gitrev is None:
+             return self.base.rev(n)
+        return gitrev
+
+    def nodesbetween(self, nodelist, revs):
+        # this is called by pre-1.9 incoming with the nodelist we returned from
+        # getremotechanges. Just return it back.
+        return [nodelist]
+
+    def __len__(self):
+        return len(self.repo.handler.repo) + len(self.repo.revmap)
+
+
+class overlayrepo(object):
+    def __init__(self, handler, commits, refs):
+        self.handler = handler
+
+        self.changelog = overlayrevlog(self, handler.repo.changelog)
+        self.manifest = overlayrevlog(self, handler.repo.manifest)
+
+        # for incoming -p
+        self.root = handler.repo.root
+        self.getcwd = handler.repo.getcwd
+        self.status = handler.repo.status
+        self.ui = handler.repo.ui
+
+        self.revmap = None
+        self.nodemap = None
+        self.refmap = None
+        self.tagmap = None
+
+        self._makemaps(commits, refs)
+
+    def __getitem__(self, n):
+        if n not in self.revmap:
+            return self.handler.repo[n]
+        return overlaychangectx(self, n)
+
+    def nodebookmarks(self, n):
+        return self.refmap.get(n, [])
+
+    def nodetags(self, n):
+        return self.tagmap.get(n, [])
+
+    def rev(self, n):
+        return self.revmap[n]
+
+    def filectx(self, path, fileid=None):
+        return overlayfilectx(self, path, fileid=fileid)
+
+    def _makemaps(self, commits, refs):
+        baserev = self.handler.repo['tip'].rev()
+        self.revmap = {}
+        self.nodemap = {}
+        for i, n in enumerate(commits):
+            rev = baserev + i + 1
+            self.revmap[n] = rev
+            self.nodemap[rev] = n
+
+        self.refmap = {}
+        self.tagmap = {}
+        for ref in refs:
+            if ref.startswith('refs/heads/'):
+                refname = ref[11:]
+                self.refmap.setdefault(bin(refs[ref]), []).append(refname)
+            elif ref.startswith('refs/tags/'):
+                tagname = ref[10:]
+                self.tagmap.setdefault(bin(refs[ref]), []).append(tagname)