# HG changeset patch
# User Durham Goode <durham@fb.com>
# Date 1478132646 25200
# Node ID dc21ea3323c4113593137221b151627b83595a96
# Parent  1a0c1ad578331bfb4cc9cd6ee83bafe4b759f6f7
manifest: add manifestlog.get to obtain subdirectory instances

Previously manifestlog only allowed obtaining root level manifests. Future
patches will need direct access to subdirectory manifests as part of changegroup
creation, so let's add a get() function that knows how to deal with
subdirectories.

diff -r 1a0c1ad57833 -r dc21ea3323c4 mercurial/manifest.py
--- a/mercurial/manifest.py	Wed Nov 02 17:33:31 2016 -0700
+++ b/mercurial/manifest.py	Wed Nov 02 17:24:06 2016 -0700
@@ -1265,23 +1265,41 @@
         """Retrieves the manifest instance for the given node. Throws a
         LookupError if not found.
         """
-        if node in self._mancache:
-            cachemf = self._mancache[node]
-            # The old manifest may put non-ctx manifests in the cache, so skip
-            # those since they don't implement the full api.
-            if (isinstance(cachemf, manifestctx) or
-                isinstance(cachemf, treemanifestctx)):
-                return cachemf
+        return self.get('', node)
 
-        if node not in self._revlog.nodemap:
-            raise LookupError(node, self._revlog.indexfile,
-                              _('no node'))
-        if self._treeinmem:
-            m = treemanifestctx(self._repo, '', node)
+    def get(self, dir, node):
+        """Retrieves the manifest instance for the given node. Throws a
+        LookupError if not found.
+        """
+        if dir:
+            if self._revlog._treeondisk:
+                dirlog = self._revlog.dirlog(dir)
+                if node not in dirlog.nodemap:
+                    raise LookupError(node, dirlog.indexfile,
+                                      _('no node'))
+                m = treemanifestctx(self._repo, dir, node)
+            else:
+                raise error.Abort(
+                        _("cannot ask for manifest directory '%s' in a flat "
+                          "manifest") % dir)
         else:
-            m = manifestctx(self._repo, node)
-        if node != revlog.nullid:
-            self._mancache[node] = m
+            if node in self._mancache:
+                cachemf = self._mancache[node]
+                # The old manifest may put non-ctx manifests in the cache, so
+                # skip those since they don't implement the full api.
+                if (isinstance(cachemf, manifestctx) or
+                    isinstance(cachemf, treemanifestctx)):
+                    return cachemf
+
+            if node not in self._revlog.nodemap:
+                raise LookupError(node, self._revlog.indexfile,
+                                  _('no node'))
+            if self._treeinmem:
+                m = treemanifestctx(self._repo, '', node)
+            else:
+                m = manifestctx(self._repo, node)
+            if node != revlog.nullid:
+                self._mancache[node] = m
         return m
 
     def add(self, m, transaction, link, p1, p2, added, removed):