hg: fix sending trees from the server to non-tree clients

Summary:
Previously we were trying to send trees to all clients during an
infinitepull, even ones that didn't support treemanifest. This caused
infinitepulls that required rebundling to fail for non-tree clients.

The fix is to just not send them unless the client is advertising the
capability.

Reviewed By: phillco

Differential Revision: D7432374

fbshipit-source-id: 1fae14a158ef56fe39439a718b1b98928f4e07b0

hgext/infinitepush/__init__.py

@@ -529,9 +529,21 @@ def _rebundle(bundlerepo, bundleroots, unknownhead, cgversion, bundlecaps):
     except KeyError:
         pass
     else:
+        # This parsing should be refactored to be shared with
+        # exchange.getbundlechunks. But I'll do that in a separate diff.
+        if bundlecaps is None:
+            bundlecaps = set()
+        b2caps = {}
+        for bcaps in bundlecaps:
+            if bcaps.startswith('bundle2='):
+                blob = util.urlreq.unquote(bcaps[len('bundle2='):])
+                b2caps.update(bundle2.decodecaps(blob))
+
         missing = outgoing.missing
         if remotefilelog.shallowbundle.cansendtrees(bundlerepo, missing,
-                                                    source='infinitepushpull'):
+                                                    source='infinitepushpull',
+                                                    bundlecaps=bundlecaps,
+                                                    b2caps=b2caps):
             treepart = treemod.createtreepackpart(bundlerepo, outgoing,
                             treemod.TREEGROUP_PARTTYPE2)
             parts.append(treepart)

hgext/remotefilelog/shallowbundle.py

@@ -509,7 +509,8 @@ def cansendtrees(repo, nodes, source=None, bundlecaps=None, b2caps=None):
     prefetch = AllTrees
 
     if repo.svfs.treemanifestserver:
-        if source == 'infinitepushpull':
+        if (source == 'infinitepushpull' and
+            'True' in b2caps.get('treemanifest', [])):
             result = AllTrees
         else:
             result = NoTrees

tests/test-fb-hgext-treemanifest-infinitepush.t

@@ -272,6 +272,18 @@ Pull a normal scratch branch into a treeonly client
   
   $ cd ..
 
+Pull a normal scratch branch into a normal client with rebundling where the
+server has treemanifest enabled.
+  $ cd normal-client
+  $ hg pull -r 42ec76eb772a --config extensions.treemanifest=! --config fastmanifest.usetree=False
+  pulling from ssh://user@dummy/master
+  no changes found
+  adding changesets
+  adding manifests
+  adding file changes
+  added 0 changesets with 1 changes to 1 files
+  $ cd ..
+
 Verify its not on the server
   $ cd master
   $ hg log -G