changeset 35011:a2dfc723b6b5

bundle: allow bundlerepo to support alternative manifest implementations

With our treemanifest logic, the manifests are no longer transported as part of
the changegroup and are no longer stored in a revlog. This means the
self.manifestlog line in bundlerepo.filestart no longer calls
_constructmanifest, and therefore does not consume the manifest portion of the
changegroup, which means filestart is not populated and we result in an infinite
loop.

The fix is to make filestart aware that self.manifestlog might not consume the
changegroup part, and consume it manually if necessary.

There's currently no way to test this in core, but our treemanifest extension
has tests to cover this.

Differential Revision: https://phab.mercurial-scm.org/D1329

--- a/mercurial/bundlerepo.py	Thu Oct 19 12:35:47 2017 +0200
+++ b/mercurial/bundlerepo.py	Tue Nov 07 10:16:53 2017 -0800
@@ -352,6 +352,15 @@
         self.filestart = self.bundle.tell()
         return m
 
+    def _consumemanifest(self):
+        """Consumes the manifest portion of the bundle, setting filestart so the
+        file portion can be read."""
+        self.bundle.seek(self.manstart)
+        self.bundle.manifestheader()
+        for delta in self.bundle.deltaiter():
+            pass
+        self.filestart = self.bundle.tell()
+
     @localrepo.unfilteredpropertycache
     def manstart(self):
         self.changelog
@@ -360,6 +369,14 @@
     @localrepo.unfilteredpropertycache
     def filestart(self):
         self.manifestlog
+
+        # If filestart was not set by self.manifestlog, that means the
+        # manifestlog implementation did not consume the manifests from the
+        # changegroup (ex: it might be consuming trees from a separate bundle2
+        # part instead). So we need to manually consume it.
+        if 'filestart' not in self.__dict__:
+            self._consumemanifest()
+
         return self.filestart
 
     def url(self):