clone: process 'lookup' return as an arbitrary symbol...
clone: process 'lookup' return as an arbitrary symbol
In theory, checkout is expected to be a node here because it was returned by
peer.lookup.
In practice, multiple important extensions (like hg-git, hg-subversion) use
peers not backed by a mercurial repository where lookup cannot return a node.
Allowing arbitrary symbols is necessary to make these extensions working with
4.7.
We should probably introduce a new API in Core to have these extensions to
work without abusing the lookup API. In the meantime, a small change to
restore compatibility in 4.7 seems in order.