[PATCH 3 of 3 STABLE] clone: process 'lookup' return as an arbitrary symbol

[Yuya Nishihara]

On Thu, 26 Jul 2018 14:21:20 +0200, Boris Feld wrote:
> # HG changeset patch
> # User Boris Feld <boris.feld at octobus.net>
> # Date 1532595350 -7200
> #      Thu Jul 26 10:55:50 2018 +0200
> # Branch stable
> # Node ID 88a0bf46a3ffb78aaab203d13a7c9f53e244282b
> # Parent  a920f2620726ef26e6caed3d72b24297699b5b39
> # EXP-Topic compat-hggit
> # Available At https://bitbucket.org/octobus/mercurial-devel/
> #              hg pull https://bitbucket.org/octobus/mercurial-devel/ -r 88a0bf46a3ff
> 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.
> 
> diff --git a/mercurial/hg.py b/mercurial/hg.py
> --- a/mercurial/hg.py
> +++ b/mercurial/hg.py
> @@ -730,6 +730,19 @@ def clone(ui, peeropts, source, dest=Non
>  
>                  uprev = None
>                  status = None
> +                if checkout is not None and not node.isnode(checkout):

IIUC, hggit/hgsubversion may pass in a 20-length symbolic name?

> +                    # checkout was expected to be a node here because it was
> +                    # returned by peer.lookup.
> +                    #
> +                    # However, some extension (like hg-git) introduce peer not
> +                    # backed by a mercurial repository where lookup cannot
> +                    # return a node. Processing 'checkout' as an arbitrary
> +                    # symbols make it possible with these extensions keep
> +                    # working.
> +                    if scmutil.isrevsymbol(destrepo, checkout):
> +                        checkout = scmutil.revsymbol(destrepo, checkout).node()
> +                    else:
> +                        checkout = None

Do you have any plan to deprecate this hack?