D2592: state: add registrar to register function to read old state files

[martinvonz (Martin von Zweigbergk)]

martinvonz added inline comments.

INLINE COMMENTS

> state.py:104
> +        should return a dict of data stored in state file."""
> +        assert path not in oldstatefilefns
> +        oldstatefilefns[path] = func

I think we're used ProgrammingError elsewhere for this kind of thing

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D2592

To: pulkit, #hg-reviewers
Cc: martinvonz, mercurial-devel