resurrect a changeset

[Christophe de Vienne]

Hi,

Yesterday I needed to remove the obsolescence marker of a changeset I
clumsily killed.
"hg touch" was not an option because the changeset was comming from a
central repository and I did not want to change it there.

The only way to do so is, at the moment, to remove .hg/store/obsstore
and re-pull, but then any local obsolete changeset is back. Although I
realize the actual need to un-kill a cset should not be a common
use-case, I still think a command to do so is needed.

Speaking with Pierre-Yves made it clear it is not a high priority task,
so I am willing to give it a try and write such a command.

So I come here for advice :
- Where should I start : patch evolve ? write my own extension ?
- Which APIs can I use to access the obsstore ?
- anything else I should know before starting ?


Thanks in advance

Christophe