compat: add a compatibility layer for bookmark move The API was updated in 4.3 (712a85b3677f) we adapt to that.

compat: use 'safehasattr' over 'hasattr' 'hasattr' is broken in python 2.

stack: show short node of changesets in `hg stack -v` After this patch, hg stack -v shows short nodes for changesets which have topic index, i.e. excluding the bases except t0.

compat: use 'repo.cachevfs' when available In 4133c0b0fcd7 (core), the repository gained a new vfs dedicated to caches. We update the code to follow this new pattern.

debugobsconvert: take the lock when writing the obsstore file We were upgrading the store unprotected.

topics: add a test demonstarting sorting of topics by time using --age

branching: merge with stable

prev: allow to update to 't0' from 't1' When on the first changeset of a topic, one can move back one changeset to end up on t0. The new working copy parent to not belong to the topic, but the topic is still active. The next commit will create a new root to the active topic. You can get the same result using `hg up t0`

topic: add a 'topicidx()' to context This will be useful for the `t0` logic in `hg prev`

prev: retrieve the 'no-topic' result is a clear and reusable option We'll use it more, so let us make it pretty first.

prev: add '_getcurrenttopic' helper and use it We'll add more spot where this information is used.

prev: explicitly use 'p1' as a variable name This make the code clearer.