compat: adapt to change in mercurial core The code around merge destination have been changed in core, we do some basic adaptation to make sure we don't crash. Further rework to adapt//take advantage of core change would probably be useful but this is not the point of this commit.

topic: handle merge.update function signature change I think this is backwards compatible with how it used to be called, but I didn't worry about it too much either.

Merge.

test-topic-dest: test fixes I should have put in the previous change I split a bigger change from marmoute that included some rebase support that I wanted to discuss more, but I didn't correctly commit my fixes to the tests before pushing. Oops.

topic: fix changing topics of commits that have an amend_source Includes a test for this specific case, but we should probably spend more time squinting at the interactions between the current topic wrapper function and commitctx for memctx instances.

topic: remove useless call to c.parents()

topic: fix up change logic a little and add debug logging

merge: use topic to pick default destination If the topic have multiple heads, reduce that. Otherwise, pick the branch we are on.

topic: introduce a 'ngtip' concept The concept is to be massively used in naming and default destination logic. The name is horrible so that people find a better one.

template: test that topic is accessible through template This comes free with the namespace feature but it is good to have.

test: adapt to newer mercurial

patch: import topic from patch header If the used Mercurial supports it, we import topic from patch headers.

patch: add topic to exported patch If used Mercurial supports it, we add a topic header to patches.

topic: work around stringmatcher moving during development of hg 3.6

topic: allow use of topic(.) to match the p1 topic As far as I can tell this matches the behavior of branch(.) in core hg in tht it matches p1's value rather than the wdir value.