evolvecmd: introduce fn to be wrapped by extensions resolving content-div The function added will be used by extension by wrapping it and adding logic to merge data introduced by them. For example: topic extension can wrap this function and add logic to merge topic names.

evolvecmd: move remaining logic to merge commit desc to existing utility fn This was a bit awful because we had a utility function and still we did some of merging outside of that fn. So let's move the remaining parts there.

amend: allow aborting an `amend --patch` by saving an empty file (issue5925) This patch fixes issue5925 by allow aborting a `hg amend --patch` call by saving an empty patch file. This is similar to aborting of `hg amend` when commit message is empty. Test changes demonstrate the fix.

tests: add a test to demonstrate issue5925 The issue will be fixed in next patch.

test: fix possible output change from 4.7 Change in debug timing can display these extra messages.

state: add the get() method that evolvecmd:1836 expects

rewing: prevent rewind in case of uncommitted changes rewind can update, which means merge and troubles. We might relax this limitation in the future.

rewind: default to rewinding the current stack

rewing: add the ability to rewind "from" revisions

evolve: exclude "identical" precursors from the precursors set I'm not sure it is the right thing to do, but it simply thing a lot for now. Otherwise, using 'precursors' to find rewind direction become too complex. This is going to give problematic result in case of prune. Since there are no other precursors to follow.

rewind: move revision selection into its own function This will help making the logic more advanced.

rewind: automatically rewind entire stack We now rewind the full stack, avoiding creating orphans. A `--exact` flag is added to force rewinding only the explicitly specified changesets.

rewind: add a test about rewinding top of stack For now this rewind is creating an orphan. We add the test to check the behavior in that case.

rewind: use rewinded parent when creating multiple changesets Use use the rewinded parent instead of creating orphans based on identical, but obsolete, changesets.

rewind: add a test for rewinding a fold The code already have basic support for case. However the result create orphan that will need to be improved. However, we keep this changeset simple.

rewind: add a test for rewinding a split There are no code change needed but it is worth testing on its own.

rewind: update the working copy if it gets obsoleted If the working copy parent is rewinded, follow the rewind.

rewind: add a message about obsolete changeset Not the best output, but useful to have the data. We can improve that later.

rewind: obsolete latest successors unless instructed otherwise To prevent the creations of divergence, we automatically mark the successors set of the rewinded changeset as obsoleted by the rewind result. A new flag `--as-divergence` is added to disable this behavior.

rewind: test rewinding an amended changesets We are now able to rewind a simple amended changeset. For now, its current successors has not been obsoleted and we created divergence.

rewind: add a message about the rewinded changesets This helps to understand what happened.

rewind: add a proto version of the command This first version focus on rewinding a single revision without care for the consequence.

stablesort: make sure heads are processed in sorted order changeset 72621094505f will fix some ordering issue in the `heads` revset so we stabilise the output in advance.

evolve: move the bookmarks also when updating to successor (issue5923) When we are on an obsolete node and does `hg evolve`, it updates to it's sucessor, however it does not move the bookmark to the successor. This patch adds logic to make sure we move the bookmark too. Test change demonstrates the fix.

tests: add test to demonstrate issue5923 This will be fixed in upcoming patch.

changelog: add an entry about the new `evolve.interrupted` section

evolve: make one missed error to align other error messages Previous patches missed this error to change it to the new format. Let's align this with all other messages raised by `hg evolve` command.

evolve: raise error.InterventionRequired instead of Abort when conflicts error.InterventionRequired is a better error to raise in such cases. Thanks to marmoute for noticing this.

changelog: add a changelog entry about divergence resolution We made a lots of progress there.

evolve: create resolved cset on successors of current parents While resolving content-divergence, sometimes, the parent can be obsolete and have a successor. We should consider the successors of the parents instead of obsolete parents as that will do something like orphan+content-divergence resolution both at the same time which is powerful and results in a single stack while resolving content-divergence of stacks. The test changes demonstrates that we can now successfully evolve a content divergent stack.