evolve: add a `--stop` flag for `hg evolve` command This patch adds a `--stop` flag for `hg evolve` command. The stop flag lets you stop the evolution from where you are and let you move to other things if you want. This fuctionality is great as user can decide to resolve conflicts later on, stop the command execution, do something else and get back once they has time or care about resolving them. As implementation details, it clears the evolvestate, updates to the parent of working directory clearing the uncommitted changes which also deletes the mergestate. A new test file test-evolve-stop.t is added with tests of the new flag added.

obsexchange: make compatible with some unreleased 4.5 versions We don't generally care to be compatible with unreleased versions of hg, but this is just a one-line change to be compatible with a range of commits before 158d4ecc03c8 (wireprotoserver: move all wire protocol handling logic out of hgweb, 2018-03-08), so hopefull it can be worth it.

compat: make override of createmarkers work on wrapped function If createmarkers() has been wrapped using functools.partial(), the __code__ attribute won't exist. Fix by unwrapping partial functions. I tried to find another attribute to use as proxy for the "__code__.co_argcount < 6", but there were no new functions or similar added in that commit.

previous/next: add -m short form for --merge This matches core's option to `hg update`. This patch also covers `hg next`, but test-check-commit.t only lets me mention one of them.

evolve: handle stabilization of merge changeset with both parents obsoleted This patch adds logic to stabilize an orphan merge changeset having both parents obsoleted. The logic tries to first stabilize the merge changeset on successor of second parent and then stabilize the new changeset formed on the successor of first parent. We are stabilizing on second parent first and then to second parent to preserve the first parent's successor as first parent of the merge changeset. Conflicts can occcur and we can loose processing information, therefore we store a variable in statefile `orphanmerge` which represents whether we are processing a merge changeset with both parents obsoleted. Thanks to Pierre-Yves David for suggesting this way and helping to understand the correctness of this. More rigourous test cases for this will be added in next patch.

state: add __setitem__() for cmdstate class Adding __setitem__() will help us in setting the value of variables stored in state files using `state[key] = value` in our code which is very convenient.

evolve: preserve the order of merge parents in `hg evolve --continue` This patch makes sure we preserves the order of merge parents in case of `hg evolve --continue`.

topics: include "operation" metadata in obsmarkers

grab: include "operation" metadata in obsmarkers

touch: include "operation" metadata in obsmarkers

split: include "operation" metadata in obsmarkers

prune: include "operation" metadata in obsmarkers

metaedit: include "operation" metadata in obsmarkers

fold: include "operation" metadata in obsmarkers

uncommit: include "operation" metadata in obsmarkers

evolve: include "operation" metadata in obsmarkers

amend: include "operation" metadata in obsmarkers This is for the legacy handling support for "hg commit --amend" case. I picked "amend" because it feels more natural than "commit". Besides, and more importantly, that's consistent what core uses.

compat: add wrapper for obsolete.createmarkers() that accepts "operation" arg I want to start passing the operation argument, but hg < 4.3 does not support it, so we need a compat wrapper. For older hg, the operation is simply ignored.

tests: do not glob out fixed dates Perhaps these dates historically have not been fixed, but they seem to be now. I got tired of not being able to use "run-tests.py -i".

evolve: de-duplicate some function calls _cleanup() was called in continueevolve() and evolve() function too. Let's call it at a single place for both the cases. Also call progresscb() outside of conditionals to call it both times.

evolve: move deletion of evolvestate out of continueevolve() function We need to extract some data at evolve() function from evolvestate.

evolve: load evolvestate before passing to continueevolve() This patch moves some code from continueevolve() to evolve() function so that we have a loaded evolvestate present in the evolve() function for post processing.

evolve: move the handling for non-continue part in else conditional This will help us do factor out which operations we want to do for continue, which for non-continue and which operations we want to do for both of them.

evolve: move the logic of continuation handling of `hg evolve` in own fn The function which defines the evolve command is pretty big with all the logic messed up there. It's better to have individual functions for individual uses. The movement of code will help in adding more logic to continue part in clean way. Moreover for implementing `hg continue`, we need all continuation handling in their own functions, so it will help there too.

CHANGELOG: add an entry about next and prev being interactive

prev: show changeset hash in --dry-run instead of rev numbers rev numbers can change, so it's better to show changeset hash.

prev: prompt user to choose parent in case of multiple parents This patch adds functionality to `hg prev` to prompt user to choose one parent to update when multiple parents exist. Surprisingly there were no tests for this case before this patch, I added one with this patch.

next: cleanup logic around return by returning early In the cmdnext function, there are some conditionals which returns early and some which sets a result value to be returned later. Let's return from all the conditionals early. There are if, elif and else involved, so it's sure we will end up in one of the conditional, each conditional will return, so it's guranteed that we are returning the correct value and returning everytime.