relnotes/next

copies-rust: extract conflicting value comparison in its own function

First, that logic is complicated enough to be in it own function. Second, we
want to start adding alternative path within the merge code so we need this logic
easily accessible in multiple places.

Differential Revision: https://phab.mercurial-scm.org/D9424

== New Features ==

 * There is a new config section for templates used by hg commands. It
   is called `[command-templates]`. Some existing config options have
   been deprecated in favor of config options in the new
   section. These are: `ui.logtemplate` to `command-templates.log`,
   `ui.graphnodetemplate` to `command-templates.graphnode`,
   `ui.mergemarkertemplate` to `command-templates.mergemarker`,
   `ui.pre-merge-tool-output-template` to
   `command-templates.pre-merge-tool-output`.

 * There is a new set of config options for the template used for the
   one-line commit summary displayed by various commands, such as `hg
   rebase`. The main one is `command-templates.oneline-summary`. That
   can be overridden per command with
   `command-templates.oneline-summary.<command>`, where `<command>`
   can be e.g. `rebase`. As part of this effort, the default format
   from `hg rebase` was reorganized a bit.

 * `hg strip`, from the strip extension, is now a core command, `hg
   debugstrip`. The extension remains for compatibility.

 * `hg diff` now supports `--from <rev>` and `--to <rev>` arguments as
   clearer alternatives to `-r <revs>`. `-r <revs>` has been
   deprecated.

 * The memory footprint per changeset during pull/unbundle
   operations has been further reduced.

 * There is a new internal merge tool called `internal:mergediff` (can
   be set as the value for the `merge` config in the `[ui]`
   section). It resolves merges the same was as `internal:merge` and
   `internal:merge3`, but it shows conflicts differently. Instead of
   showing 2 or 3 snapshots of the conflicting pieces of code, it
   shows one snapshot and a diff. This may be useful when at least one
   side of the conflict is similar to the base.

== New Experimental Features ==

* `experimental.single-head-per-branch:public-changes-only` can be used
  restrict the single head check to public revision. This is useful for
  overlay repository that have both a publishing and non-publishing view
  of the same storage.


== Bug Fixes ==



== Backwards Compatibility Changes ==



== Internal API Changes ==