relnotes/next
author Joerg Sonnenberger <joerg@bec.de>
Fri, 18 Dec 2020 14:45:28 +0100
changeset 46254 c4b792fa109e
parent 46237 bc884e31b8c8
child 46368 bb3a5c0df06b
child 46451 38d76908c011
permissions -rw-r--r--
branchmap: avoid ancestor computations in absence of non-continous branches The branchhead computation is one of the more heavy operations for bigger repositories as it has to scan all changesets and potentially involves the expensive computation of the ancestor sets. Redo the computation to handle the common cases directly and use tighter conditions for when the ancestor scan is necessary. Most importantly, avoid it completely if the non-continous branches are processed in one update as seen in the initial computation after a clone. For the Mercurial repository, it gives a small 2-3% performance boost. For the NetBSD test repository, it cuts the time in half. Differential Revision: https://phab.mercurial-scm.org/D9631

== 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` and `hg extdiff` now support `--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. The new marker style
   is also supported by "premerge" as
   `merge-tools.<tool>.premerge=keep-mergediff`.

 * External hooks are now called with `HGPLAIN=1` preset.

 * The `branchmap` cache is updated more intelligently and can be
   significantly faster for repositories with many branches and changesets.


== 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 ==

 * `--force-lock` and `--force-wlock` options on `hg debuglock` command are
   renamed to `--force-free-lock` and `--force-free-wlock` respectively.


== Internal API Changes ==