~bzr-pqm/bzr/bzr.dev

*************************

What's New in Bazaar 2.4?

*************************

Bazaar 2.4 is still under development, and will be released in August 2011.

This document accumulates a high level summary of what's changed.  See the

:doc:`../release-notes/index` for a full list.

Users are encouraged to upgrade from the other stable series.  This

document outlines the improvements in Bazaar 2.4 vs Bazaar 2.3. As well as

summarizing improvements made to the core product, it highlights

enhancements within the broader Bazaar world of potential interest to

those upgrading.

Bazaar 2.4.0 is fully compatible both locally and on the network with 2.0,

2.1, 2.2 and 2.3, and can read and write repositories generated by all

previous versions.

Dropping Python2.4 and Python2.5 support

****************************************

Bazaar 2.4.0 is the first version of bzr to drop support for python

versions before 2.6. The 2.3 series will still be maintained in bugfix

mode for people who need older versions of python. This allows us to clean

up the syntax in our files, as well as start looking into python3

compatibility.

External merge tools

********************

External merge tool configuration has been added to ``bzr`` core. The name

and commandline of one or more external merge tools can be defined in

bazaar.conf. See the help topic ``configuration`` for more details.

Tagged revisions are copied

***************************

When tags are copied from a branch, the associated revisions are now copied

too.  Previously operations like branching, merging or pulling might have

copied new tags visible in ``bzr tags``, but not copied the revisions.  Now

revisions from tags will always be present, so that operations like ``bzr

log -r tag:foo`` will always work.

Deprecated command synonyms

***************************

Two built-in synonyms for ``bzr branch`` have been deprecated: ``clone`` and

``get``.

Configuration files

*******************

Option values can now refer to other options in the same configuration file by

enclosing them in curly brackets (``{option}``). This is an opt-in feature

during the beta period controlled by the ``bzr.config.expand`` option that

should be declared in ``bazaar.conf`` and no other file.

Changelog merge plugin

**********************

The ``changelog_merge`` plugin has been added.  It provides a merge hook

to automate merging of changes to ``ChangeLog`` files in GNU's change log

format.  Refer to ``bzr help changelog_merge`` for documentation on how to

enable it and what it can do.

Faster operations on Large Trees

********************************

Many bzr commands used to run into pathological behavior on large trees

(>10k files), reading the inventory data in random order causing cache

thrashing. Various other tweaks have been applied with feedback from large

trees. A possibly incomplete list is as follows for running commands on a

70k file tree::

    bzr-2.3 bzr-2.4 action

    3m39s   1m03s   bzr co --lightweight

      38s      6s   bzr revert

    4m47s     27s   bzr merge

    4m58s     32s   bzr up

Faster stacked branches

***********************

Creating a stacked branch from a smart server with ``bzr branch

--stacked`` is a bit faster now.  For small branches it does 20% fewer

network roundtrips.  Other operations where a local branch is stacked on a

branch hosted on a smart server will also benefit.

Further information

*******************

For more detailed information on the changes made, see the the

:doc:`../release-notes/index` for:

* the interim bzr `milestones <https://launchpad.net/bzr/2.4>`_

* the plugins you use.

For a summary of changes made in earlier releases, see:

* :doc:`whats-new-in-2.1`

* :doc:`whats-new-in-2.2`

* :doc:`whats-new-in-2.3`

..

   vim: tw=74 ft=rst ff=unix