view mercurial/help/phases.txt @ 40324:6637b079ae45

lfs: autoload the extension when cloning from repo with lfs enabled

This is based on a patch by Gregory Szorc.  I made small adjustments to
clean up the messaging when the server has the extension enabled, but the
client has it disabled (to prevent autoloading).  Additionally, I added
a second server capability to distinguish between the server having the
extension enabled, and the server having LFS commits.  This helps prevent
unnecessary requirement propagation- the client shouldn't add a requirement
that the server doesn't have, just because the server had the extension
loaded.  The TODO I had about advertising a capability when the server can
natively serve up blobs isn't relevant anymore (we've had 2 releases that
support this), so I dropped it.

Currently, we lazily add the "lfs" requirement to a repo when we first
encounter LFS data. Due to a pretxnchangegroup hook that looks for LFS
data, this can happen at the end of clone.

Now that we have more control over how repositories are created, we can
do better.

This commit adds a repo creation option to add the "lfs" requirement.
hg.clone() sets this creation option if the remote peer is advertising
lfs usage (as opposed to just support needed to push).

So, what this change effectively does is have cloned repos
automatically inherit the "lfs" requirement.

Differential Revision: https://phab.mercurial-scm.org/D5130

What are phases?
================

Phases are a system for tracking which changesets have been or should
be shared. This helps prevent common mistakes when modifying history
(for instance, with the mq or rebase extensions).

Each changeset in a repository is in one of the following phases:

 - public : changeset is visible on a public server
 - draft : changeset is not yet published
 - secret : changeset should not be pushed, pulled, or cloned

These phases are ordered (public < draft < secret) and no changeset
can be in a lower phase than its ancestors. For instance, if a
changeset is public, all its ancestors are also public. Lastly,
changeset phases should only be changed towards the public phase.

How are phases managed?
=======================

For the most part, phases should work transparently. By default, a
changeset is created in the draft phase and is moved into the public
phase when it is pushed to another repository.

Once changesets become public, extensions like mq and rebase will
refuse to operate on them to prevent creating duplicate changesets.
Phases can also be manually manipulated with the :hg:`phase` command
if needed. See :hg:`help -v phase` for examples.

To make your commits secret by default, put this in your
configuration file::

  [phases]
  new-commit = secret

Phases and servers
==================

Normally, all servers are ``publishing`` by default. This means::

 - all draft changesets that are pulled or cloned appear in phase
 public on the client

 - all draft changesets that are pushed appear as public on both
 client and server

 - secret changesets are neither pushed, pulled, or cloned

.. note::

  Pulling a draft changeset from a publishing server does not mark it
  as public on the server side due to the read-only nature of pull.

Sometimes it may be desirable to push and pull changesets in the draft
phase to share unfinished work. This can be done by setting a
repository to disable publishing in its configuration file::

  [phases]
  publish = False

See :hg:`help config` for more information on configuration files.

.. note::

  Servers running older versions of Mercurial are treated as
  publishing.

.. note::

   Changesets in secret phase are not exchanged with the server. This
   applies to their content: file names, file contents, and changeset
   metadata. For technical reasons, the identifier (e.g. d825e4025e39)
   of the secret changeset may be communicated to the server.


Examples
========

 - list changesets in draft or secret phase::

     hg log -r "not public()"

 - change all secret changesets to draft::

     hg phase --draft "secret()"

 - forcibly move the current changeset and descendants from public to draft::

     hg phase --force --draft .

 - show a list of changeset revisions and each corresponding phase::

     hg log --template "{rev} {phase}\n"

 - resynchronize draft changesets relative to a remote repository::

     hg phase -fd "outgoing(URL)"

See :hg:`help phase` for more information on manually manipulating phases.