git: skeleton of a new extension to _directly_ operate on git repos
This is based in part of work I did years ago in hgit, but it's mostly
new code since I'm using pygit2 instead of dulwich and the hg storage
interfaces have improved. Some cleanup of old hgit code by Pulkit,
which I greatly appreciate.
test-git-interop.t does not cover a whole lot of cases, but it
passes. It includes status, diff, making a new commit, and `hg annotate`
working on the git repository.
This is _not_ (yet) production quality code: this is an
experiment. Known technical debt lurking in this implementation:
* Writing bookmarks just totally ignores transactions.
* The way progress is threaded down into the gitstore is awful.
* Ideally we'd find a way to incrementally reindex DAGs. I'm not sure
how to do that efficiently, so we might need a "known only fast-forwards"
mode on the DAG indexer for use on `hg commit` and friends.
* We don't even _try_ to do anything reasonable for `hg pull` or `hg push`.
* Mercurial need an interface for the changelog type.
Tests currently require git 2.24 as far as I'm aware: `git status` has
some changed output that I didn't try and handle in a compatible way.
This patch has produced some interesting cleanups, most recently on
the manifest type. I expect continuing down this road will produce
other meritorious cleanups throughout our code.
Differential Revision: https://phab.mercurial-scm.org/D6734
Valid URLs are of the form::
local/filesystem/path[#revision]
file://local/filesystem/path[#revision]
http://[user[:pass]@]host[:port]/[path][#revision]
https://[user[:pass]@]host[:port]/[path][#revision]
ssh://[user@]host[:port]/[path][#revision]
Paths in the local filesystem can either point to Mercurial
repositories or to bundle files (as created by :hg:`bundle` or
:hg:`incoming --bundle`). See also :hg:`help paths`.
An optional identifier after # indicates a particular branch, tag, or
changeset to use from the remote repository. See also :hg:`help
revisions`.
Some features, such as pushing to http:// and https:// URLs are only
possible if the feature is explicitly enabled on the remote Mercurial
server.
Note that the security of HTTPS URLs depends on proper configuration of
web.cacerts.
Some notes about using SSH with Mercurial:
- SSH requires an accessible shell account on the destination machine
and a copy of hg in the remote path or specified with remotecmd.
- path is relative to the remote user's home directory by default. Use
an extra slash at the start of a path to specify an absolute path::
ssh://example.com//tmp/repository
- Mercurial doesn't use its own compression via SSH; the right thing
to do is to configure it in your ~/.ssh/config, e.g.::
Host *.mylocalnetwork.example.com
Compression no
Host *
Compression yes
Alternatively specify "ssh -C" as your ssh command in your
configuration file or with the --ssh command line option.
These URLs can all be stored in your configuration file with path
aliases under the [paths] section like so::
[paths]
alias1 = URL1
alias2 = URL2
...
You can then use the alias for any command that uses a URL (for
example :hg:`pull alias1` will be treated as :hg:`pull URL1`).
Two path aliases are special because they are used as defaults when
you do not provide the URL to a command:
default:
When you create a repository with hg clone, the clone command saves
the location of the source repository as the new repository's
'default' path. This is then used when you omit path from push- and
pull-like commands (including incoming and outgoing).
default-push:
The push command will look for a path named 'default-push', and
prefer it over 'default' if both are defined.