view mercurial/help/patterns.txt @ 26755:bb0b955d050d

streamclone: support for producing and consuming stream clone bundles

Up to this point, stream clones only existed as a dynamically generated
data format produced and consumed during streaming clones. In order to
support this efficient cloning format with the clone bundles feature, we
need a more formal, on disk representation of the streaming clone data.

This patch introduces a new "bundle" type for streaming clones. Unlike
existing bundles, it does not contain changegroup data. It does,
however, share the same concepts like the 4 byte header which identifies
the type of data that follows and the 2 byte abbreviation for
compression types (of which only "UN" is currently supported).

The new bundle format is essentially the existing stream clone version 1
data format with some headers at the beginning.

Content negotiation at stream clone request time checked for repository
format/requirements compatibility before initiating a stream clone. We
can't do active content negotiation when using clone bundles. So, we put
this set of requirements inside the payload so consumers have a built-in
mechanism for checking compatibility before reading and applying lots of
data. Of course, we will also advertise this requirements set in clone
bundles. But that's for another patch.

We currently don't have a mechanism to produce and consume this new
bundle format. This will be implemented in upcoming patches.

It's worth noting that if a legacy client attempts to `hg unbundle` a
stream clone bundle (with the "HGS1" header), it will abort with:
"unknown bundle version S1," which seems appropriate.

Mercurial accepts several notations for identifying one or more files
at a time.

By default, Mercurial treats filenames as shell-style extended glob
patterns.

Alternate pattern notations must be specified explicitly.

.. note::

  Patterns specified in ``.hgignore`` are not rooted.
  Please see :hg:`help hgignore` for details.

To use a plain path name without any pattern matching, start it with
``path:``. These path names must completely match starting at the
current repository root.

To use an extended glob, start a name with ``glob:``. Globs are rooted
at the current directory; a glob such as ``*.c`` will only match files
in the current directory ending with ``.c``.

The supported glob syntax extensions are ``**`` to match any string
across path separators and ``{a,b}`` to mean "a or b".

To use a Perl/Python regular expression, start a name with ``re:``.
Regexp pattern matching is anchored at the root of the repository.

To read name patterns from a file, use ``listfile:`` or ``listfile0:``.
The latter expects null delimited patterns while the former expects line
feeds. Each string read from the file is itself treated as a file
pattern.

To read a set of patterns from a file, use ``include:`` or ``subinclude:``.
``include:`` will use all the patterns from the given file and treat them as if
they had been passed in manually.  ``subinclude:`` will only apply the patterns
against files that are under the subinclude file's directory. See :hg:`help
hgignore` for details on the format of these files.

All patterns, except for ``glob:`` specified in command line (not for
``-I`` or ``-X`` options), can match also against directories: files
under matched directories are treated as matched.

Plain examples::

  path:foo/bar   a name bar in a directory named foo in the root
                 of the repository
  path:path:name a file or directory named "path:name"

Glob examples::

  glob:*.c       any name ending in ".c" in the current directory
  *.c            any name ending in ".c" in the current directory
  **.c           any name ending in ".c" in any subdirectory of the
                 current directory including itself.
  foo/*.c        any name ending in ".c" in the directory foo
  foo/**.c       any name ending in ".c" in any subdirectory of foo
                 including itself.

Regexp examples::

  re:.*\.c$      any name ending in ".c", anywhere in the repository

File examples::

  listfile:list.txt  read list from list.txt with one file pattern per line
  listfile0:list.txt read list from list.txt with null byte delimiters

See also :hg:`help filesets`.

Include examples::

  include:path/to/mypatternfile    reads patterns to be applied to all paths
  subinclude:path/to/subignorefile reads patterns specifically for paths in the
                                   subdirectory