view hgext/schemes.py @ 27583:37d50250b696

registrar: add funcregistrar class to register function for specific purpose

This class centralizes the common logic to register function for
specific purpose like below:

    - template keyword, filter and function
    - revset predicate
    - fileset predicate
    - webcommand

'funcregistrar' also formats help document of the function with the
'decl'(aration) specified at the construction.

This can avoid (1) redundancy between 'decl' and help document, and
(2) accidental typo of help document. For example, 'foo' should appear
twice like below, if without such formatting:

    @keyword('foo')
    def foo(....):
        """:foo: Explanation of keyword foo ..."""

Almost all cases needs very simple document formatting like below:

    - "``DECL``\n    EXPLANATION"
    - ":DECL: EXPLANATION"

But webcommand needs a little complicated formatting like:

    /PATH/SPEC
    ----------

    EXPLANATION ....

To make minirst recognize the section header, hyphen line should be as
long as "/PATH/SPEC". It should be arranged by program.

Implementing 'formatdoc()' in derived class can support complicated
formatting in the latter case. But it seems redundant for simple one
in the former case.

Therefore, 'funcregistrar' does:

    - invoke 'self.formatdoc', if it is callable (for the latter case)
    - use it as the format string, otherwise (for the former case)

# Copyright 2009, Alexander Solovyov <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""extend schemes with shortcuts to repository swarms

This extension allows you to specify shortcuts for parent URLs with a
lot of repositories to act like a scheme, for example::

  [schemes]
  py = http://code.python.org/hg/

After that you can use it like::

  hg clone py://trunk/

Additionally there is support for some more complex schemas, for
example used by Google Code::

  [schemes]
  gcode = http://{1}.googlecode.com/hg/

The syntax is taken from Mercurial templates, and you have unlimited
number of variables, starting with ``{1}`` and continuing with
``{2}``, ``{3}`` and so on. This variables will receive parts of URL
supplied, split by ``/``. Anything not specified as ``{part}`` will be
just appended to an URL.

For convenience, the extension adds these schemes by default::

  [schemes]
  py = http://hg.python.org/
  bb = https://bitbucket.org/
  bb+ssh = ssh://[e-mail]/
  gcode = https://{1}.googlecode.com/hg/
  kiln = https://{1}.kilnhg.com/Repo/

You can override a predefined scheme by defining a new scheme with the
same name.
"""

import os, re
from mercurial import extensions, hg, templater, util, error
from mercurial.i18n import _

# Note for extension authors: ONLY specify testedwith = 'internal' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'internal'


class ShortRepository(object):
    def __init__(self, url, scheme, templater):
        self.scheme = scheme
        self.templater = templater
        self.url = url
        try:
            self.parts = max(map(int, re.findall(r'\{(\d+)\}', self.url)))
        except ValueError:
            self.parts = 0

    def __repr__(self):
        return '<ShortRepository: %s>' % self.scheme

    def instance(self, ui, url, create):
        # Should this use the util.url class, or is manual parsing better?
        try:
            url = url.split('://', 1)[1]
        except IndexError:
            raise error.Abort(_("no '://' in scheme url '%s'") % url)
        parts = url.split('/', self.parts)
        if len(parts) > self.parts:
            tail = parts[-1]
            parts = parts[:-1]
        else:
            tail = ''
        context = dict((str(i + 1), v) for i, v in enumerate(parts))
        url = ''.join(self.templater.process(self.url, context)) + tail
        return hg._peerlookup(url).instance(ui, url, create)

def hasdriveletter(orig, path):
    if path:
        for scheme in schemes:
            if path.startswith(scheme + ':'):
                return False
    return orig(path)

schemes = {
    'py': 'http://hg.python.org/',
    'bb': 'https://bitbucket.org/',
    'bb+ssh': 'ssh://[e-mail]/',
    'gcode': 'https://{1}.googlecode.com/hg/',
    'kiln': 'https://{1}.kilnhg.com/Repo/'
    }

def extsetup(ui):
    schemes.update(dict(ui.configitems('schemes')))
    t = templater.engine(lambda x: x)
    for scheme, url in schemes.items():
        if (os.name == 'nt' and len(scheme) == 1 and scheme.isalpha()
            and os.path.exists('%s:\\' % scheme)):
            raise error.Abort(_('custom scheme %s:// conflicts with drive '
                               'letter %s:\\\n') % (scheme, scheme.upper()))
        hg.schemes[scheme] = ShortRepository(url, scheme, t)

    extensions.wrapfunction(util, 'hasdriveletter', hasdriveletter)