# registrar.py - utilities to register function for specific purpose

#

#  Copyright FUJIWARA Katsunori <foozy@lares.dti.ne.jp> and others

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

from . import (

    configitems,

    error,

    pycompat,

    util,

)

# unlike the other registered items, config options are neither functions or

# classes. Registering the option is just small function call.

#

# We still add the official API to the registrar module for consistency with

# the other items extensions want might to register.

configitem = configitems.getitemregister

class _funcregistrarbase(object):

    """Base of decorator to register a function for specific purpose

    This decorator stores decorated functions into own dict 'table'.

    The least derived class can be defined by overriding 'formatdoc',

    for example::

        class keyword(_funcregistrarbase):

            _docformat = ":%s: %s"

    This should be used as below:

        keyword = registrar.keyword()

        @keyword('bar')

        def barfunc(*args, **kwargs):

            '''Explanation of bar keyword ....

            '''

            pass

    In this case:

    - 'barfunc' is stored as 'bar' in '_table' of an instance 'keyword' above

    - 'barfunc.__doc__' becomes ":bar: Explanation of bar keyword"

    """

    def __init__(self, table=None):

        if table is None:

            self._table = {}

        else:

            self._table = table

    def __call__(self, decl, *args, **kwargs):

        return lambda func: self._doregister(func, decl, *args, **kwargs)

    def _doregister(self, func, decl, *args, **kwargs):

        name = self._getname(decl)

        if name in self._table:

            msg = 'duplicate registration for name: "%s"' % name

            raise error.ProgrammingError(msg)

        if func.__doc__ and not util.safehasattr(func, '_origdoc'):

            doc = pycompat.sysbytes(func.__doc__).strip()

            func._origdoc = doc

            func.__doc__ = pycompat.sysstr(self._formatdoc(decl, doc))

        self._table[name] = func

        self._extrasetup(name, func, *args, **kwargs)

        return func

    def _parsefuncdecl(self, decl):

        """Parse function declaration and return the name of function in it

        """

        i = decl.find('(')

        if i >= 0:

            return decl[:i]

        else:

            return decl

    def _getname(self, decl):

        """Return the name of the registered function from decl

        Derived class should override this, if it allows more

        descriptive 'decl' string than just a name.

        """

        return decl

    _docformat = None

    def _formatdoc(self, decl, doc):

        """Return formatted document of the registered function for help

        'doc' is '__doc__.strip()' of the registered function.

        """

        return self._docformat % (decl, doc)

    def _extrasetup(self, name, func):

        """Execute exra setup for registered function, if needed

        """

class command(_funcregistrarbase):

    """Decorator to register a command function to table

    This class receives a command table as its argument. The table should

    be a dict.

    The created object can be used as a decorator for adding commands to

    that command table. This accepts multiple arguments to define a command.

    The first argument is the command name (as bytes).

    The `options` keyword argument is an iterable of tuples defining command

    arguments. See ``mercurial.fancyopts.fancyopts()`` for the format of each

    tuple.

    The `synopsis` argument defines a short, one line summary of how to use the

    command. This shows up in the help output.

    There are three arguments that control what repository (if any) is found

    and passed to the decorated function: `norepo`, `optionalrepo`, and

    `inferrepo`.

    The `norepo` argument defines whether the command does not require a

    local repository. Most commands operate against a repository, thus the

    default is False. When True, no repository will be passed.

    The `optionalrepo` argument defines whether the command optionally requires

    a local repository. If no repository can be found, None will be passed

    to the decorated function.

    The `inferrepo` argument defines whether to try to find a repository from

    the command line arguments. If True, arguments will be examined for

    potential repository locations. See ``findrepo()``. If a repository is

    found, it will be used and passed to the decorated function.

    The `intents` argument defines a set of intended actions or capabilities

    the command is taking. These intents can be used to affect the construction

    of the repository object passed to the command. For example, commands

    declaring that they are read-only could receive a repository that doesn't

    have any methods allowing repository mutation. Other intents could be used

    to prevent the command from running if the requested intent could not be

    fulfilled.

    If `helpcategory` is set (usually to one of the constants in the help

    module), the command will be displayed under that category in the help's

    list of commands.

    The following intents are defined:

    readonly

       The command is read-only

    The signature of the decorated function looks like this:

        def cmd(ui[, repo] [, <args>] [, <options>])

      `repo` is required if `norepo` is False.

      `<args>` are positional args (or `*args`) arguments, of non-option

      arguments from the command line.

      `<options>` are keyword arguments (or `**options`) of option arguments

      from the command line.

    See the WritingExtensions and MercurialApi documentation for more exhaustive

    descriptions and examples.

    """

    # Command categories for grouping them in help output.

    CATEGORY_NONE = 'none'

    def _doregister(self, func, name, options=(), synopsis=None,

                    norepo=False, optionalrepo=False, inferrepo=False,

                    intents=None, helpcategory=None):

        func.norepo = norepo

        func.optionalrepo = optionalrepo

        func.inferrepo = inferrepo

        func.intents = intents or set()

        func.helpcategory = helpcategory

        if synopsis:

            self._table[name] = func, list(options), synopsis

        else:

            self._table[name] = func, list(options)

        return func

INTENT_READONLY = b'readonly'

class revsetpredicate(_funcregistrarbase):

    """Decorator to register revset predicate

    Usage::

        revsetpredicate = registrar.revsetpredicate()

        @revsetpredicate('mypredicate(arg1, arg2[, arg3])')

        def mypredicatefunc(repo, subset, x):

            '''Explanation of this revset predicate ....

            '''

            pass

    The first string argument is used also in online help.

    Optional argument 'safe' indicates whether a predicate is safe for

    DoS attack (False by default).

    Optional argument 'takeorder' indicates whether a predicate function

    takes ordering policy as the last argument.

    Optional argument 'weight' indicates the estimated run-time cost, useful

    for static optimization, default is 1. Higher weight means more expensive.

    Usually, revsets that are fast and return only one revision has a weight of

    0.5 (ex. a symbol); revsets with O(changelog) complexity and read only the

    changelog have weight 10 (ex. author); revsets reading manifest deltas have

    weight 30 (ex. adds); revset reading manifest contents have weight 100

    (ex. contains). Note: those values are flexible. If the revset has a

    same big-O time complexity as 'contains', but with a smaller constant, it

    might have a weight of 90.

    'revsetpredicate' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'revsetpredicate' is used for

    decorating in extension.

    Otherwise, explicit 'revset.loadpredicate()' is needed.

    """

    _getname = _funcregistrarbase._parsefuncdecl

    _docformat = "``%s``\n    %s"

    def _extrasetup(self, name, func, safe=False, takeorder=False, weight=1):

        func._safe = safe

        func._takeorder = takeorder

        func._weight = weight

class filesetpredicate(_funcregistrarbase):

    """Decorator to register fileset predicate

    Usage::

        filesetpredicate = registrar.filesetpredicate()

        @filesetpredicate('mypredicate()')

        def mypredicatefunc(mctx, x):

            '''Explanation of this fileset predicate ....

            '''

            pass

    The first string argument is used also in online help.

    Optional argument 'callstatus' indicates whether a predicate

     implies 'matchctx.status()' at runtime or not (False, by

     default).

    Optional argument 'weight' indicates the estimated run-time cost, useful

    for static optimization, default is 1. Higher weight means more expensive.

    There are predefined weights in the 'filesetlang' module.

    ====== =============================================================

    Weight Description and examples

    ====== =============================================================

    0.5    basic match patterns (e.g. a symbol)

    10     computing status (e.g. added()) or accessing a few files

    30     reading file content for each (e.g. grep())

    50     scanning working directory (ignored())

    ====== =============================================================

    'filesetpredicate' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'filesetpredicate' is used for

    decorating in extension.

    Otherwise, explicit 'fileset.loadpredicate()' is needed.

    """

    _getname = _funcregistrarbase._parsefuncdecl

    _docformat = "``%s``\n    %s"

    def _extrasetup(self, name, func, callstatus=False, weight=1):

        func._callstatus = callstatus

        func._weight = weight

class _templateregistrarbase(_funcregistrarbase):

    """Base of decorator to register functions as template specific one

    """

    _docformat = ":%s: %s"

class templatekeyword(_templateregistrarbase):

    """Decorator to register template keyword

    Usage::

        templatekeyword = registrar.templatekeyword()

        # new API (since Mercurial 4.6)

        @templatekeyword('mykeyword', requires={'repo', 'ctx'})

        def mykeywordfunc(context, mapping):

            '''Explanation of this template keyword ....

            '''

            pass

        # old API (DEPRECATED)

        @templatekeyword('mykeyword')

        def mykeywordfunc(repo, ctx, templ, cache, revcache, **args):

            '''Explanation of this template keyword ....

            '''

            pass

    The first string argument is used also in online help.

    Optional argument 'requires' should be a collection of resource names

    which the template keyword depends on. This also serves as a flag to

    switch to the new API. If 'requires' is unspecified, all template

    keywords and resources are expanded to the function arguments.

    'templatekeyword' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'templatekeyword' is used for

    decorating in extension.

    Otherwise, explicit 'templatekw.loadkeyword()' is needed.

    """

    def _extrasetup(self, name, func, requires=None):

        func._requires = requires

class templatefilter(_templateregistrarbase):

    """Decorator to register template filer

    Usage::

        templatefilter = registrar.templatefilter()

        @templatefilter('myfilter', intype=bytes)

        def myfilterfunc(text):

            '''Explanation of this template filter ....

            '''

            pass

    The first string argument is used also in online help.

    Optional argument 'intype' defines the type of the input argument,

    which should be (bytes, int, templateutil.date, or None for any.)

    'templatefilter' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'templatefilter' is used for

    decorating in extension.

    Otherwise, explicit 'templatefilters.loadkeyword()' is needed.

    """

    def _extrasetup(self, name, func, intype=None):

        func._intype = intype

class templatefunc(_templateregistrarbase):

    """Decorator to register template function

    Usage::

        templatefunc = registrar.templatefunc()

        @templatefunc('myfunc(arg1, arg2[, arg3])', argspec='arg1 arg2 arg3',

                      requires={'ctx'})

        def myfuncfunc(context, mapping, args):

            '''Explanation of this template function ....

            '''

            pass

    The first string argument is used also in online help.

    If optional 'argspec' is defined, the function will receive 'args' as

    a dict of named arguments. Otherwise 'args' is a list of positional

    arguments.

    Optional argument 'requires' should be a collection of resource names

    which the template function depends on.

    'templatefunc' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'templatefunc' is used for

    decorating in extension.

    Otherwise, explicit 'templatefuncs.loadfunction()' is needed.

    """

    _getname = _funcregistrarbase._parsefuncdecl

    def _extrasetup(self, name, func, argspec=None, requires=()):

        func._argspec = argspec

        func._requires = requires

class internalmerge(_funcregistrarbase):

    """Decorator to register in-process merge tool

    Usage::

        internalmerge = registrar.internalmerge()

        @internalmerge('mymerge', internalmerge.mergeonly,

                       onfailure=None, precheck=None,

                       binary=False, symlink=False):

        def mymergefunc(repo, mynode, orig, fcd, fco, fca,

                        toolconf, files, labels=None):

            '''Explanation of this internal merge tool ....

            '''

            return 1, False # means "conflicted", "no deletion needed"

    The first string argument is used to compose actual merge tool name,

    ":name" and "internal:name" (the latter is historical one).

    The second argument is one of merge types below:

    ========== ======== ======== =========

    merge type precheck premerge fullmerge

    ========== ======== ======== =========

    nomerge     x        x        x

    mergeonly   o        x        o

    fullmerge   o        o        o

    ========== ======== ======== =========

    Optional argument 'onfailure' is the format of warning message

    to be used at failure of merging (target filename is specified

    at formatting). Or, None or so, if warning message should be

    suppressed.

    Optional argument 'precheck' is the function to be used

    before actual invocation of internal merge tool itself.

    It takes as same arguments as internal merge tool does, other than

    'files' and 'labels'. If it returns false value, merging is aborted

    immediately (and file is marked as "unresolved").

    Optional argument 'binary' is a binary files capability of internal

    merge tool. 'nomerge' merge type implies binary=True.

    Optional argument 'symlink' is a symlinks capability of inetrnal

    merge function. 'nomerge' merge type implies symlink=True.

    'internalmerge' instance in example above can be used to

    decorate multiple functions.

    Decorated functions are registered automatically at loading

    extension, if an instance named as 'internalmerge' is used for

    decorating in extension.

    Otherwise, explicit 'filemerge.loadinternalmerge()' is needed.

    """

    _docformat = "``:%s``\n    %s"

    # merge type definitions:

    nomerge = None

    mergeonly = 'mergeonly'  # just the full merge, no premerge

    fullmerge = 'fullmerge'  # both premerge and merge

    def _extrasetup(self, name, func, mergetype,

                    onfailure=None, precheck=None,

                    binary=False, symlink=False):

        func.mergetype = mergetype

        func.onfailure = onfailure

        func.precheck = precheck

        binarycap = binary or mergetype == self.nomerge

        symlinkcap = symlink or mergetype == self.nomerge

        # actual capabilities, which this internal merge tool has

        func.capabilities = {"binary": binarycap, "symlink": symlinkcap}