templatekw: change default value of 'requires' to ()

Since we dropped support for the old-style template keywords, we no longer
have to distinguish None (old-style) and an empty requirement (new-style).

mercurial/registrar.py

@@ -1,503 +1,501
 # registrar.py - utilities to register function for specific purpose
 #
 #  Copyright FUJIWARA Katsunori <[e-mail]> 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 _merge(self, registrarbase):
         """Merge the entries of the given registrar object into this one.
 
         The other registrar object must not contain any entries already in the
         current one, or a ProgrammmingError is raised.  Additionally, the types
         of the two registrars must match.
         """
         if not isinstance(registrarbase, type(self)):
             msg = "cannot merge different types of registrar"
             raise error.ProgrammingError(msg)
 
         dups = set(registrarbase._table).intersection(self._table)
 
         if dups:
             msg = 'duplicate registration for names: "%s"' % '", "'.join(dups)
             raise error.ProgrammingError(msg)
 
         self._table.update(registrarbase._table)
 
     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.
     # These can also be specified for aliases, like:
     # [alias]
     # myalias = something
     # myalias:category = repo
     CATEGORY_REPO_CREATION = 'repo'
     CATEGORY_REMOTE_REPO_MANAGEMENT = 'remote'
     CATEGORY_COMMITTING = 'commit'
     CATEGORY_CHANGE_MANAGEMENT = 'management'
     CATEGORY_CHANGE_ORGANIZATION = 'organization'
     CATEGORY_FILE_CONTENTS = 'files'
     CATEGORY_CHANGE_NAVIGATION  = 'navigation'
     CATEGORY_WORKING_DIRECTORY = 'wdir'
     CATEGORY_IMPORT_EXPORT = 'import'
     CATEGORY_MAINTENANCE = 'maintenance'
     CATEGORY_HELP = 'help'
     CATEGORY_MISC = 'misc'
     CATEGORY_NONE = 'none'
 
     def _doregister(self, func, name, options=(), synopsis=None,
                     norepo=False, optionalrepo=False, inferrepo=False,
                     intents=None, helpcategory=None, helpbasic=False):
         func.norepo = norepo
         func.optionalrepo = optionalrepo
         func.inferrepo = inferrepo
         func.intents = intents or set()
         func.helpcategory = helpcategory
         func.helpbasic = helpbasic
         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
 
     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.
+    which the template keyword depends on.
 
     '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):
+    def _extrasetup(self, name, func, requires=()):
         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}