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authormonster <monster@ydb.tech>2022-07-07 14:41:37 +0300
committermonster <monster@ydb.tech>2022-07-07 14:41:37 +0300
commit06e5c21a835c0e923506c4ff27929f34e00761c2 (patch)
tree75efcbc6854ef9bd476eb8bf00cc5c900da436a2 /contrib/python/decorator
parent03f024c4412e3aa613bb543cf1660176320ba8f4 (diff)
downloadydb-06e5c21a835c0e923506c4ff27929f34e00761c2.tar.gz
fix ya.make
Diffstat (limited to 'contrib/python/decorator')
-rw-r--r--contrib/python/decorator/.dist-info/METADATA131
-rw-r--r--contrib/python/decorator/.dist-info/top_level.txt1
-rw-r--r--contrib/python/decorator/LICENSE.txt26
-rw-r--r--contrib/python/decorator/README.rst98
-rw-r--r--contrib/python/decorator/decorator.py454
-rw-r--r--contrib/python/decorator/tests/__init__.py0
-rw-r--r--contrib/python/decorator/tests/documentation.py1897
-rw-r--r--contrib/python/decorator/tests/test.py480
8 files changed, 0 insertions, 3087 deletions
diff --git a/contrib/python/decorator/.dist-info/METADATA b/contrib/python/decorator/.dist-info/METADATA
deleted file mode 100644
index fd12277a01..0000000000
--- a/contrib/python/decorator/.dist-info/METADATA
+++ /dev/null
@@ -1,131 +0,0 @@
-Metadata-Version: 2.1
-Name: decorator
-Version: 4.4.2
-Summary: Decorators for Humans
-Home-page: https://github.com/micheles/decorator
-Author: Michele Simionato
-Author-email: michele.simionato@gmail.com
-License: new BSD License
-Keywords: decorators generic utility
-Platform: All
-Classifier: Development Status :: 5 - Production/Stable
-Classifier: Intended Audience :: Developers
-Classifier: License :: OSI Approved :: BSD License
-Classifier: Natural Language :: English
-Classifier: Operating System :: OS Independent
-Classifier: Programming Language :: Python
-Classifier: Programming Language :: Python :: 2
-Classifier: Programming Language :: Python :: 2.6
-Classifier: Programming Language :: Python :: 2.7
-Classifier: Programming Language :: Python :: 3
-Classifier: Programming Language :: Python :: 3.2
-Classifier: Programming Language :: Python :: 3.3
-Classifier: Programming Language :: Python :: 3.4
-Classifier: Programming Language :: Python :: 3.5
-Classifier: Programming Language :: Python :: 3.6
-Classifier: Programming Language :: Python :: 3.7
-Classifier: Programming Language :: Python :: Implementation :: CPython
-Classifier: Topic :: Software Development :: Libraries
-Classifier: Topic :: Utilities
-Requires-Python: >=2.6, !=3.0.*, !=3.1.*
-
-Decorators for Humans
-=====================
-
-The goal of the decorator module is to make it easy to define
-signature-preserving function decorators and decorator factories.
-It also includes an implementation of multiple dispatch and other niceties
-(please check the docs). It is released under a two-clauses
-BSD license, i.e. basically you can do whatever you want with it but I am not
-responsible.
-
-Installation
--------------
-
-If you are lazy, just perform
-
- ``$ pip install decorator``
-
-which will install just the module on your system.
-
-If you prefer to install the full distribution from source, including
-the documentation, clone the `GitHub repo`_ or download the tarball_, unpack it and run
-
- ``$ pip install .``
-
-in the main directory, possibly as superuser.
-
-.. _tarball: https://pypi.org/project/decorator/#files
-.. _GitHub repo: https://github.com/micheles/decorator
-
-Testing
---------
-
-If you have the source code installation you can run the tests with
-
- `$ python src/tests/test.py -v`
-
-or (if you have setuptools installed)
-
- `$ python setup.py test`
-
-Notice that you may run into trouble if in your system there
-is an older version of the decorator module; in such a case remove the
-old version. It is safe even to copy the module `decorator.py` over
-an existing one, since we kept backward-compatibility for a long time.
-
-Repository
----------------
-
-The project is hosted on GitHub. You can look at the source here:
-
- https://github.com/micheles/decorator
-
-Documentation
----------------
-
-The documentation has been moved to https://github.com/micheles/decorator/blob/master/docs/documentation.md
-
-From there you can get a PDF version by simply using the print
-functionality of your browser.
-
-Here is the documentation for previous versions of the module:
-
-https://github.com/micheles/decorator/blob/4.3.2/docs/tests.documentation.rst
-https://github.com/micheles/decorator/blob/4.2.1/docs/tests.documentation.rst
-https://github.com/micheles/decorator/blob/4.1.2/docs/tests.documentation.rst
-https://github.com/micheles/decorator/blob/4.0.0/documentation.rst
-https://github.com/micheles/decorator/blob/3.4.2/documentation.rst
-
-For the impatient
------------------
-
-Here is an example of how to define a family of decorators tracing slow
-operations:
-
-.. code-block:: python
-
- from decorator import decorator
-
- @decorator
- def warn_slow(func, timelimit=60, *args, **kw):
- t0 = time.time()
- result = func(*args, **kw)
- dt = time.time() - t0
- if dt > timelimit:
- logging.warn('%s took %d seconds', func.__name__, dt)
- else:
- logging.info('%s took %d seconds', func.__name__, dt)
- return result
-
- @warn_slow # warn if it takes more than 1 minute
- def preprocess_input_files(inputdir, tempdir):
- ...
-
- @warn_slow(timelimit=600) # warn if it takes more than 10 minutes
- def run_calculation(tempdir, outdir):
- ...
-
-Enjoy!
-
-
diff --git a/contrib/python/decorator/.dist-info/top_level.txt b/contrib/python/decorator/.dist-info/top_level.txt
deleted file mode 100644
index 3fe18a4d1c..0000000000
--- a/contrib/python/decorator/.dist-info/top_level.txt
+++ /dev/null
@@ -1 +0,0 @@
-decorator
diff --git a/contrib/python/decorator/LICENSE.txt b/contrib/python/decorator/LICENSE.txt
deleted file mode 100644
index b0ade0487e..0000000000
--- a/contrib/python/decorator/LICENSE.txt
+++ /dev/null
@@ -1,26 +0,0 @@
-Copyright (c) 2005-2018, Michele Simionato
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are
-met:
-
- Redistributions of source code must retain the above copyright
- notice, this list of conditions and the following disclaimer.
- Redistributions in bytecode form must reproduce the above copyright
- notice, this list of conditions and the following disclaimer in
- the documentation and/or other materials provided with the
- distribution.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
-INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
-BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
-OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
-TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
-USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
-DAMAGE.
diff --git a/contrib/python/decorator/README.rst b/contrib/python/decorator/README.rst
deleted file mode 100644
index f56161c74a..0000000000
--- a/contrib/python/decorator/README.rst
+++ /dev/null
@@ -1,98 +0,0 @@
-Decorators for Humans
-=====================
-
-The goal of the decorator module is to make it easy to define
-signature-preserving function decorators and decorator factories.
-It also includes an implementation of multiple dispatch and other niceties
-(please check the docs). It is released under a two-clauses
-BSD license, i.e. basically you can do whatever you want with it but I am not
-responsible.
-
-Installation
--------------
-
-If you are lazy, just perform
-
- ``$ pip install decorator``
-
-which will install just the module on your system.
-
-If you prefer to install the full distribution from source, including
-the documentation, clone the `GitHub repo`_ or download the tarball_, unpack it and run
-
- ``$ pip install .``
-
-in the main directory, possibly as superuser.
-
-.. _tarball: https://pypi.org/project/decorator/#files
-.. _GitHub repo: https://github.com/micheles/decorator
-
-Testing
---------
-
-If you have the source code installation you can run the tests with
-
- `$ python src/tests/test.py -v`
-
-or (if you have setuptools installed)
-
- `$ python setup.py test`
-
-Notice that you may run into trouble if in your system there
-is an older version of the decorator module; in such a case remove the
-old version. It is safe even to copy the module `decorator.py` over
-an existing one, since we kept backward-compatibility for a long time.
-
-Repository
----------------
-
-The project is hosted on GitHub. You can look at the source here:
-
- https://github.com/micheles/decorator
-
-Documentation
----------------
-
-The documentation has been moved to https://github.com/micheles/decorator/blob/master/docs/documentation.md
-
-From there you can get a PDF version by simply using the print
-functionality of your browser.
-
-Here is the documentation for previous versions of the module:
-
-https://github.com/micheles/decorator/blob/4.3.2/docs/tests.documentation.rst
-https://github.com/micheles/decorator/blob/4.2.1/docs/tests.documentation.rst
-https://github.com/micheles/decorator/blob/4.1.2/docs/tests.documentation.rst
-https://github.com/micheles/decorator/blob/4.0.0/documentation.rst
-https://github.com/micheles/decorator/blob/3.4.2/documentation.rst
-
-For the impatient
------------------
-
-Here is an example of how to define a family of decorators tracing slow
-operations:
-
-.. code-block:: python
-
- from decorator import decorator
-
- @decorator
- def warn_slow(func, timelimit=60, *args, **kw):
- t0 = time.time()
- result = func(*args, **kw)
- dt = time.time() - t0
- if dt > timelimit:
- logging.warn('%s took %d seconds', func.__name__, dt)
- else:
- logging.info('%s took %d seconds', func.__name__, dt)
- return result
-
- @warn_slow # warn if it takes more than 1 minute
- def preprocess_input_files(inputdir, tempdir):
- ...
-
- @warn_slow(timelimit=600) # warn if it takes more than 10 minutes
- def run_calculation(tempdir, outdir):
- ...
-
-Enjoy!
diff --git a/contrib/python/decorator/decorator.py b/contrib/python/decorator/decorator.py
deleted file mode 100644
index b1f8b567e9..0000000000
--- a/contrib/python/decorator/decorator.py
+++ /dev/null
@@ -1,454 +0,0 @@
-# ######################### LICENSE ############################ #
-
-# Copyright (c) 2005-2018, Michele Simionato
-# All rights reserved.
-
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions are
-# met:
-
-# Redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer.
-# Redistributions in bytecode form must reproduce the above copyright
-# notice, this list of conditions and the following disclaimer in
-# the documentation and/or other materials provided with the
-# distribution.
-
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-# HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
-# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
-# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
-# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
-# TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
-# USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
-# DAMAGE.
-
-"""
-Decorator module, see http://pypi.python.org/pypi/decorator
-for the documentation.
-"""
-from __future__ import print_function
-
-import re
-import sys
-import inspect
-import operator
-import itertools
-import collections
-
-__version__ = '4.4.2'
-
-if sys.version_info >= (3,):
- from inspect import getfullargspec
-
- def get_init(cls):
- return cls.__init__
-else:
- FullArgSpec = collections.namedtuple(
- 'FullArgSpec', 'args varargs varkw defaults '
- 'kwonlyargs kwonlydefaults annotations')
-
- def getfullargspec(f):
- "A quick and dirty replacement for getfullargspec for Python 2.X"
- return FullArgSpec._make(inspect.getargspec(f) + ([], None, {}))
-
- def get_init(cls):
- return cls.__init__.__func__
-
-try:
- iscoroutinefunction = inspect.iscoroutinefunction
-except AttributeError:
- # let's assume there are no coroutine functions in old Python
- def iscoroutinefunction(f):
- return False
-try:
- from inspect import isgeneratorfunction
-except ImportError:
- # assume no generator function in old Python versions
- def isgeneratorfunction(caller):
- return False
-
-
-DEF = re.compile(r'\s*def\s*([_\w][_\w\d]*)\s*\(')
-
-
-# basic functionality
-class FunctionMaker(object):
- """
- An object with the ability to create functions with a given signature.
- It has attributes name, doc, module, signature, defaults, dict and
- methods update and make.
- """
-
- # Atomic get-and-increment provided by the GIL
- _compile_count = itertools.count()
-
- # make pylint happy
- args = varargs = varkw = defaults = kwonlyargs = kwonlydefaults = ()
-
- def __init__(self, func=None, name=None, signature=None,
- defaults=None, doc=None, module=None, funcdict=None):
- self.shortsignature = signature
- if func:
- # func can be a class or a callable, but not an instance method
- self.name = func.__name__
- if self.name == '<lambda>': # small hack for lambda functions
- self.name = '_lambda_'
- self.doc = func.__doc__
- self.module = func.__module__
- if inspect.isfunction(func):
- argspec = getfullargspec(func)
- self.annotations = getattr(func, '__annotations__', {})
- for a in ('args', 'varargs', 'varkw', 'defaults', 'kwonlyargs',
- 'kwonlydefaults'):
- setattr(self, a, getattr(argspec, a))
- for i, arg in enumerate(self.args):
- setattr(self, 'arg%d' % i, arg)
- allargs = list(self.args)
- allshortargs = list(self.args)
- if self.varargs:
- allargs.append('*' + self.varargs)
- allshortargs.append('*' + self.varargs)
- elif self.kwonlyargs:
- allargs.append('*') # single star syntax
- for a in self.kwonlyargs:
- allargs.append('%s=None' % a)
- allshortargs.append('%s=%s' % (a, a))
- if self.varkw:
- allargs.append('**' + self.varkw)
- allshortargs.append('**' + self.varkw)
- self.signature = ', '.join(allargs)
- self.shortsignature = ', '.join(allshortargs)
- self.dict = func.__dict__.copy()
- # func=None happens when decorating a caller
- if name:
- self.name = name
- if signature is not None:
- self.signature = signature
- if defaults:
- self.defaults = defaults
- if doc:
- self.doc = doc
- if module:
- self.module = module
- if funcdict:
- self.dict = funcdict
- # check existence required attributes
- assert hasattr(self, 'name')
- if not hasattr(self, 'signature'):
- raise TypeError('You are decorating a non function: %s' % func)
-
- def update(self, func, **kw):
- "Update the signature of func with the data in self"
- func.__name__ = self.name
- func.__doc__ = getattr(self, 'doc', None)
- func.__dict__ = getattr(self, 'dict', {})
- func.__defaults__ = self.defaults
- func.__kwdefaults__ = self.kwonlydefaults or None
- func.__annotations__ = getattr(self, 'annotations', None)
- try:
- frame = sys._getframe(3)
- except AttributeError: # for IronPython and similar implementations
- callermodule = '?'
- else:
- callermodule = frame.f_globals.get('__name__', '?')
- func.__module__ = getattr(self, 'module', callermodule)
- func.__dict__.update(kw)
-
- def make(self, src_templ, evaldict=None, addsource=False, **attrs):
- "Make a new function from a given template and update the signature"
- src = src_templ % vars(self) # expand name and signature
- evaldict = evaldict or {}
- mo = DEF.search(src)
- if mo is None:
- raise SyntaxError('not a valid function template\n%s' % src)
- name = mo.group(1) # extract the function name
- names = set([name] + [arg.strip(' *') for arg in
- self.shortsignature.split(',')])
- for n in names:
- if n in ('_func_', '_call_'):
- raise NameError('%s is overridden in\n%s' % (n, src))
-
- if not src.endswith('\n'): # add a newline for old Pythons
- src += '\n'
-
- # Ensure each generated function has a unique filename for profilers
- # (such as cProfile) that depend on the tuple of (<filename>,
- # <definition line>, <function name>) being unique.
- filename = '<decorator-gen-%d>' % next(self._compile_count)
- try:
- code = compile(src, filename, 'single')
- exec(code, evaldict)
- except Exception:
- print('Error in generated code:', file=sys.stderr)
- print(src, file=sys.stderr)
- raise
- func = evaldict[name]
- if addsource:
- attrs['__source__'] = src
- self.update(func, **attrs)
- return func
-
- @classmethod
- def create(cls, obj, body, evaldict, defaults=None,
- doc=None, module=None, addsource=True, **attrs):
- """
- Create a function from the strings name, signature and body.
- evaldict is the evaluation dictionary. If addsource is true an
- attribute __source__ is added to the result. The attributes attrs
- are added, if any.
- """
- if isinstance(obj, str): # "name(signature)"
- name, rest = obj.strip().split('(', 1)
- signature = rest[:-1] # strip a right parens
- func = None
- else: # a function
- name = None
- signature = None
- func = obj
- self = cls(func, name, signature, defaults, doc, module)
- ibody = '\n'.join(' ' + line for line in body.splitlines())
- caller = evaldict.get('_call_') # when called from `decorate`
- if caller and iscoroutinefunction(caller):
- body = ('async def %(name)s(%(signature)s):\n' + ibody).replace(
- 'return', 'return await')
- else:
- body = 'def %(name)s(%(signature)s):\n' + ibody
- return self.make(body, evaldict, addsource, **attrs)
-
-
-def decorate(func, caller, extras=()):
- """
- decorate(func, caller) decorates a function using a caller.
- If the caller is a generator function, the resulting function
- will be a generator function.
- """
- evaldict = dict(_call_=caller, _func_=func)
- es = ''
- for i, extra in enumerate(extras):
- ex = '_e%d_' % i
- evaldict[ex] = extra
- es += ex + ', '
-
- if '3.5' <= sys.version < '3.6':
- # with Python 3.5 isgeneratorfunction returns True for all coroutines
- # however we know that it is NOT possible to have a generator
- # coroutine in python 3.5: PEP525 was not there yet
- generatorcaller = isgeneratorfunction(
- caller) and not iscoroutinefunction(caller)
- else:
- generatorcaller = isgeneratorfunction(caller)
- if generatorcaller:
- fun = FunctionMaker.create(
- func, "for res in _call_(_func_, %s%%(shortsignature)s):\n"
- " yield res" % es, evaldict, __wrapped__=func)
- else:
- fun = FunctionMaker.create(
- func, "return _call_(_func_, %s%%(shortsignature)s)" % es,
- evaldict, __wrapped__=func)
- if hasattr(func, '__qualname__'):
- fun.__qualname__ = func.__qualname__
- return fun
-
-
-def decorator(caller, _func=None):
- """decorator(caller) converts a caller function into a decorator"""
- if _func is not None: # return a decorated function
- # this is obsolete behavior; you should use decorate instead
- return decorate(_func, caller)
- # else return a decorator function
- defaultargs, defaults = '', ()
- if inspect.isclass(caller):
- name = caller.__name__.lower()
- doc = 'decorator(%s) converts functions/generators into ' \
- 'factories of %s objects' % (caller.__name__, caller.__name__)
- elif inspect.isfunction(caller):
- if caller.__name__ == '<lambda>':
- name = '_lambda_'
- else:
- name = caller.__name__
- doc = caller.__doc__
- nargs = caller.__code__.co_argcount
- ndefs = len(caller.__defaults__ or ())
- defaultargs = ', '.join(caller.__code__.co_varnames[nargs-ndefs:nargs])
- if defaultargs:
- defaultargs += ','
- defaults = caller.__defaults__
- else: # assume caller is an object with a __call__ method
- name = caller.__class__.__name__.lower()
- doc = caller.__call__.__doc__
- evaldict = dict(_call=caller, _decorate_=decorate)
- dec = FunctionMaker.create(
- '%s(func, %s)' % (name, defaultargs),
- 'if func is None: return lambda func: _decorate_(func, _call, (%s))\n'
- 'return _decorate_(func, _call, (%s))' % (defaultargs, defaultargs),
- evaldict, doc=doc, module=caller.__module__, __wrapped__=caller)
- if defaults:
- dec.__defaults__ = (None,) + defaults
- return dec
-
-
-# ####################### contextmanager ####################### #
-
-try: # Python >= 3.2
- from contextlib import _GeneratorContextManager
-except ImportError: # Python >= 2.5
- from contextlib import GeneratorContextManager as _GeneratorContextManager
-
-
-class ContextManager(_GeneratorContextManager):
- def __call__(self, func):
- """Context manager decorator"""
- return FunctionMaker.create(
- func, "with _self_: return _func_(%(shortsignature)s)",
- dict(_self_=self, _func_=func), __wrapped__=func)
-
-
-init = getfullargspec(_GeneratorContextManager.__init__)
-n_args = len(init.args)
-if n_args == 2 and not init.varargs: # (self, genobj) Python 2.7
- def __init__(self, g, *a, **k):
- return _GeneratorContextManager.__init__(self, g(*a, **k))
- ContextManager.__init__ = __init__
-elif n_args == 2 and init.varargs: # (self, gen, *a, **k) Python 3.4
- pass
-elif n_args == 4: # (self, gen, args, kwds) Python 3.5
- def __init__(self, g, *a, **k):
- return _GeneratorContextManager.__init__(self, g, a, k)
- ContextManager.__init__ = __init__
-
-_contextmanager = decorator(ContextManager)
-
-
-def contextmanager(func):
- # Enable Pylint config: contextmanager-decorators=decorator.contextmanager
- return _contextmanager(func)
-
-
-# ############################ dispatch_on ############################ #
-
-def append(a, vancestors):
- """
- Append ``a`` to the list of the virtual ancestors, unless it is already
- included.
- """
- add = True
- for j, va in enumerate(vancestors):
- if issubclass(va, a):
- add = False
- break
- if issubclass(a, va):
- vancestors[j] = a
- add = False
- if add:
- vancestors.append(a)
-
-
-# inspired from simplegeneric by P.J. Eby and functools.singledispatch
-def dispatch_on(*dispatch_args):
- """
- Factory of decorators turning a function into a generic function
- dispatching on the given arguments.
- """
- assert dispatch_args, 'No dispatch args passed'
- dispatch_str = '(%s,)' % ', '.join(dispatch_args)
-
- def check(arguments, wrong=operator.ne, msg=''):
- """Make sure one passes the expected number of arguments"""
- if wrong(len(arguments), len(dispatch_args)):
- raise TypeError('Expected %d arguments, got %d%s' %
- (len(dispatch_args), len(arguments), msg))
-
- def gen_func_dec(func):
- """Decorator turning a function into a generic function"""
-
- # first check the dispatch arguments
- argset = set(getfullargspec(func).args)
- if not set(dispatch_args) <= argset:
- raise NameError('Unknown dispatch arguments %s' % dispatch_str)
-
- typemap = {}
-
- def vancestors(*types):
- """
- Get a list of sets of virtual ancestors for the given types
- """
- check(types)
- ras = [[] for _ in range(len(dispatch_args))]
- for types_ in typemap:
- for t, type_, ra in zip(types, types_, ras):
- if issubclass(t, type_) and type_ not in t.mro():
- append(type_, ra)
- return [set(ra) for ra in ras]
-
- def ancestors(*types):
- """
- Get a list of virtual MROs, one for each type
- """
- check(types)
- lists = []
- for t, vas in zip(types, vancestors(*types)):
- n_vas = len(vas)
- if n_vas > 1:
- raise RuntimeError(
- 'Ambiguous dispatch for %s: %s' % (t, vas))
- elif n_vas == 1:
- va, = vas
- mro = type('t', (t, va), {}).mro()[1:]
- else:
- mro = t.mro()
- lists.append(mro[:-1]) # discard t and object
- return lists
-
- def register(*types):
- """
- Decorator to register an implementation for the given types
- """
- check(types)
-
- def dec(f):
- check(getfullargspec(f).args, operator.lt, ' in ' + f.__name__)
- typemap[types] = f
- return f
- return dec
-
- def dispatch_info(*types):
- """
- An utility to introspect the dispatch algorithm
- """
- check(types)
- lst = []
- for anc in itertools.product(*ancestors(*types)):
- lst.append(tuple(a.__name__ for a in anc))
- return lst
-
- def _dispatch(dispatch_args, *args, **kw):
- types = tuple(type(arg) for arg in dispatch_args)
- try: # fast path
- f = typemap[types]
- except KeyError:
- pass
- else:
- return f(*args, **kw)
- combinations = itertools.product(*ancestors(*types))
- next(combinations) # the first one has been already tried
- for types_ in combinations:
- f = typemap.get(types_)
- if f is not None:
- return f(*args, **kw)
-
- # else call the default implementation
- return func(*args, **kw)
-
- return FunctionMaker.create(
- func, 'return _f_(%s, %%(shortsignature)s)' % dispatch_str,
- dict(_f_=_dispatch), register=register, default=func,
- typemap=typemap, vancestors=vancestors, ancestors=ancestors,
- dispatch_info=dispatch_info, __wrapped__=func)
-
- gen_func_dec.__name__ = 'dispatch_on' + dispatch_str
- return gen_func_dec
diff --git a/contrib/python/decorator/tests/__init__.py b/contrib/python/decorator/tests/__init__.py
deleted file mode 100644
index e69de29bb2..0000000000
--- a/contrib/python/decorator/tests/__init__.py
+++ /dev/null
diff --git a/contrib/python/decorator/tests/documentation.py b/contrib/python/decorator/tests/documentation.py
deleted file mode 100644
index 46a932aa77..0000000000
--- a/contrib/python/decorator/tests/documentation.py
+++ /dev/null
@@ -1,1897 +0,0 @@
-from __future__ import print_function
-import sys
-import threading
-import time
-import functools
-import itertools
-import collections
-try:
- import collections.abc as c
-except ImportError:
- c = collections
- collections.abc = collections
-from decorator import (decorator, decorate, FunctionMaker, contextmanager,
- dispatch_on, __version__)
-
-doc = r"""Decorators for Humans
-----------------------------------
-
-|Author | Michele Simionato|
-|---|---|
-|E-mail | michele.simionato@gmail.com|
-|Version| $VERSION ($DATE)|
-|Supports| Python 2.6, 2.7, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8|
-|Download page| http://pypi.python.org/pypi/decorator/$VERSION|
-|Installation| ``pip install decorator``|
-|License | BSD license|
-
-Introduction
------------------------------------------
-
-The ``decorator`` module is over ten years old, but still alive and
-kicking. It is used by several frameworks (IPython, scipy, authkit,
-pylons, pycuda, sugar, ...) and has been stable for a *long*
-time. It is your best option if you want to preserve the signature of
-decorated functions in a consistent way across Python
-releases. Version 4 is fully compatible with the past, except for
-one thing: support for Python 2.4 and 2.5 has been dropped. That
-decision made it possible to use a single code base both for Python
-2.X and Python 3.X. This is a *huge* bonus, since I could remove over
-2,000 lines of duplicated documentation/doctests. Having to maintain
-separate docs for Python 2 and Python 3 effectively stopped any
-development on the module for several years. Moreover, it is now
-trivial to distribute the module as an universal
- [wheel](http://pythonwheels.com) since 2to3 is no more
-required. Since Python 2.5 has been released ages ago (in 2006), I felt that
-it was reasonable to drop the support for it. If you need to support
-ancient versions of Python, stick with the decorator module version
-3.4.2. The current version supports all Python releases from 2.6 up.
-
-What's New in version 4
------------------------
-
-- **New documentation**
- There is now a single manual for all Python versions, so I took the
- opportunity to overhaul the documentation and to move it to readthedocs.org.
- Even if you are a long-time user, you may want to revisit the docs, since
- several examples have been improved.
-
-- **Packaging improvements**
- The code is now also available in wheel format. Integration with
- setuptools has improved and you can run the tests with the command
- ``python setup.py test`` too.
-
-- **Code changes**
- A new utility function ``decorate(func, caller)`` has been added.
- It does the same job that was performed by the older
- ``decorator(caller, func)``. The old functionality is now deprecated
- and no longer documented, but still available for now.
-
-- **Multiple dispatch**
- The decorator module now includes an implementation of generic
- functions (sometimes called "multiple dispatch functions").
- The API is designed to mimic ``functools.singledispatch`` (added
- in Python 3.4), but the implementation is much simpler.
- Moreover, all decorators involved preserve the signature of the
- decorated functions. For now, this exists mostly to demonstrate
- the power of the module. In the future it could be enhanced/optimized.
- In any case, it is very short and compact (less then 100 lines), so you
- can extract it for your own use. Take it as food for thought.
-
-- **Python 3.5 coroutines**
- From version 4.1 it is possible to decorate coroutines, i.e. functions
- defined with the `async def` syntax, and to maintain the
- `inspect.iscoroutinefunction` check working for the decorated function.
-
-- **Decorator factories**
- From version 4.2 there is facility to define factories of decorators in
- a simple way, a feature requested by the users since a long time.
-
-Usefulness of decorators
-------------------------------------------------
-
-Python decorators are an interesting example of why syntactic sugar
-matters. In principle, their introduction in Python 2.4 changed
-nothing, since they did not provide any new functionality which was not
-already present in the language. In practice, their introduction has
-significantly changed the way we structure our programs in Python. I
-believe the change is for the best, and that decorators are a great
-idea since:
-
-* decorators help reducing boilerplate code;
-* decorators help separation of concerns;
-* decorators enhance readability and maintenability;
-* decorators are explicit.
-
-Still, as of now, writing custom decorators correctly requires
-some experience and it is not as easy as it could be. For instance,
-typical implementations of decorators involve nested functions, and
-we all know that flat is better than nested.
-
-The aim of the ``decorator`` module it to simplify the usage of
-decorators for the average programmer, and to popularize decorators by
-showing various non-trivial examples. Of course, as all techniques,
-decorators can be abused (I have seen that) and you should not try to
-solve every problem with a decorator, just because you can.
-
-You may find the source code for all the examples
-discussed here in the ``documentation.py`` file, which contains
-the documentation you are reading in the form of doctests.
-
-Definitions
-------------------------------------
-
-Technically speaking, any Python object which can be called with one argument
-can be used as a decorator. However, this definition is somewhat too large
-to be really useful. It is more convenient to split the generic class of
-decorators in two subclasses:
-
-1. **signature-preserving decorators**, callable objects which accept
- a function as input and return a function as output, *with the
- same signature*
-
-2. **signature-changing** decorators, i.e. decorators
- which change the signature of their input function, or decorators
- that return non-callable objects
-
-Signature-changing decorators have their use: for instance, the
-builtin classes ``staticmethod`` and ``classmethod`` are in this
-group. They take functions and return descriptor objects which
-are neither functions, nor callables.
-
-Still, signature-preserving decorators are more common, and easier
-to reason about. In particular, they can be composed together,
-whereas other decorators generally cannot.
-
-Writing signature-preserving decorators from scratch is not that
-obvious, especially if one wants to define proper decorators that
-can accept functions with any signature. A simple example will clarify
-the issue.
-
-Statement of the problem
-------------------------------
-
-A very common use case for decorators is the memoization of functions.
-A ``memoize`` decorator works by caching
-the result of the function call in a dictionary, so that the next time
-the function is called with the same input parameters the result is retrieved
-from the cache and not recomputed.
-
-There are many implementations of ``memoize`` in
-http://www.python.org/moin/PythonDecoratorLibrary,
-but they do not preserve the signature. In recent versions of
-Python you can find a sophisticated ``lru_cache`` decorator
-in the standard library's ``functools``. Here I am just
-interested in giving an example.
-
-Consider the following simple implementation (note that it is
-generally impossible to *correctly* memoize something
-that depends on non-hashable arguments):
-
-$$memoize_uw
-
-Here I used the functools.update_wrapper_ utility, which was added
-in Python 2.5 to simplify the writing of decorators.
-(Previously, you needed to manually copy the function attributes
-``__name__``, ``__doc__``, ``__module__``, and ``__dict__``
-to the decorated function by hand).
-
-Here is an example of usage:
-
-$$f1
-
-This works insofar as the decorator accepts functions with generic signatures.
-Unfortunately, it is *not* a signature-preserving decorator, since
-``memoize_uw`` generally returns a function with a *different signature*
-from the original.
-
-Consider for instance the following case:
-
-$$f1
-
-Here, the original function takes a single argument named ``x``,
-but the decorated function takes any number of arguments and
-keyword arguments:
-
-```python
->>> from decorator import getfullargspec
->>> print(getfullargspec(f1))
-FullArgSpec(args=[], varargs='args', varkw='kw', defaults=None, kwonlyargs=[], kwonlydefaults=None, annotations={})
-
-```
-
-This means that introspection tools (like ``pydoc``) will give false
-information about the signature of ``f1`` -- unless you are using
-Python 3.5. This is pretty bad: ``pydoc`` will tell you that the
-function accepts the generic signature ``*args, **kw``, but
-calling the function with more than one argument raises an error:
-
-```python
->>> f1(0, 1) # doctest: +IGNORE_EXCEPTION_DETAIL
-Traceback (most recent call last):
- ...
-TypeError: f1() takes exactly 1 positional argument (2 given)
-
-```
-
-Notice that ``inspect.getfullargspec``
-will give the wrong signature, even in the latest Python, i.e. version 3.6
-at the time of writing.
-
-The solution
------------------------------------------
-
-The solution is to provide a generic factory of generators, which
-hides the complexity of making signature-preserving decorators
-from the application programmer. The ``decorate`` function in
-the ``decorator`` module is such a factory:
-
-```python
->>> from decorator import decorate
-
-```
-
-``decorate`` takes two arguments:
-
-1. a caller function describing the functionality of the decorator, and
-
-2. a function to be decorated.
-
-The caller function must have signature ``(f, *args, **kw)``, and it
-must call the original function ``f`` with arguments ``args`` and ``kw``,
-implementing the wanted capability (in this case, memoization):
-
-$$_memoize
-
-Now, you can define your decorator as follows:
-
-$$memoize
-
-The difference from the nested function approach of ``memoize_uw``
-is that the decorator module forces you to lift the inner function
-to the outer level. Moreover, you are forced to explicitly pass the
-function you want to decorate; there are no closures.
-
-Here is a test of usage:
-
-```python
->>> @memoize
-... def heavy_computation():
-... time.sleep(2)
-... return "done"
-
->>> print(heavy_computation()) # the first time it will take 2 seconds
-done
-
->>> print(heavy_computation()) # the second time it will be instantaneous
-done
-
-```
-
-The signature of ``heavy_computation`` is the one you would expect:
-
-```python
->>> print(getfullargspec(heavy_computation))
-FullArgSpec(args=[], varargs=None, varkw=None, defaults=None, kwonlyargs=[], kwonlydefaults=None, annotations={})
-
-```
-
-A ``trace`` decorator
-------------------------------------------------------
-
-Here is an example of how to define a simple ``trace`` decorator,
-which prints a message whenever the traced function is called:
-
-$$_trace
-
-$$trace
-
-Here is an example of usage:
-
-```python
->>> @trace
-... def f1(x):
-... pass
-
-```
-
-It is immediate to verify that ``f1`` works...
-
-```python
->>> f1(0)
-calling f1 with args (0,), {}
-
-```
-
-...and it that it has the correct signature:
-
-```python
->>> print(getfullargspec(f1))
-FullArgSpec(args=['x'], varargs=None, varkw=None, defaults=None, kwonlyargs=[], kwonlydefaults=None, annotations={})
-
-```
-
-The decorator works with functions of any signature:
-
-```python
->>> @trace
-... def f(x, y=1, z=2, *args, **kw):
-... pass
-
->>> f(0, 3)
-calling f with args (0, 3, 2), {}
-
->>> print(getfullargspec(f))
-FullArgSpec(args=['x', 'y', 'z'], varargs='args', varkw='kw', defaults=(1, 2), kwonlyargs=[], kwonlydefaults=None, annotations={})
-
-```
-$FUNCTION_ANNOTATIONS
-
-``decorator.decorator``
----------------------------------------------
-
-It can become tedious to write a caller function (like the above
-``_trace`` example) and then a trivial wrapper
-(``def trace(f): return decorate(f, _trace)``) every time.
-Not to worry! The ``decorator`` module provides an easy shortcut
-to convert the caller function into a signature-preserving decorator.
-
-It is the ``decorator`` function:
-
-```python
->>> from decorator import decorator
->>> print(decorator.__doc__)
-decorator(caller) converts a caller function into a decorator
-
-```
-The ``decorator`` function can be used as a signature-changing
-decorator, just like ``classmethod`` and ``staticmethod``.
-But ``classmethod`` and ``staticmethod`` return generic
-objects which are not callable. Instead, ``decorator`` returns
-signature-preserving decorators (i.e. functions with a single argument).
-
-For instance, you can write:
-
-```python
->>> @decorator
-... def trace(f, *args, **kw):
-... kwstr = ', '.join('%r: %r' % (k, kw[k]) for k in sorted(kw))
-... print("calling %s with args %s, {%s}" % (f.__name__, args, kwstr))
-... return f(*args, **kw)
-
-```
-
-And ``trace`` is now a decorator!
-
-```python
->>> trace # doctest: +ELLIPSIS
-<function trace at 0x...>
-
-```
-
-Here is an example of usage:
-
-```python
->>> @trace
-... def func(): pass
-
->>> func()
-calling func with args (), {}
-
-```
-
-The `decorator` function can also be used to define factories of decorators,
-i.e. functions returning decorators. In general you can just write something
-like this:
-
-```python
-def decfactory(param1, param2, ...):
- def caller(f, *args, **kw):
- return somefunc(f, param1, param2, .., *args, **kw)
- return decorator(caller)
-```
-
-This is fully general but requires an additional level of nesting. For this
-reason since version 4.2 there is a facility to build
-decorator factories by using a single caller with default arguments i.e.
-writing something like this:
-
-```python
-def caller(f, param1=default1, param2=default2, ..., *args, **kw):
- return somefunc(f, param1, param2, *args, **kw)
-decfactory = decorator(caller)
-```
-
-Notice that this simplified approach *only works with default arguments*,
-i.e. `param1`, `param2` etc must have known defaults. Thanks to this
-restriction, there exists an unique default decorator, i.e. the member
-of the family which uses the default values for all parameters. Such
-decorator can be written as ``decfactory()`` with no parameters specified;
-moreover, as a shortcut, it is also possible to elide the parenthesis,
-a feature much requested by the users. For years I have been opposite
-to this feature request, since having explicit parenthesis to me is more clear
-and less magic; however once this feature entered in decorators of
-the Python standard library (I am referring to the [dataclass decorator](
-https://www.python.org/dev/peps/pep-0557/)) I finally gave up.
-
-The example below will show how it works in practice.
-
-Decorator factories
--------------------------------------------
-
-Sometimes one has to deal with blocking resources, such as ``stdin``.
-Sometimes it is better to receive a "busy" message than just blocking
-everything.
-This can be accomplished with a suitable family of decorators (decorator
-factory), parameterize by a string, the busy message:
-
-$$blocking
-
-Functions decorated with ``blocking`` will return a busy message if
-the resource is unavailable, and the intended result if the resource is
-available. For instance:
-
-```python
->>> @blocking(msg="Please wait ...")
-... def read_data():
-... time.sleep(3) # simulate a blocking resource
-... return "some data"
-
->>> print(read_data()) # data is not available yet
-Please wait ...
-
->>> time.sleep(1)
->>> print(read_data()) # data is not available yet
-Please wait ...
-
->>> time.sleep(1)
->>> print(read_data()) # data is not available yet
-Please wait ...
-
->>> time.sleep(1.1) # after 3.1 seconds, data is available
->>> print(read_data())
-some data
-
-```
-
-Decorator factories are most useful to framework builders. Here is an example
-that gives an idea of how you could manage permissions in a framework:
-
-$$Action
-
-where ``restricted`` is a decorator factory defined as follows
-
-$$restricted
-
-Notice that if you forget to use the keyword argument notation, i.e. if you
-write ``restricted(User)`` instead of ``restricted(user_class=User)`` you
-will get an error
-
-```python
-TypeError: You are decorating a non function: <class '__main__.User'>
-
-```
-
-Be careful!
-
-``decorator(cls)``
---------------------------------------------
-
-The ``decorator`` facility can also produce a decorator starting
-from a class with the signature of a caller. In such a case the
-produced generator is able to convert functions into factories
-to create instances of that class.
-
-As an example, here is a decorator which can convert a
-blocking function into an asynchronous function. When
-the function is called, it is executed in a separate thread.
-
-(This is similar to the approach used in the ``concurrent.futures`` package.
-But I don't recommend that you implement futures this way; this is just an
-example.)
-
-$$Future
-
-The decorated function returns a ``Future`` object. It has a ``.result()``
-method which blocks until the underlying thread finishes and returns
-the final result.
-
-Here is the minimalistic usage:
-
-```python
->>> @decorator(Future)
-... def long_running(x):
-... time.sleep(.5)
-... return x
-
->>> fut1 = long_running(1)
->>> fut2 = long_running(2)
->>> fut1.result() + fut2.result()
-3
-
-```
-
-contextmanager
--------------------------------------
-
-Python's standard library has the ``contextmanager`` decorator,
-which converts a generator function into a ``GeneratorContextManager``
-factory. For instance, if you write this...
-
-```python
->>> from contextlib import contextmanager
->>> @contextmanager
-... def before_after(before, after):
-... print(before)
-... yield
-... print(after)
-
-```
-
-...then ``before_after`` is a factory function that returns
-``GeneratorContextManager`` objects, which provide the
-use of the ``with`` statement:
-
-```python
->>> with before_after('BEFORE', 'AFTER'):
-... print('hello')
-BEFORE
-hello
-AFTER
-
-```
-
-Basically, it is as if the content of the ``with`` block was executed
-in the place of the ``yield`` expression in the generator function.
-
-In Python 3.2, ``GeneratorContextManager`` objects were enhanced with
-a ``__call__`` method, so that they can be used as decorators, like so:
-
-```python
->>> ba = before_after('BEFORE', 'AFTER')
->>>
->>> @ba # doctest: +SKIP
-... def hello():
-... print('hello')
-...
->>> hello() # doctest: +SKIP
-BEFORE
-hello
-AFTER
-
-```
-
-The ``ba`` decorator basically inserts a ``with ba:`` block
-inside the function.
-
-However, there are two issues:
-
-1. ``GeneratorContextManager`` objects are only callable in Python 3.2,
- so the previous example breaks in older versions of Python.
- (You can solve this by installing ``contextlib2``, which backports
- the Python 3 functionality to Python 2.)
-
-2. ``GeneratorContextManager`` objects do not preserve the signature of
- the decorated functions. The decorated ``hello`` function above will
- have the generic signature ``hello(*args, **kwargs)``, but fails if
- called with more than zero arguments.
-
-For these reasons, the `decorator` module, starting from release 3.4, offers a
-``decorator.contextmanager`` decorator that solves both problems,
-*and* works in all supported Python versions. Its usage is identical,
-and factories decorated with ``decorator.contextmanager`` will return
-instances of ``ContextManager``, a subclass of the standard library's
-``contextlib.GeneratorContextManager`` class. The subclass includes
-an improved ``__call__`` method, which acts as a signature-preserving
-decorator.
-
-The ``FunctionMaker`` class
----------------------------------------------------------------
-
-You may wonder how the functionality of the ``decorator`` module
-is implemented. The basic building block is
-a ``FunctionMaker`` class. It generates on-the-fly functions
-with a given name and signature from a function template
-passed as a string.
-
-If you're just writing ordinary decorators, then you probably won't
-need to use ``FunctionMaker`` directly. But in some circumstances, it
-can be handy. You will see an example shortly--in
-the implementation of a cool decorator utility (``decorator_apply``).
-
-``FunctionMaker`` provides the ``.create`` classmethod, which
-accepts the *name*, *signature*, and *body* of the function
-you want to generate, as well as the execution environment
-where the function is generated by ``exec``.
-
-Here's an example:
-
-```python
->>> def f(*args, **kw): # a function with a generic signature
-... print(args, kw)
-
->>> f1 = FunctionMaker.create('f1(a, b)', 'f(a, b)', dict(f=f))
->>> f1(1,2)
-(1, 2) {}
-
-```
-
-It is important to notice that the function body is interpolated
-before being executed; **be careful** with the ``%`` sign!
-
-``FunctionMaker.create`` also accepts keyword arguments.
-The keyword arguments are attached to the generated function.
-This is useful if you want to set some function attributes
-(e.g., the docstring ``__doc__``).
-
-For debugging/introspection purposes, it may be useful to see
-the source code of the generated function. To do this, just
-pass ``addsource=True``, and the generated function will get
-a ``__source__`` attribute:
-
-```python
->>> f1 = FunctionMaker.create(
-... 'f1(a, b)', 'f(a, b)', dict(f=f), addsource=True)
->>> print(f1.__source__)
-def f1(a, b):
- f(a, b)
-<BLANKLINE>
-
-```
-
-The first argument to ``FunctionMaker.create`` can be a string (as above),
-or a function. This is the most common usage, since you typically decorate
-pre-existing functions.
-
-If you're writing a framework, however, you may want to use
-``FunctionMaker.create`` directly, rather than ``decorator``, because it gives
-you direct access to the body of the generated function.
-
-For instance, suppose you want to instrument the ``__init__`` methods of a
-set of classes, by preserving their signature.
-(This use case is not made up. This is done by SQAlchemy, and other frameworks,
-too.)
-Here is what happens:
-
-- If first argument of ``FunctionMaker.create`` is a function,
- an instance of ``FunctionMaker`` is created with the attributes
- ``args``, ``varargs``, ``keywords``, and ``defaults``.
- (These mirror the return values of the standard library's
- ``inspect.getfullargspec``.)
-
-- For each item in ``args`` (a list of strings of the names of all required
- arguments), an attribute ``arg0``, ``arg1``, ..., ``argN`` is also generated.
-
-- Finally, there is a ``signature`` attribute, which is a string with the
- signature of the original function.
-
-**NOTE:** You should not pass signature strings with default arguments
-(e.g., something like ``'f1(a, b=None)'``). Just pass ``'f1(a, b)'``,
-followed by a tuple of defaults:
-
-```python
->>> f1 = FunctionMaker.create(
-... 'f1(a, b)', 'f(a, b)', dict(f=f), addsource=True, defaults=(None,))
->>> print(getfullargspec(f1))
-FullArgSpec(args=['a', 'b'], varargs=None, varkw=None, defaults=(None,), kwonlyargs=[], kwonlydefaults=None, annotations={})
-
-```
-
-Getting the source code
----------------------------------------------------
-
-Internally, ``FunctionMaker.create`` uses ``exec`` to generate the
-decorated function. Therefore ``inspect.getsource`` will not work for
-decorated functions. In IPython, this means that the usual ``??`` trick
-will give you the (right on the spot) message ``Dynamically generated
-function. No source code available``.
-
-In the past, I considered this acceptable, since ``inspect.getsource``
-does not really work with "regular" decorators. In those cases,
-``inspect.getsource`` gives you the wrapper source code, which is probably
-not what you want:
-
-$$identity_dec
-$$example
-
-```python
->>> import inspect
->>> print(inspect.getsource(example))
- def wrapper(*args, **kw):
- return func(*args, **kw)
-<BLANKLINE>
-
-```
-
-(See bug report [1764286](http://bugs.python.org/issue1764286)
-for an explanation of what is happening).
-Unfortunately the bug still exists in all versions of Python < 3.5.
-
-However, there is a workaround. The decorated function has the ``__wrapped__``
-attribute, pointing to the original function. The simplest way to get the
-source code is to call ``inspect.getsource`` on the undecorated function:
-
-```python
->>> print(inspect.getsource(factorial.__wrapped__))
-@tail_recursive
-def factorial(n, acc=1):
- "The good old factorial"
- if n == 0:
- return acc
- return factorial(n-1, n*acc)
-<BLANKLINE>
-
-```
-
-Dealing with third-party decorators
------------------------------------------------------------------
-
-Sometimes on the net you find some cool decorator that you would
-like to include in your code. However, more often than not, the cool
-decorator is not signature-preserving. What you need is an easy way to
-upgrade third party decorators to signature-preserving decorators...
-*without* having to rewrite them in terms of ``decorator``.
-
-You can use a ``FunctionMaker`` to implement that functionality as follows:
-
-$$decorator_apply
-
-``decorator_apply`` sets the generated function's ``__wrapped__`` attribute
-to the original function, so you can get the right source code.
-If you are using a Python later than 3.2, you should also set the
-``__qualname__`` attribute to preserve the qualified name of the original
-function.
-
-Notice that I am not providing this functionality in the ``decorator``
-module directly, since I think it is best to rewrite the decorator instead
-of adding another level of indirection. However, practicality
-beats purity, so you can add ``decorator_apply`` to your toolbox and
-use it if you need to.
-
-To give a good example for ``decorator_apply``, I will show a pretty slick
-decorator that converts a tail-recursive function into an iterative function.
-I have shamelessly stolen the core concept from Kay Schluehr's recipe
-in the Python Cookbook,
-http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/496691.
-
-$$TailRecursive
-
-Here the decorator is implemented as a class returning callable
-objects.
-
-$$tail_recursive
-
-Here is how you apply the upgraded decorator to the good old factorial:
-
-$$factorial
-
-```python
->>> print(factorial(4))
-24
-
-```
-
-This decorator is pretty impressive, and should give you some food for
-thought! ;)
-
-Notice that there is no recursion limit now; you can easily compute
-``factorial(1001)`` (or larger) without filling the stack frame.
-
-Notice also that the decorator will *not* work on functions which
-are not tail recursive, such as the following:
-
-$$fact
-
-**Reminder:** A function is *tail recursive* if it does either of the
-following:
-
-- returns a value without making a recursive call; or,
-- returns directly the result of a recursive call.
-
-Python 3.5 coroutines
------------------------
-
-I am personally not using Python 3.5 coroutines yet, because at work we are
-still maintaining compatibility with Python 2.7. However, some users requested
-support for coroutines and since version 4.1 the decorator module has it.
-You should consider the support experimental and kindly report issues if
-you find any.
-
-Here I will give a single example of usage. Suppose you want to log the moment
-a coroutine starts and the moment it stops for debugging purposes. You could
-write code like the following:
-
-```python
-import time
-import logging
-from asyncio import get_event_loop, sleep, wait
-from decorator import decorator
-
- @decorator
-async def log_start_stop(coro, *args, **kwargs):
- logging.info('Starting %s%s', coro.__name__, args)
- t0 = time.time()
- await coro(*args, **kwargs)
- dt = time.time() - t0
- logging.info('Ending %s%s after %d seconds', coro.__name__, args, dt)
-
-@log_start_stop
-async def make_task(n):
- for i in range(n):
- await sleep(1)
-
-if __name__ == '__main__':
- logging.basicConfig(level=logging.INFO)
- tasks = [make_task(3), make_task(2), make_task(1)]
- get_event_loop().run_until_complete(wait(tasks))
-```
-
-and you will get an output like this:
-
-```bash
-INFO:root:Starting make_task(1,)
-INFO:root:Starting make_task(3,)
-INFO:root:Starting make_task(2,)
-INFO:root:Ending make_task(1,) after 1 seconds
-INFO:root:Ending make_task(2,) after 2 seconds
-INFO:root:Ending make_task(3,) after 3 seconds
-```
-
-This may be handy if you have trouble understanding what it going on
-with a particularly complex chain of coroutines. With a single line you
-can decorate the troubling coroutine function, understand what happens, fix the
-issue and then remove the decorator (or keep it if continuous monitoring
-of the coroutines makes sense). Notice that
-``inspect.iscoroutinefunction(make_task)``
-will return the right answer (i.e. ``True``).
-
-It is also possible to define decorators converting coroutine functions
-into regular functions, such as the following:
-
-```python
-@decorator
-def coro_to_func(coro, *args, **kw):
- "Convert a coroutine into a function"
- return get_event_loop().run_until_complete(coro(*args, **kw))
-```
-
-Notice the diffence: the caller in ``log_start_stop`` was a coroutine
-function and the associate decorator was converting coroutines->coroutines;
-the caller in ``coro_to_func`` is a regular function and converts
-coroutines -> functions.
-
-Multiple dispatch
--------------------------------------------
-
-There has been talk of implementing multiple dispatch functions
-(i.e. "generic functions") in Python for over ten years. Last year,
-something concrete was done for the first time. As of Python 3.4,
-we have the decorator ``functools.singledispatch`` to implement generic
-functions!
-
-As its name implies, it is limited to *single dispatch*; in other words,
-it is able to dispatch on the first argument of the function only.
-
-The ``decorator`` module provides the decorator factory ``dispatch_on``,
-which can be used to implement generic functions dispatching on *any* argument.
-Moreover, it can manage dispatching on more than one argument.
-(And, of course, it is signature-preserving.)
-
-Here is a concrete example (from a real-life use case) where it is desiderable
-to dispatch on the second argument.
-
-Suppose you have an ``XMLWriter`` class, which is instantiated
-with some configuration parameters, and has the ``.write`` method which
-serializes objects to XML:
-
-$$XMLWriter
-
-Here, you want to dispatch on the *second* argument; the first is already
-taken by ``self``. The ``dispatch_on`` decorator factory allows you to specify
-the dispatch argument simply by passing its name as a string. (Note
-that if you misspell the name you will get an error.)
-
-The decorated function `write` is turned into a generic function (
-`write` is a function at the idea it is decorated; it will be turned
-into a method later, at class instantiation time),
-and it is called if there are no more specialized implementations.
-
-Usually, default functions should raise a ``NotImplementedError``, thus
-forcing people to register some implementation.
-You can perform the registration with a decorator:
-
-$$writefloat
-
-Now ``XMLWriter`` can serialize floats:
-
-```python
->>> writer = XMLWriter()
->>> writer.write(2.3)
-'<float>2.3</float>'
-
-```
-
-I could give a down-to-earth example of situations in which it is desiderable
-to dispatch on more than one argument--for instance, I once implemented
-a database-access library where the first dispatching argument was the
-the database driver, and the second was the database record--but here
-I will follow tradition, and show the time-honored Rock-Paper-Scissors example:
-
-$$Rock
-$$Paper
-$$Scissors
-
-I have added an ordinal to the Rock-Paper-Scissors classes to simplify
-the implementation. The idea is to define a generic function (``win(a,
-b)``) of two arguments corresponding to the *moves* of the first and
-second players. The *moves* are instances of the classes
-Rock, Paper, and Scissors:
-
-- Paper wins over Rock
-- Scissors wins over Paper
-- Rock wins over Scissors
-
-The function will return +1 for a win, -1 for a loss, and 0 for parity.
-There are 9 combinations, but combinations with the same ordinal
-(i.e. the same class) return 0. Moreover, by exchanging the order of the
-arguments, the sign of the result changes. Therefore, it is sufficient to
-directly specify only 3 implementations:
-
-$$win
-$$winRockPaper
-$$winPaperScissors
-$$winRockScissors
-
-Here is the result:
-
-```python
->>> win(Paper(), Rock())
-1
->>> win(Scissors(), Paper())
-1
->>> win(Rock(), Scissors())
-1
->>> win(Paper(), Paper())
-0
->>> win(Rock(), Rock())
-0
->>> win(Scissors(), Scissors())
-0
->>> win(Rock(), Paper())
--1
->>> win(Paper(), Scissors())
--1
->>> win(Scissors(), Rock())
--1
-
-```
-
-The point of generic functions is that they play well with subclassing.
-For instance, suppose we define a ``StrongRock``, which does not lose against
-Paper:
-
-$$StrongRock
-$$winStrongRockPaper
-
-Then you do not need to define other implementations; they are
-inherited from the parent:
-
-```python
->>> win(StrongRock(), Scissors())
-1
-
-```
-
-You can introspect the precedence used by the dispath algorithm by
-calling ``.dispatch_info(*types)``:
-
-```python
->>> win.dispatch_info(StrongRock, Scissors)
-[('StrongRock', 'Scissors'), ('Rock', 'Scissors')]
-
-```
-
-Since there is no direct implementation for (``StrongRock``, ``Scissors``),
-the dispatcher will look at the implementation for (``Rock``, ``Scissors``)
-which is available. Internally, the algorithm is doing a cross
-product of the class precedence lists (or *Method Resolution Orders*,
-[MRO](http://www.python.org/2.3/mro.html) for short) of ``StrongRock``
- and ``Scissors``, respectively.
-
-Generic functions and virtual ancestors
--------------------------------------------------
-
-In Python, generic functions are complicated by the existence of
-"virtual ancestors": superclasses which are not in the class hierarchy.
-
-Consider this class:
-
-$$WithLength
-
-This class defines a ``__len__`` method, and is therefore
-considered to be a subclass of the abstract base class
-``collections.abc.Sized`` (``collections.Sized`` on Python 2):
-
-```python
->>> issubclass(WithLength, collections.abc.Sized)
-True
-
-```
-
-However, ``collections.abc.Sized`` is not in the MRO_ of ``WithLength``; it
-is not a true ancestor. Any implementation of generic functions (even
-with single dispatch) must go through some contorsion to take into
-account the virtual ancestors.
-
-In particular, if we define a generic function...
-
-$$get_length
-
-...implemented on all classes with a length...
-
-$$get_length_sized
-
-...then ``get_length`` must be defined on ``WithLength`` instances...
-
-```python
->>> get_length(WithLength())
-0
-
-```
-
-...even if ``collections.abc.Sized`` is not a true ancestor of ``WithLength``.
-
-Of course, this is a contrived example--you could just use the
-builtin ``len``--but you should get the idea.
-
-Since in Python it is possible to consider any instance of ``ABCMeta``
-as a virtual ancestor of any other class (it is enough to register it
-as ``ancestor.register(cls)``), any implementation of generic functions
-must be aware of the registration mechanism.
-
-For example, suppose you are using a third-party set-like class, like
-the following:
-
-$$SomeSet
-
-Here, the author of ``SomeSet`` made a mistake by inheriting from
-``collections.abc.Sized`` (instead of ``collections.abc.Set``).
-
-This is not a problem. You can register *a posteriori*
-``collections.abc.Set`` as a virtual ancestor of ``SomeSet``:
-
-```python
->>> _ = collections.abc.Set.register(SomeSet)
->>> issubclass(SomeSet, collections.abc.Set)
-True
-
-```
-
-Now, let's define an implementation of ``get_length`` specific to set:
-
-$$get_length_set
-
-The current implementation (and ``functools.singledispatch`` too)
-is able to discern that a ``Set`` is a ``Sized`` object, by looking at
-the class registry, so it uses the more specific implementation for ``Set``:
-
-```python
->>> get_length(SomeSet()) # NB: the implementation for Sized would give 0
-1
-
-```
-
-Sometimes it is not clear how to dispatch. For instance, consider a
-class ``C`` registered both as ``collections.abc.Iterable`` and
-``collections.abc.Sized``, and defines a generic function ``g`` with
-implementations for both ``collections.abc.Iterable`` *and*
-``collections.abc.Sized``:
-
-$$singledispatch_example1
-
-It is impossible to decide which implementation to use, since the ancestors
-are independent. The following function will raise a ``RuntimeError``
-when called. This is consistent with the "refuse the temptation to guess"
-philosophy. ``functools.singledispatch`` would raise a similar error.
-
-It would be easy to rely on the order of registration to decide the
-precedence order. This is reasonable, but also fragile:
-
-- if, during some refactoring, you change the registration order by mistake,
- a different implementation could be taken;
-- if implementations of the generic functions are distributed across modules,
- and you change the import order, a different implementation could be taken.
-
-So the ``decorator`` module prefers to raise an error in the face of ambiguity.
-This is the same approach taken by the standard library.
-
-However, it should be noted that the *dispatch algorithm* used by the decorator
-module is different from the one used by the standard library, so in certain
-cases you will get different answers. The difference is that
-``functools.singledispatch`` tries to insert the virtual ancestors *before* the
-base classes, whereas ``decorator.dispatch_on`` tries to insert them *after*
-the base classes.
-
-Here's an example that shows the difference:
-
-$$singledispatch_example2
-
-If you play with this example and replace the ``singledispatch`` definition
-with ``functools.singledispatch``, the assertion will break: ``g`` will return
-``"container"`` instead of ``"s"``, because ``functools.singledispatch``
-will insert the ``Container`` class right before ``S``.
-
-Notice that here I am not making any bold claim such as "the standard
-library algorithm is wrong and my algorithm is right" or viceversa. It
-just point out that there are some subtle differences. The only way to
-understand what is really happening here is to scratch your head by
-looking at the implementations. I will just notice that
-``.dispatch_info`` is quite essential to see the class precedence
-list used by algorithm:
-
-```python
->>> g, V = singledispatch_example2()
->>> g.dispatch_info(V)
-[('V',), ('Sized',), ('S',), ('Container',)]
-
-```
-
-The current implementation does not implement any kind of cooperation
-between implementations. In other words, nothing is akin either to
-call-next-method in Lisp, or to ``super`` in Python.
-
-Finally, let me notice that the decorator module implementation does
-not use any cache, whereas the ``singledispatch`` implementation does.
-
-Caveats and limitations
--------------------------------------------
-
-One thing you should be aware of, is the performance penalty of decorators.
-The worse case is shown by the following example:
-
-```bash
- $ cat performance.sh
- python3 -m timeit -s "
- from decorator import decorator
-
- @decorator
- def do_nothing(func, *args, **kw):
- return func(*args, **kw)
-
- @do_nothing
- def f():
- pass
- " "f()"
-
- python3 -m timeit -s "
- def f():
- pass
- " "f()"
-
-```
-On my laptop, using the ``do_nothing`` decorator instead of the
-plain function is five times slower:
-
-```bash
- $ bash performance.sh
- 1000000 loops, best of 3: 1.39 usec per loop
- 1000000 loops, best of 3: 0.278 usec per loop
-```
-Of course, a real life function probably does something more useful
-than the function ``f`` here, so the real life performance penalty
-*could* be negligible. As always, the only way to know if there is a
-penalty in your specific use case is to measure it.
-
-More importantly, you should be aware that decorators will make your
-tracebacks longer and more difficult to understand.
-
-Consider this example:
-
-```python
->>> @trace
-... def f():
-... 1/0
-
-```
-
-Calling ``f()`` gives you a ``ZeroDivisionError``.
-But since the function is decorated, the traceback is longer:
-
-```python
->>> f() # doctest: +ELLIPSIS
-Traceback (most recent call last):
- ...
- File "<string>", line 2, in f
- File "<doctest __main__[22]>", line 4, in trace
- return f(*args, **kw)
- File "<doctest __main__[51]>", line 3, in f
- 1/0
-ZeroDivisionError: ...
-
-```
-
-You see here the inner call to the decorator ``trace``, which calls
-``f(*args, **kw)``, and a reference to ``File "<string>", line 2, in f``.
-
-This latter reference is due to the fact that, internally, the decorator
-module uses ``exec`` to generate the decorated function. Notice that
-``exec`` is *not* responsible for the performance penalty, since is the
-called *only once* (at function decoration time); it is *not* called
-each time the decorated function is called.
-
-Presently, there is no clean way to avoid ``exec``. A clean solution
-would require changing the CPython implementation, by
-adding a hook to functions (to allow changing their signature directly).
-
-Even in Python 3.5, it is impossible to change the
-function signature directly. Thus, the ``decorator`` module is
-still useful! As a matter of fact, this is the main reason why I still
-maintain the module and release new versions.
-
-It should be noted that in Python 3.5, a *lot* of improvements have
-been made: you can decorate a function with
-``func_tools.update_wrapper``, and ``pydoc`` will see the correct
-signature. Unfortunately, the function will still have an incorrect
-signature internally, as you can see by using
-``inspect.getfullargspec``; so, all documentation tools using
-``inspect.getfullargspec`` - which has been rightly deprecated -
-will see the wrong signature.
-
-In the present implementation, decorators generated by ``decorator``
-can only be used on user-defined Python functions or methods.
-They cannot be used on generic callable objects or built-in functions,
-due to limitations of the standard library's ``inspect`` module, especially
-for Python 2. In Python 3.5, many such limitations have been removed, but
-I still think that it is cleaner and safer to decorate only functions and
-coroutines. If you want to decorate things like classmethods/staticmethods
-and general callables - which I will never support in the decorator module -
-I suggest you to look at the [wrapt](https://wrapt.readthedocs.io/en/latest/)
-project by Graeme Dumpleton.
-
-There is a strange quirk when decorating functions with keyword
-arguments, if one of the arguments has the same name used in the
-caller function for the first argument. The quirk was reported by
-David Goldstein.
-
-Here is an example where it is manifest:
-
-```python
->>> @memoize
-... def getkeys(**kw):
-... return kw.keys()
-
->>> getkeys(func='a') # doctest: +ELLIPSIS
-Traceback (most recent call last):
- ...
-TypeError: _memoize() got multiple values for ... 'func'
-
-```
-
-The error message looks really strange... until you realize that
-the caller function `_memoize` uses `func` as first argument,
-so there is a confusion between the positional argument and the
-keywork arguments.
-
-The solution is to change the name of the first argument in `_memoize`,
-or to change the implementation like so:
-
-```python
-
-def _memoize(*all_args, **kw):
- func = all_args[0]
- args = all_args[1:]
- if kw: # frozenset is used to ensure hashability
- key = args, frozenset(kw.items())
- else:
- key = args
- cache = func.cache # attribute added by memoize
- if key not in cache:
- cache[key] = func(*args, **kw)
- return cache[key]
-```
-
-This avoids the need to name the first argument, so the problem
-simply disappears. This is a technique that you should keep in mind
-when writing decorators for functions with keyword arguments. Also,
-notice that lately I have come to believe that decorating functions with
-keyword arguments is not such a good idea, and you may want not to do
-that.
-
-On a similar note, there is a restriction on argument names. For instance,
-if you name an argument ``_call_`` or ``_func_``, you will get a ``NameError``:
-
-```python
->>> @trace
-... def f(_func_): print(f)
-...
-Traceback (most recent call last):
- ...
-NameError: _func_ is overridden in
-def f(_func_):
- return _call_(_func_, _func_)
-
-```
-
-Finally, the implementation is such that the decorated function makes
-a (shallow) copy of the original function dictionary:
-
-```python
->>> def f(): pass # the original function
->>> f.attr1 = "something" # setting an attribute
->>> f.attr2 = "something else" # setting another attribute
-
->>> traced_f = trace(f) # the decorated function
-
->>> traced_f.attr1
-'something'
->>> traced_f.attr2 = "something different" # setting attr
->>> f.attr2 # the original attribute did not change
-'something else'
-
-```
-
-LICENSE (2-clause BSD)
----------------------------------------------
-
-Copyright (c) 2005-2020, Michele Simionato
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without
-modification, are permitted provided that the following conditions are
-met:
-
- Redistributions of source code must retain the above copyright
- notice, this list of conditions and the following disclaimer.
- Redistributions in bytecode form must reproduce the above copyright
- notice, this list of conditions and the following disclaimer in
- the documentation and/or other materials provided with the
- distribution.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
-INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
-BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
-OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
-ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
-TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
-USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
-DAMAGE.
-
-If you use this software and you are happy with it, consider sending me a
-note, just to gratify my ego. On the other hand, if you use this software and
-you are unhappy with it, send me a patch!
-"""
-
-function_annotations = """Function annotations
----------------------------------------------
-
-Python 3 introduced the concept of [function annotations](
-http://www.python.org/dev/peps/pep-3107/): the ability
-to annotate the signature of a function with additional information,
-stored in a dictionary named ``__annotations__``. The ``decorator`` module
-(starting from release 3.3) will understand and preserve these annotations.
-
-Here is an example:
-
-```python
->>> @trace
-... def f(x: 'the first argument', y: 'default argument'=1, z=2,
-... *args: 'varargs', **kw: 'kwargs'):
-... pass
-
-```
-
-In order to introspect functions with annotations, one needs the
-utility ``inspect.getfullargspec`` (introduced in Python 3, then
-deprecated in Python 3.5, then undeprecated in Python 3.6):
-
-```python
->>> from inspect import getfullargspec
->>> argspec = getfullargspec(f)
->>> argspec.args
-['x', 'y', 'z']
->>> argspec.varargs
-'args'
->>> argspec.varkw
-'kw'
->>> argspec.defaults
-(1, 2)
->>> argspec.kwonlyargs
-[]
->>> argspec.kwonlydefaults
-
-```
-
-You can check that the ``__annotations__`` dictionary is preserved:
-
-```python
->>> f.__annotations__ is f.__wrapped__.__annotations__
-True
-
-```
-
-Here ``f.__wrapped__`` is the original undecorated function.
-This attribute exists for consistency with the behavior of
-``functools.update_wrapper``.
-
-Another attribute copied from the original function is ``__qualname__``,
-the qualified name. This attribute was introduced in Python 3.3.
-"""
-
-if sys.version_info < (3,):
- function_annotations = ''
-
-today = time.strftime('%Y-%m-%d')
-
-__doc__ = (doc.replace('$VERSION', __version__).replace('$DATE', today)
- .replace('$FUNCTION_ANNOTATIONS', function_annotations))
-
-
-def decorator_apply(dec, func):
- """
- Decorate a function by preserving the signature even if dec
- is not a signature-preserving decorator.
- """
- return FunctionMaker.create(
- func, 'return decfunc(%(signature)s)',
- dict(decfunc=dec(func)), __wrapped__=func)
-
-
-def _trace(f, *args, **kw):
- kwstr = ', '.join('%r: %r' % (k, kw[k]) for k in sorted(kw))
- print("calling %s with args %s, {%s}" % (f.__name__, args, kwstr))
- return f(*args, **kw)
-
-
-def trace(f):
- return decorate(f, _trace)
-
-
-class Future(threading.Thread):
- """
- A class converting blocking functions into asynchronous
- functions by using threads.
- """
- def __init__(self, func, *args, **kw):
- try:
- counter = func.counter
- except AttributeError: # instantiate the counter at the first call
- counter = func.counter = itertools.count(1)
- name = '%s-%s' % (func.__name__, next(counter))
-
- def func_wrapper():
- self._result = func(*args, **kw)
- super(Future, self).__init__(target=func_wrapper, name=name)
- self.start()
-
- def result(self):
- self.join()
- return self._result
-
-
-def identity_dec(func):
- def wrapper(*args, **kw):
- return func(*args, **kw)
- return wrapper
-
-
-@identity_dec
-def example():
- pass
-
-
-def memoize_uw(func):
- func.cache = {}
-
- def memoize(*args, **kw):
- if kw: # frozenset is used to ensure hashability
- key = args, frozenset(kw.items())
- else:
- key = args
- if key not in func.cache:
- func.cache[key] = func(*args, **kw)
- return func.cache[key]
- return functools.update_wrapper(memoize, func)
-
-
-@memoize_uw
-def f1(x):
- "Simulate some long computation"
- time.sleep(1)
- return x
-
-
-def _memoize(func, *args, **kw):
- if kw: # frozenset is used to ensure hashability
- key = args, frozenset(kw.items())
- else:
- key = args
- cache = func.cache # attribute added by memoize
- if key not in cache:
- cache[key] = func(*args, **kw)
- return cache[key]
-
-
-def memoize(f):
- """
- A simple memoize implementation. It works by adding a .cache dictionary
- to the decorated function. The cache will grow indefinitely, so it is
- your responsibility to clear it, if needed.
- """
- f.cache = {}
- return decorate(f, _memoize)
-
-
-@decorator
-def blocking(f, msg='blocking', *args, **kw):
- if not hasattr(f, "thread"): # no thread running
- def set_result():
- f.result = f(*args, **kw)
- f.thread = threading.Thread(None, set_result)
- f.thread.start()
- return msg
- elif f.thread.is_alive():
- return msg
- else: # the thread is ended, return the stored result
- del f.thread
- return f.result
-
-
-class User(object):
- "Will just be able to see a page"
-
-
-class PowerUser(User):
- "Will be able to add new pages too"
-
-
-class Admin(PowerUser):
- "Will be able to delete pages too"
-
-
-class PermissionError(Exception):
- """
- >>> a = Action()
- >>> a.user = User()
- >>> a.view() # ok
- >>> a.insert() # doctest: +IGNORE_EXCEPTION_DETAIL
- Traceback (most recent call last):
- ...
- PermissionError: User does not have the permission to run insert!
- """
-
-
-@decorator
-def restricted(func, user_class=User, *args, **kw):
- "Restrict access to a given class of users"
- self = args[0]
- if isinstance(self.user, user_class):
- return func(*args, **kw)
- else:
- raise PermissionError(
- '%s does not have the permission to run %s!'
- % (self.user, func.__name__))
-
-
-class Action(object):
- @restricted(user_class=User)
- def view(self):
- "Any user can view objects"
-
- @restricted(user_class=PowerUser)
- def insert(self):
- "Only power users can insert objects"
-
- @restricted(user_class=Admin)
- def delete(self):
- "Only the admin can delete objects"
-
-
-class TailRecursive(object):
- """
- tail_recursive decorator based on Kay Schluehr's recipe
- http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/496691
- with improvements by me and George Sakkis.
- """
-
- def __init__(self, func):
- self.func = func
- self.firstcall = True
- self.CONTINUE = object() # sentinel
-
- def __call__(self, *args, **kwd):
- CONTINUE = self.CONTINUE
- if self.firstcall:
- func = self.func
- self.firstcall = False
- try:
- while True:
- result = func(*args, **kwd)
- if result is CONTINUE: # update arguments
- args, kwd = self.argskwd
- else: # last call
- return result
- finally:
- self.firstcall = True
- else: # return the arguments of the tail call
- self.argskwd = args, kwd
- return CONTINUE
-
-
-def tail_recursive(func):
- return decorator_apply(TailRecursive, func)
-
-
-@tail_recursive
-def factorial(n, acc=1):
- "The good old factorial"
- if n == 0:
- return acc
- return factorial(n-1, n*acc)
-
-
-def fact(n): # this is not tail-recursive
- if n == 0:
- return 1
- return n * fact(n-1)
-
-
-def a_test_for_pylons():
- """
- In version 3.1.0 decorator(caller) returned a nameless partial
- object, thus breaking Pylons. That must not happen again.
-
- >>> decorator(_memoize).__name__
- '_memoize'
-
- Here is another bug of version 3.1.1 missing the docstring:
-
- >>> factorial.__doc__
- 'The good old factorial'
- """
-
-
-if sys.version_info >= (3,): # tests for signatures specific to Python 3
-
- def test_kwonlydefaults():
- """
- >>> @trace
- ... def f(arg, defarg=1, *args, kwonly=2): pass
- ...
- >>> f.__kwdefaults__
- {'kwonly': 2}
- """
-
- def test_kwonlyargs():
- """
- >>> @trace
- ... def func(a, b, *args, y=2, z=3, **kwargs):
- ... return y, z
- ...
- >>> func('a', 'b', 'c', 'd', 'e', y='y', z='z', cat='dog')
- calling func with args ('a', 'b', 'c', 'd', 'e'), {'cat': 'dog', 'y': 'y', 'z': 'z'}
- ('y', 'z')
- """
-
- def test_kwonly_no_args():
- """# this was broken with decorator 3.3.3
- >>> @trace
- ... def f(**kw): pass
- ...
- >>> f()
- calling f with args (), {}
- """
-
- def test_kwonly_star_notation():
- """
- >>> @trace
- ... def f(*, a=1, **kw): pass
- ...
- >>> import inspect
- >>> inspect.getfullargspec(f)
- FullArgSpec(args=[], varargs=None, varkw='kw', defaults=None, kwonlyargs=['a'], kwonlydefaults={'a': 1}, annotations={})
- """
-
-
-@contextmanager
-def before_after(before, after):
- print(before)
- yield
- print(after)
-
-
-ba = before_after('BEFORE', 'AFTER') # ContextManager instance
-
-
-@ba
-def hello(user):
- """
- >>> ba.__class__.__name__
- 'ContextManager'
- >>> hello('michele')
- BEFORE
- hello michele
- AFTER
- """
- print('hello %s' % user)
-
-
-# ####################### multiple dispatch ############################ #
-
-
-class XMLWriter(object):
- def __init__(self, **config):
- self.cfg = config
-
- @dispatch_on('obj')
- def write(self, obj):
- raise NotImplementedError(type(obj))
-
-
-@XMLWriter.write.register(float)
-def writefloat(self, obj):
- return '<float>%s</float>' % obj
-
-
-class Rock(object):
- ordinal = 0
-
-
-class Paper(object):
- ordinal = 1
-
-
-class Scissors(object):
- ordinal = 2
-
-
-class StrongRock(Rock):
- pass
-
-
-@dispatch_on('a', 'b')
-def win(a, b):
- if a.ordinal == b.ordinal:
- return 0
- elif a.ordinal > b.ordinal:
- return -win(b, a)
- raise NotImplementedError((type(a), type(b)))
-
-
-@win.register(Rock, Paper)
-def winRockPaper(a, b):
- return -1
-
-
-@win.register(Rock, Scissors)
-def winRockScissors(a, b):
- return 1
-
-
-@win.register(Paper, Scissors)
-def winPaperScissors(a, b):
- return -1
-
-
-@win.register(StrongRock, Paper)
-def winStrongRockPaper(a, b):
- return 0
-
-
-class WithLength(object):
- def __len__(self):
- return 0
-
-
-class SomeSet(collections.abc.Sized):
- # methods that make SomeSet set-like
- # not shown ...
- def __len__(self):
- return 0
-
-
-@dispatch_on('obj')
-def get_length(obj):
- raise NotImplementedError(type(obj))
-
-
-@get_length.register(collections.abc.Sized)
-def get_length_sized(obj):
- return len(obj)
-
-
-@get_length.register(collections.abc.Set)
-def get_length_set(obj):
- return 1
-
-
-class C(object):
- "Registered as Sized and Iterable"
-
-
-collections.abc.Sized.register(C)
-collections.abc.Iterable.register(C)
-
-
-def singledispatch_example1():
- singledispatch = dispatch_on('obj')
-
- @singledispatch
- def g(obj):
- raise NotImplementedError(type(g))
-
- @g.register(collections.abc.Sized)
- def g_sized(object):
- return "sized"
-
- @g.register(collections.abc.Iterable)
- def g_iterable(object):
- return "iterable"
-
- g(C()) # RuntimeError: Ambiguous dispatch: Iterable or Sized?
-
-
-def singledispatch_example2():
- # adapted from functools.singledispatch test case
- singledispatch = dispatch_on('arg')
-
- class S(object):
- pass
-
- class V(c.Sized, S):
- def __len__(self):
- return 0
-
- @singledispatch
- def g(arg):
- return "base"
-
- @g.register(S)
- def g_s(arg):
- return "s"
-
- @g.register(c.Container)
- def g_container(arg):
- return "container"
-
- v = V()
- assert g(v) == "s"
- c.Container.register(V) # add c.Container to the virtual mro of V
- assert g(v) == "s" # since the virtual mro is V, Sized, S, Container
- return g, V
-
-
-@decorator
-def warn_slow(func, duration=0, *args, **kwargs):
- t0 = time.time()
- res = func(*args, **kwargs)
- dt = time.time() - t0
- if dt >= duration:
- print('%s is slow' % func.__name__)
- return res
-
-
-@warn_slow() # with parens
-def operation1():
- """
- >>> operation1()
- operation1 is slow
- """
- time.sleep(.1)
-
-
-@warn_slow # without parens
-def operation2():
- """
- >>> operation2()
- operation2 is slow
- """
- time.sleep(.1)
-
-
-if __name__ == '__main__':
- import doctest
- doctest.testmod()
diff --git a/contrib/python/decorator/tests/test.py b/contrib/python/decorator/tests/test.py
deleted file mode 100644
index 7ddfaf45b9..0000000000
--- a/contrib/python/decorator/tests/test.py
+++ /dev/null
@@ -1,480 +0,0 @@
-from __future__ import absolute_import
-import sys
-import doctest
-import unittest
-import decimal
-import inspect
-import functools
-import collections
-from collections import defaultdict
-try:
- c = collections.abc
-except AttributeError:
- c = collections
-from decorator import dispatch_on, contextmanager, decorator
-try:
- from . import documentation as doc
-except (ImportError, ValueError, SystemError): # depending on the py-version
- import documentation as doc
-
-
-@contextmanager
-def assertRaises(etype):
- """This works in Python 2.6 too"""
- try:
- yield
- except etype:
- pass
- else:
- raise Exception('Expected %s' % etype.__name__)
-
-
-if sys.version_info >= (3, 5):
- exec('''from asyncio import get_event_loop
-
-@decorator
-async def before_after(coro, *args, **kwargs):
- return "<before>" + (await coro(*args, **kwargs)) + "<after>"
-
-@decorator
-def coro_to_func(coro, *args, **kw):
- return get_event_loop().run_until_complete(coro(*args, **kw))
-
-class CoroutineTestCase(unittest.TestCase):
- def test_before_after(self):
- @before_after
- async def coro(x):
- return x
- self.assertTrue(inspect.iscoroutinefunction(coro))
- out = get_event_loop().run_until_complete(coro('x'))
- self.assertEqual(out, '<before>x<after>')
-
- def test_coro_to_func(self):
- @coro_to_func
- async def coro(x):
- return x
- self.assertFalse(inspect.iscoroutinefunction(coro))
- self.assertEqual(coro('x'), 'x')
-''')
-
-
-def gen123():
- yield 1
- yield 2
- yield 3
-
-
-class GeneratorCallerTestCase(unittest.TestCase):
- def test_gen123(self):
- @decorator
- def square(func, *args, **kw):
- for x in gen123():
- yield x * x
- new = square(gen123)
- self.assertTrue(inspect.isgeneratorfunction(new))
- self.assertEqual(list(new()), [1, 4, 9])
-
-
-class DocumentationTestCase(unittest.TestCase):
- def test(self):
- err = doctest.testmod(doc)[0]
- self.assertEqual(err, 0)
-
- def test_singledispatch1(self):
- if hasattr(functools, 'singledispatch'):
- with assertRaises(RuntimeError):
- doc.singledispatch_example1()
-
- def test_singledispatch2(self):
- if hasattr(functools, 'singledispatch'):
- doc.singledispatch_example2()
-
-
-class ExtraTestCase(unittest.TestCase):
- def test_qualname(self):
- if sys.version_info >= (3, 3):
- self.assertEqual(doc.hello.__qualname__, 'hello')
- else:
- with assertRaises(AttributeError):
- doc.hello.__qualname__
-
- def test_signature(self):
- if hasattr(inspect, 'signature'):
- sig = inspect.signature(doc.f1)
- self.assertEqual(str(sig), '(x)')
-
- def test_unique_filenames(self):
- @decorator
- def d1(f, *args, **kwargs):
- return f(*args, **kwargs)
-
- @decorator
- def d2(f, *args, **kwargs):
- return f(*args, **kwargs)
-
- @d1
- def f1(x, y, z):
- pass
-
- @d2
- def f2(x, y, z):
- pass
-
- f1_orig = f1
-
- @d1
- def f1(x, y, z):
- pass
- self.assertNotEqual(d1.__code__.co_filename, d2.__code__.co_filename)
- self.assertNotEqual(f1.__code__.co_filename, f2.__code__.co_filename)
- self.assertNotEqual(f1_orig.__code__.co_filename,
- f1.__code__.co_filename)
-
- def test_no_first_arg(self):
- @decorator
- def example(*args, **kw):
- return args[0](*args[1:], **kw)
-
- @example
- def func(**kw):
- return kw
-
- # there is no confusion when passing args as a keyword argument
- self.assertEqual(func(args='a'), {'args': 'a'})
-
- def test_decorator_factory(self):
- # similar to what IPython is doing in traitlets.config.application
- @decorator
- def catch_config_error(method, app, *args, **kwargs):
- return method(app)
- catch_config_error(lambda app: None)
-
- def test_add1(self):
- # similar to what IPython is doing in traitlets.config.application
- @decorator
- def add(func, const=1, *args, **kwargs):
- return const + func(*args, **kwargs)
-
- def f(x):
- return x
- self.assertEqual(add(f, 2)(0), 2)
-
-
-# ################### test dispatch_on ############################# #
-# adapted from test_functools in Python 3.5
-singledispatch = dispatch_on('obj')
-
-
-class TestSingleDispatch(unittest.TestCase):
- def test_simple_overloads(self):
- @singledispatch
- def g(obj):
- return "base"
-
- @g.register(int)
- def g_int(i):
- return "integer"
-
- self.assertEqual(g("str"), "base")
- self.assertEqual(g(1), "integer")
- self.assertEqual(g([1, 2, 3]), "base")
-
- def test_mro(self):
- @singledispatch
- def g(obj):
- return "base"
-
- class A(object):
- pass
-
- class C(A):
- pass
-
- class B(A):
- pass
-
- class D(C, B):
- pass
-
- @g.register(A)
- def g_A(a):
- return "A"
-
- @g.register(B)
- def g_B(b):
- return "B"
-
- self.assertEqual(g(A()), "A")
- self.assertEqual(g(B()), "B")
- self.assertEqual(g(C()), "A")
- self.assertEqual(g(D()), "B")
-
- def test_register_decorator(self):
- @singledispatch
- def g(obj):
- return "base"
-
- @g.register(int)
- def g_int(i):
- return "int %s" % (i,)
- self.assertEqual(g(""), "base")
- self.assertEqual(g(12), "int 12")
-
- def test_register_error(self):
- @singledispatch
- def g(obj):
- return "base"
-
- with assertRaises(TypeError):
- # wrong number of arguments
- @g.register(int)
- def g_int():
- return "int"
-
- def test_wrapping_attributes(self):
- @singledispatch
- def g(obj):
- "Simple test"
- return "Test"
- self.assertEqual(g.__name__, "g")
- if sys.flags.optimize < 2:
- self.assertEqual(g.__doc__, "Simple test")
-
- def test_c_classes(self):
- @singledispatch
- def g(obj):
- return "base"
-
- @g.register(decimal.DecimalException)
- def _(obj):
- return obj.args
- subn = decimal.Subnormal("Exponent < Emin")
- rnd = decimal.Rounded("Number got rounded")
- self.assertEqual(g(subn), ("Exponent < Emin",))
- self.assertEqual(g(rnd), ("Number got rounded",))
-
- @g.register(decimal.Subnormal)
- def _g(obj):
- return "Too small to care."
- self.assertEqual(g(subn), "Too small to care.")
- self.assertEqual(g(rnd), ("Number got rounded",))
-
- def test_register_abc(self):
- d = {"a": "b"}
- l = [1, 2, 3]
- s = set([object(), None])
- f = frozenset(s)
- t = (1, 2, 3)
-
- @singledispatch
- def g(obj):
- return "base"
-
- self.assertEqual(g(d), "base")
- self.assertEqual(g(l), "base")
- self.assertEqual(g(s), "base")
- self.assertEqual(g(f), "base")
- self.assertEqual(g(t), "base")
-
- g.register(c.Sized)(lambda obj: "sized")
- self.assertEqual(g(d), "sized")
- self.assertEqual(g(l), "sized")
- self.assertEqual(g(s), "sized")
- self.assertEqual(g(f), "sized")
- self.assertEqual(g(t), "sized")
-
- g.register(c.MutableMapping)(lambda obj: "mutablemapping")
- self.assertEqual(g(d), "mutablemapping")
- self.assertEqual(g(l), "sized")
- self.assertEqual(g(s), "sized")
- self.assertEqual(g(f), "sized")
- self.assertEqual(g(t), "sized")
-
- if hasattr(c, 'ChainMap'):
- g.register(c.ChainMap)(lambda obj: "chainmap")
- # irrelevant ABCs registered
- self.assertEqual(g(d), "mutablemapping")
- self.assertEqual(g(l), "sized")
- self.assertEqual(g(s), "sized")
- self.assertEqual(g(f), "sized")
- self.assertEqual(g(t), "sized")
-
- g.register(c.MutableSequence)(lambda obj: "mutablesequence")
- self.assertEqual(g(d), "mutablemapping")
- self.assertEqual(g(l), "mutablesequence")
- self.assertEqual(g(s), "sized")
- self.assertEqual(g(f), "sized")
- self.assertEqual(g(t), "sized")
-
- g.register(c.MutableSet)(lambda obj: "mutableset")
- self.assertEqual(g(d), "mutablemapping")
- self.assertEqual(g(l), "mutablesequence")
- self.assertEqual(g(s), "mutableset")
- self.assertEqual(g(f), "sized")
- self.assertEqual(g(t), "sized")
-
- g.register(c.Mapping)(lambda obj: "mapping")
- self.assertEqual(g(d), "mutablemapping") # not specific enough
- self.assertEqual(g(l), "mutablesequence")
- self.assertEqual(g(s), "mutableset")
- self.assertEqual(g(f), "sized")
- self.assertEqual(g(t), "sized")
-
- g.register(c.Sequence)(lambda obj: "sequence")
- self.assertEqual(g(d), "mutablemapping")
- self.assertEqual(g(l), "mutablesequence")
- self.assertEqual(g(s), "mutableset")
- self.assertEqual(g(f), "sized")
- self.assertEqual(g(t), "sequence")
-
- g.register(c.Set)(lambda obj: "set")
- self.assertEqual(g(d), "mutablemapping")
- self.assertEqual(g(l), "mutablesequence")
- self.assertEqual(g(s), "mutableset")
- self.assertEqual(g(f), "set")
- self.assertEqual(g(t), "sequence")
-
- g.register(dict)(lambda obj: "dict")
- self.assertEqual(g(d), "dict")
- self.assertEqual(g(l), "mutablesequence")
- self.assertEqual(g(s), "mutableset")
- self.assertEqual(g(f), "set")
- self.assertEqual(g(t), "sequence")
-
- g.register(list)(lambda obj: "list")
- self.assertEqual(g(d), "dict")
- self.assertEqual(g(l), "list")
- self.assertEqual(g(s), "mutableset")
- self.assertEqual(g(f), "set")
- self.assertEqual(g(t), "sequence")
-
- g.register(set)(lambda obj: "concrete-set")
- self.assertEqual(g(d), "dict")
- self.assertEqual(g(l), "list")
- self.assertEqual(g(s), "concrete-set")
- self.assertEqual(g(f), "set")
- self.assertEqual(g(t), "sequence")
-
- g.register(frozenset)(lambda obj: "frozen-set")
- self.assertEqual(g(d), "dict")
- self.assertEqual(g(l), "list")
- self.assertEqual(g(s), "concrete-set")
- self.assertEqual(g(f), "frozen-set")
- self.assertEqual(g(t), "sequence")
-
- g.register(tuple)(lambda obj: "tuple")
- self.assertEqual(g(d), "dict")
- self.assertEqual(g(l), "list")
- self.assertEqual(g(s), "concrete-set")
- self.assertEqual(g(f), "frozen-set")
- self.assertEqual(g(t), "tuple")
-
- def test_mro_conflicts(self):
- @singledispatch
- def g(obj):
- return "base"
-
- class O(c.Sized):
- def __len__(self):
- return 0
- o = O()
- self.assertEqual(g(o), "base")
- g.register(c.Iterable)(lambda arg: "iterable")
- g.register(c.Container)(lambda arg: "container")
- g.register(c.Sized)(lambda arg: "sized")
- g.register(c.Set)(lambda arg: "set")
- self.assertEqual(g(o), "sized")
- c.Iterable.register(O)
- self.assertEqual(g(o), "sized")
- c.Container.register(O)
- with assertRaises(RuntimeError): # was "sized" because in mro
- self.assertEqual(g(o), "sized")
- c.Set.register(O)
- self.assertEqual(g(o), "set")
-
- class P(object):
- pass
- p = P()
- self.assertEqual(g(p), "base")
- c.Iterable.register(P)
- self.assertEqual(g(p), "iterable")
- c.Container.register(P)
-
- with assertRaises(RuntimeError):
- self.assertEqual(g(p), "iterable")
-
- class Q(c.Sized):
- def __len__(self):
- return 0
- q = Q()
- self.assertEqual(g(q), "sized")
- c.Iterable.register(Q)
- self.assertEqual(g(q), "sized")
- c.Set.register(Q)
- self.assertEqual(g(q), "set")
- # because c.Set is a subclass of c.Sized and c.Iterable
-
- @singledispatch
- def h(obj):
- return "base"
-
- @h.register(c.Sized)
- def h_sized(arg):
- return "sized"
-
- @h.register(c.Container)
- def h_container(arg):
- return "container"
- # Even though Sized and Container are explicit bases of MutableMapping,
- # this ABC is implicitly registered on defaultdict which makes all of
- # MutableMapping's bases implicit as well from defaultdict's
- # perspective.
- with assertRaises(RuntimeError):
- self.assertEqual(h(defaultdict(lambda: 0)), "sized")
-
- class R(defaultdict):
- pass
- c.MutableSequence.register(R)
-
- @singledispatch
- def i(obj):
- return "base"
-
- @i.register(c.MutableMapping)
- def i_mapping(arg):
- return "mapping"
-
- @i.register(c.MutableSequence)
- def i_sequence(arg):
- return "sequence"
- r = R()
- with assertRaises(RuntimeError): # was no error
- self.assertEqual(i(r), "sequence")
-
- class S(object):
- pass
-
- class T(S, c.Sized):
- def __len__(self):
- return 0
- t = T()
- self.assertEqual(h(t), "sized")
- c.Container.register(T)
- self.assertEqual(h(t), "sized") # because it's explicitly in the MRO
-
- class U(object):
- def __len__(self):
- return 0
- u = U()
- self.assertEqual(h(u), "sized")
- # implicit Sized subclass inferred
- # from the existence of __len__()
-
- c.Container.register(U)
- # There is no preference for registered versus inferred ABCs.
- with assertRaises(RuntimeError):
- h(u)
-
-
-if __name__ == '__main__':
- unittest.main()