# The MIT License

#

# Copyright (c) 2009-2010 the bpython authors.

#

# Permission is hereby granted, free of charge, to any person obtaining a copy

# of this software and associated documentation files (the "Software"), to deal

# in the Software without restriction, including without limitation the rights

# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

# copies of the Software, and to permit persons to whom the Software is

# furnished to do so, subject to the following conditions:

#

# The above copyright notice and this permission notice shall be included in

# all copies or substantial portions of the Software.

#

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

# THE SOFTWARE.

#

from __future__ import with_statement

import collections

import inspect

import pydoc

import re

import sys

import types

from pygments.lexers import PythonLexer

from pygments.token import Token

try:

collections.Callable

has_collections_callable = True

try:

import types

types.InstanceType

has_instance_type = True

except AttributeError:

has_instance_type = False

except AttributeError:

has_collections_callable = False

py3 = sys.version_info[0] == 3

if not py3:

_name = re.compile(r'[a-zA-Z_]\w*')

class AttrCleaner(object):

"""A context manager that tries to make an object not exhibit side-effects

on attribute lookup."""

def __init__(self, obj):

self.obj = obj

def __enter__(self):

"""Try to make an object not exhibit side-effects on attribute

lookup."""

type_ = type(self.obj)

__getattribute__ = None

__getattr__ = None

# Dark magic:

# If __getattribute__ doesn't exist on the class and __getattr__ does

# then __getattr__ will be called when doing

# getattr(type_, '__getattribute__', None)

# so we need to first remove the __getattr__, then the

# __getattribute__, then look up the attributes and then restore the

# original methods. :-(

# The upshot being that introspecting on an object to display its

# attributes will avoid unwanted side-effects.

if py3 or type_ != types.InstanceType:

__getattr__ = getattr(type_, '__getattr__', None)

if __getattr__ is not None:

try:

setattr(type_, '__getattr__', (lambda *_, **__: None))

except TypeError:

__getattr__ = None

__getattribute__ = getattr(type_, '__getattribute__', None)

if __getattribute__ is not None:

try:

setattr(type_, '__getattribute__', object.__getattribute__)

except TypeError:

# XXX: This happens for e.g. built-in types

__getattribute__ = None

self.attribs = (__getattribute__, __getattr__)

# /Dark magic

def __exit__(self, exc_type, exc_val, exc_tb):

"""Restore an object's magic methods."""

type_ = type(self.obj)

__getattribute__, __getattr__ = self.attribs

# Dark magic:

if __getattribute__ is not None:

setattr(type_, '__getattribute__', __getattribute__)

if __getattr__ is not None:

setattr(type_, '__getattr__', __getattr__)

# /Dark magic

def parsekeywordpairs(signature):

tokens = PythonLexer().get_tokens(signature)

stack = []

substack = []

parendepth = 0

begin = False

for token, value in tokens:

if not begin:

if token is Token.Punctuation and value == u'(':

begin = True

continue

if token is Token.Punctuation:

if value == u'(':

parendepth += 1

elif value == u')':

parendepth -= 1

elif value == ':' and parendepth == -1:

# End of signature reached

break

if parendepth > 0:

substack.append(value)

continue

if (token is Token.Punctuation and

(value == ',' or (value == ')' and parendepth == -1))):

stack.append(substack[:])

del substack[:]

continue

if value and value.strip():

substack.append(value)

d = {}

for item in stack:

if len(item) >= 3:

d[item[0]] = ''.join(item[2:])

return d

def fixlongargs(f, argspec):

"""Functions taking default arguments that are references to other objects

whose str() is too big will cause breakage, so we swap out the object

itself with the name it was referenced with in the source by parsing the

source itself !"""

if argspec[3] is None:

# No keyword args, no need to do anything

return

values = list(argspec[3])

if not values:

return

keys = argspec[0][-len(values):]

try:

src = inspect.getsourcelines(f)

except IOError:

return

signature = ''.join(src[0])

kwparsed = parsekeywordpairs(signature)

for i, (key, value) in enumerate(zip(keys, values)):

if len(str(value)) != len(kwparsed[key]):

values[i] = kwparsed[key]

argspec[3] = values

def getpydocspec(f, func):

try:

argspec = pydoc.getdoc(f)

except NameError:

return None

rx = re.compile(r'([a-zA-Z_][a-zA-Z0-9_]*?)\((.*?)\)')

s = rx.search(argspec)

if s is None:

return None

if not hasattr(f, '__name__') or s.groups()[0] != f.__name__:

return None

args = list()

defaults = list()

varargs = varkwargs = None

kwonly_args = list()

kwonly_defaults = dict()

for arg in s.group(2).split(','):

arg = arg.strip()

if arg.startswith('**'):

varkwargs = arg[2:]

elif arg.startswith('*'):

varargs = arg[1:]

else:

arg, _, default = arg.partition('=')

if varargs is not None:

kwonly_args.append(arg)

if default:

kwonly_defaults[arg] = default

else:

args.append(arg)

if default:

defaults.append(default)

return [func, (args, varargs, varkwargs, defaults,

kwonly_args, kwonly_defaults)]

def getargspec(func, f):

is_bound_method = inspect.ismethod(f) and f.im_self is not None

try:

if py3:

argspec = inspect.getfullargspec(f)

else:

argspec = inspect.getargspec(f)

argspec = list(argspec)

fixlongargs(f, argspec)

argspec = [func, argspec, is_bound_method]

except (TypeError, KeyError):

with AttrCleaner(f):

argspec = getpydocspec(f, func)

if argspec is None:

return None

if inspect.ismethoddescriptor(f):

argspec[1][0].insert(0, 'obj')

argspec.append(is_bound_method)

return argspec

def is_eval_safe_name(string):

if py3:

return all(part.isidentifier() for part in string.split('.'))

else:

return all(_name.match(part) for part in string.split('.'))

def is_callable(obj):

if has_instance_type and isinstance(obj, types.InstanceType):

# Work around a Python bug, see issue 7624

return callable(obj)

elif has_collections_callable:

return isinstance(obj, collections.Callable)

else:

return callable(obj)