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Diffstat (limited to 'lib/python2.7/site-packages/zope.interface-3.6.4-py2.7-linux-x86_64.egg/zope/interface/advice.py')
| -rw-r--r-- | lib/python2.7/site-packages/zope.interface-3.6.4-py2.7-linux-x86_64.egg/zope/interface/advice.py | 201 |
1 files changed, 0 insertions, 201 deletions
diff --git a/lib/python2.7/site-packages/zope.interface-3.6.4-py2.7-linux-x86_64.egg/zope/interface/advice.py b/lib/python2.7/site-packages/zope.interface-3.6.4-py2.7-linux-x86_64.egg/zope/interface/advice.py deleted file mode 100644 index d23818ee..00000000 --- a/lib/python2.7/site-packages/zope.interface-3.6.4-py2.7-linux-x86_64.egg/zope/interface/advice.py +++ /dev/null @@ -1,201 +0,0 @@ -############################################################################## -# -# Copyright (c) 2003 Zope Foundation and Contributors. -# All Rights Reserved. -# -# This software is subject to the provisions of the Zope Public License, -# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution. -# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED -# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED -# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS -# FOR A PARTICULAR PURPOSE. -# -############################################################################## -"""Class advice. - -This module was adapted from 'protocols.advice', part of the Python -Enterprise Application Kit (PEAK). Please notify the PEAK authors -(pje@telecommunity.com and tsarna@sarna.org) if bugs are found or -Zope-specific changes are required, so that the PEAK version of this module -can be kept in sync. - -PEAK is a Python application framework that interoperates with (but does -not require) Zope 3 and Twisted. It provides tools for manipulating UML -models, object-relational persistence, aspect-oriented programming, and more. -Visit the PEAK home page at http://peak.telecommunity.com for more information. -""" - -from types import FunctionType -try: - from types import ClassType - __python3 = False -except ImportError: - __python3 = True - -import sys - -def getFrameInfo(frame): - """Return (kind,module,locals,globals) for a frame - - 'kind' is one of "exec", "module", "class", "function call", or "unknown". - """ - - f_locals = frame.f_locals - f_globals = frame.f_globals - - sameNamespace = f_locals is f_globals - hasModule = '__module__' in f_locals - hasName = '__name__' in f_globals - - sameName = hasModule and hasName - sameName = sameName and f_globals['__name__']==f_locals['__module__'] - - module = hasName and sys.modules.get(f_globals['__name__']) or None - - namespaceIsModule = module and module.__dict__ is f_globals - - if not namespaceIsModule: - # some kind of funky exec - kind = "exec" - elif sameNamespace and not hasModule: - kind = "module" - elif sameName and not sameNamespace: - kind = "class" - elif not sameNamespace: - kind = "function call" - else: - # How can you have f_locals is f_globals, and have '__module__' set? - # This is probably module-level code, but with a '__module__' variable. - kind = "unknown" - return kind, module, f_locals, f_globals - - -def addClassAdvisor(callback, depth=2): - """Set up 'callback' to be passed the containing class upon creation - - This function is designed to be called by an "advising" function executed - in a class suite. The "advising" function supplies a callback that it - wishes to have executed when the containing class is created. The - callback will be given one argument: the newly created containing class. - The return value of the callback will be used in place of the class, so - the callback should return the input if it does not wish to replace the - class. - - The optional 'depth' argument to this function determines the number of - frames between this function and the targeted class suite. 'depth' - defaults to 2, since this skips this function's frame and one calling - function frame. If you use this function from a function called directly - in the class suite, the default will be correct, otherwise you will need - to determine the correct depth yourself. - - This function works by installing a special class factory function in - place of the '__metaclass__' of the containing class. Therefore, only - callbacks *after* the last '__metaclass__' assignment in the containing - class will be executed. Be sure that classes using "advising" functions - declare any '__metaclass__' *first*, to ensure all callbacks are run.""" - - frame = sys._getframe(depth) - kind, module, caller_locals, caller_globals = getFrameInfo(frame) - - # This causes a problem when zope interfaces are used from doctest. - # In these cases, kind == "exec". - # - #if kind != "class": - # raise SyntaxError( - # "Advice must be in the body of a class statement" - # ) - - previousMetaclass = caller_locals.get('__metaclass__') - if __python3: - defaultMetaclass = caller_globals.get('__metaclass__', type) - else: - defaultMetaclass = caller_globals.get('__metaclass__', ClassType) - - - def advise(name, bases, cdict): - - if '__metaclass__' in cdict: - del cdict['__metaclass__'] - - if previousMetaclass is None: - if bases: - # find best metaclass or use global __metaclass__ if no bases - meta = determineMetaclass(bases) - else: - meta = defaultMetaclass - - elif isClassAdvisor(previousMetaclass): - # special case: we can't compute the "true" metaclass here, - # so we need to invoke the previous metaclass and let it - # figure it out for us (and apply its own advice in the process) - meta = previousMetaclass - - else: - meta = determineMetaclass(bases, previousMetaclass) - - newClass = meta(name,bases,cdict) - - # this lets the callback replace the class completely, if it wants to - return callback(newClass) - - # introspection data only, not used by inner function - advise.previousMetaclass = previousMetaclass - advise.callback = callback - - # install the advisor - caller_locals['__metaclass__'] = advise - - -def isClassAdvisor(ob): - """True if 'ob' is a class advisor function""" - return isinstance(ob,FunctionType) and hasattr(ob,'previousMetaclass') - - -def determineMetaclass(bases, explicit_mc=None): - """Determine metaclass from 1+ bases and optional explicit __metaclass__""" - - meta = [getattr(b,'__class__',type(b)) for b in bases] - - if explicit_mc is not None: - # The explicit metaclass needs to be verified for compatibility - # as well, and allowed to resolve the incompatible bases, if any - meta.append(explicit_mc) - - if len(meta)==1: - # easy case - return meta[0] - - candidates = minimalBases(meta) # minimal set of metaclasses - - if not candidates: - # they're all "classic" classes - assert(not __python3) # This should not happen under Python 3 - return ClassType - - elif len(candidates)>1: - # We could auto-combine, but for now we won't... - raise TypeError("Incompatible metatypes",bases) - - # Just one, return it - return candidates[0] - - -def minimalBases(classes): - """Reduce a list of base classes to its ordered minimum equivalent""" - - if not __python3: - classes = [c for c in classes if c is not ClassType] - candidates = [] - - for m in classes: - for n in classes: - if issubclass(n,m) and m is not n: - break - else: - # m has no subclasses in 'classes' - if m in candidates: - candidates.remove(m) # ensure that we're later in the list - candidates.append(m) - - return candidates - |