ó P'—^c@@s›dZddlmZddlZddlZddlZdgZejddkZdd„Z de fd„ƒYZ d e fd „ƒYZ d „ZdS( s« "Safe weakrefs", originally from pyDispatcher. Provides a way to safely weakref any function, including bound methods (which aren't handled by the core weakref module). i(tabsolute_importNtsafe_reficC@s|t|ddƒdk rOt|dƒs<tdj|ƒƒ‚td|d|ƒSt|ƒrktj||ƒStj|ƒSdS(sReturn a *safe* weak reference to a callable target :param target: the object to be weakly referenced, if it's a bound method reference, will create a :class:`BoundMethodWeakref`, otherwise creates a simple :class:`weakref.ref`. :keyword on_delete: if provided, will have a hard reference stored to the callable to be called after the safe reference goes out of scope with the reference object, (either a :class:`weakref.ref` or a :class:`BoundMethodWeakref`) as argument. t__self__t__func__scsafe_ref target {0!r} has __self__, but no __func__: don't know how to create referencettargett on_deleteN( tgetattrtNonethasattrtAssertionErrortformattget_bound_method_weakreftcallabletweakreftref(RR((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyRs   tBoundMethodWeakrefcB@s€eZdZejƒZdd„Zdd„Zd„Z e e ƒZ d„Z e Z d„Z e Zesud„Znd„ZRS( sõ'Safe' and reusable weak references to instance methods. BoundMethodWeakref objects provide a mechanism for referencing a bound method without requiring that the method object itself (which is normally a transient object) is kept alive. Instead, the BoundMethodWeakref object keeps weak references to both the object and the function which together define the instance method. .. attribute:: key the identity key for the reference, calculated by the class's :meth:`calculate_key` method applied to the target instance method .. attribute:: deletion_methods sequence of callable objects taking single argument, a reference to this object which will be called when *either* the target object or target function is garbage collected (i.e. when this object becomes invalid). These are specified as the on_delete parameters of :func:`safe_ref` calls. .. attribute:: weak_self weak reference to the target object .. attribute:: weak_fun weak reference to the target function .. attribute:: _all_instances class attribute pointing to all live BoundMethodWeakref objects indexed by the class's `calculate_key(target)` method applied to the target objects. This weak value dictionary is used to short-circuit creation so that multiple references to the same (object, function) pair produce the same BoundMethodWeakref instance. cO@s„|j|ƒ}|jj|ƒ}|dk rA|jj|ƒ|Stt|ƒj|ƒ}||j|<|j ||||Ž|SdS(sýCreate new instance or return current instance Basically this method of construction allows us to short-circuit creation of references to already- referenced instance methods. The key corresponding to the target is calculated, and if there is already an existing reference, that is returned, with its deletionMethods attribute updated. Otherwise the new instance is created and registered in the table of already-referenced methods. N( t calculate_keyt_all_instancestgetRtdeletion_methodstappendtsuperRt__new__t__init__(tclsRRt argumentstnamedtkeytcurrenttbase((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyR\s   cC@s…|d„}|g|_|j|ƒ|_tj|j|ƒ|_tj|j|ƒ|_t |jƒ|_ t |jj ƒ|_ dS(s’Return a weak-reference-like instance for a bound method :param target: the instance-method target for the weak reference, must have `__self__` and `__func__` attributes and be reconstructable via:: target.__func__.__get__(target.__self__) which is true of built-in instance methods. :keyword on_delete: optional callback which will be called when this weak reference ceases to be valid (i.e. either the object or the function is garbage collected). Should take a single argument, which will be passed a pointer to this object. cS@s·|j}|j2y|jj|j=Wntk r8nXxw|D]o}yt|ƒrb||ƒnWq@tk r®}ytjƒWq¯t k rªdj |||ƒGHq¯Xq@Xq@WdS(s=Set self.is_dead to true when method or instance is destroyeds6Exception during saferef {0} cleanup function {1}: {2}N( Rt __class__RRtKeyErrorR t Exceptiont tracebackt print_exctAttributeErrorR (tweaktselftmethodstfunctiontexc((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pytremove†s      N( RRRR RRt weak_selfRtweak_funtstrt self_namet__name__tfun_name(R%RRR)((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyRts  cC@st|jƒt|jƒfS(s±Calculate the reference key for this reference Currently this is a two-tuple of the `id()`'s of the target object and the target function respectively. (tidRR(RR((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyR scC@s"djt|ƒj|j|jƒS(s,Give a friendly representation of the objects{0}( {1}.{2} )(R ttypeR.R-R/(R%((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyt__str__©s cC@s |ƒdk S(s&Whether we are still a valid referenceN(R(R%((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyt__bool__³scC@s;t||jƒs(t|jt|ƒƒSt|j|jƒS(sCompare with another reference(t isinstanceRtcmpR1R(R%tother((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyt__cmp__¹scC@sD|jƒ}|dk r@|jƒ}|dk r@|j|ƒSndS(sMReturn a strong reference to the bound method If the target cannot be retrieved, then will return None, otherwise return a bound instance method for our object and function. Note: You may call this method any number of times, as it does not invalidate the reference. N(R*RR+t__get__(R%RR'((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyt__call__¿s    N(R.t __module__t__doc__R tWeakValueDictionaryRRRRRt classmethodR2t__repr__R3t __nonzero__tPY3R7R9(((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyR-s+   ,     tBoundNonDescriptorMethodWeakrefcB@s#eZdZdd„Zd„ZRS(sáA specialized :class:`BoundMethodWeakref`, for platforms where instance methods are not descriptors. It assumes that the function name and the target attribute name are the same, instead of assuming that the function is a descriptor. This approach is equally fast, but not 100% reliable because functions can be stored on an attribute named differenty than the function's name such as in:: >>> class A(object): ... pass >>> def foo(self): ... return 'foo' >>> A.bar = foo But this shouldn't be a common use case. So, on platforms where methods aren't descriptors (such as Jython) this implementation has the advantage of working in the most cases. cC@s>t|j|jƒ|ks!t‚tt|ƒj||ƒdS(s‘Return a weak-reference-like instance for a bound method :param target: the instance-method target for the weak reference, must have `__self__` and `__func__` attributes and be reconstructable via:: target.__func__.__get__(target.__self__) which is true of built-in instance methods. :keyword on_delete: optional callback which will be called when this weak reference ceases to be valid (i.e. either the object or the function is garbage collected). Should take a single argument, which will be passed a pointer to this object. N(RRR.R RRAR(R%RR((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyRæs!cC@sG|jƒ}|dk rC|jƒ}|dk rCt||jƒSndS(sNReturn a strong reference to the bound method If the target cannot be retrieved, then will return None, otherwise return a bound instance method for our object and function. Note: You may call this method any number of times, as it does not invalidate the reference. N(R*RR+RR.(R%RR'((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyR9üs    N(R.R:R;RRR9(((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyRAÑs cC@s9t|dƒr"td|d|ƒStd|d|ƒSdS(s„Instantiates the appropiate :class:`BoundMethodWeakRef`, depending on the details of the underlying class method implementation.R8RRN(RRRA(RR((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyR s (R;t __future__RtsysR!R t__all__t version_infoR@RRtobjectRRAR (((s?/tmp/pip-unpacked-wheel-gV1wwp/celery/utils/dispatch/saferef.pyts     ¤D