a
i6 @ s d Z dZddlZddlZddlZddlZddlmZ ddl m
Z
ddl m Z ddl m Z dd l m
Z
e
jZe
jZe
jZe
jZejd ZG d
d d ZeZd d
Zdd Zdd Zdd Zdd Zdd ZddddZ z ddl Z W n e y Y n 0 e j ZZ dS )z.A Future class similar to the one in PEP 3148.)Future wrap_futureisfuture N) GenericAlias ) base_futures)events)
exceptions)format_helpersc @ s e Zd ZdZeZdZdZdZdZ dZ
dZ dZ dZ
ddddZejZdd Zd d
ZeeZed d Zejd
d Zdd Zdd Zd)ddZ dd Z dd Z dd Z dd Z d d Z!dd d d Z"d!d" Z#d#d$ Z$d%d& Z%d'd( Z&e&Z'dS )*r a, This class is *almost* compatible with concurrent.futures.Future.
Differences:
- This class is not thread-safe.
- result() and exception() do not take a timeout argument and
raise an exception when the future isn't done yet.
- Callbacks registered with add_done_callback() are always called
via the event loop's call_soon().
- This class is not compatible with the wait() and as_completed()
methods in the concurrent.futures package.
(In Python 3.4 or later we may be able to unify the implementations.)
NFloopc C s@ |du rt | _n|| _g | _| j r )format __class____name__join
_repr_infor r r r __repr__Z s
zFuture.__repr__c C sF | j s
d S | j}| jj d|| d}| jr6| j|d< | j| d S )Nz exception was never retrieved)message exceptionfutureZsource_traceback)_Future__log_traceback
_exceptionr r r r Zcall_exception_handler)r exccontextr r r __del__^ s
zFuture.__del__c C s | j S N)r$ r r r r _log_tracebackp s zFuture._log_tracebackc C s t |rtdd| _d S )Nz'_log_traceback can only be set to FalseF)bool
ValueErrorr$ )r valr r r r* t s c C s | j }|du rtd|S )z-Return the event loop the Future is bound to.Nz!Future object is not initialized.)r RuntimeErrorr r r r get_loopz s zFuture.get_loopc C s2 | j du rt }n t| j }| j|_d| _|S )zCreate the CancelledError to raise if the Future is cancelled.
This should only be called once when handling a cancellation since
it erases the saved context exception value.
N)_cancel_messager CancelledError_cancelled_exc __context__r r& r r r _make_cancelled_error s
z Future._make_cancelled_errorc C s, d| _ | jtkrdS t| _|| _| dS )zCancel the future and schedule callbacks.
If the future is already done or cancelled, return False. Otherwise,
change the future's state to cancelled, schedule the callbacks and
return True.
FT)r$ _state_PENDING
_CANCELLEDr0 _Future__schedule_callbacks)r msgr r r cancel s
z
Future.cancelc C sH | j dd }|sdS g | j dd< |D ]\}}| jj|| |d q(dS )zInternal: Ask the event loop to call all callbacks.
The callbacks are scheduled to be called as soon as possible. Also
clears the callback list.
Nr' )r r call_soon)r Z callbackscallbackctxr r r Z__schedule_callbacks s zFuture.__schedule_callbacksc C s
| j tkS )z(Return True if the future was cancelled.)r6 r8 r r r r cancelled s zFuture.cancelledc C s
| j tkS )zReturn True if the future is done.
Done means either that a result / exception are available, or that the
future was cancelled.
)r6 r7 r r r r done s z Future.donec C sF | j tkr| }|| j tkr*tdd| _| jdur@| j| jS )a Return the result this future represents.
If the future has been cancelled, raises CancelledError. If the
future's result isn't yet available, raises InvalidStateError. If
the future is done and has an exception set, this exception is raised.
zResult is not ready.FN) r6 r8 r5 _FINISHEDr InvalidStateErrorr$ r% _resultr4 r r r result s
z
Future.resultc C s6 | j tkr| }|| j tkr*tdd| _| jS )a& Return the exception that was set on this future.
The exception (or None if no exception was set) is returned only if
the future is done. If the future has been cancelled, raises
CancelledError. If the future isn't done yet, raises
InvalidStateError.
zException is not set.F)r6 r8 r5 rB r rC r$ r% r4 r r r r" s
zFuture.exceptionr< c C sB | j tkr | jj|| |d n |du r.t }| j||f dS )zAdd a callback to be run when the future becomes done.
The callback is called with a single argument - the future object. If
the future is already done when this is called, the callback is
scheduled with call_soon.
r< N)r6 r7 r r= contextvarsZ copy_contextr append)r fnr' r r r add_done_callback s
zFuture.add_done_callbackc s< fdd| j D }t| j t| }|r8|| j dd< |S )z}Remove all instances of a callback from the "call when done" list.
Returns the number of callbacks removed.
c s g | ]\}}| kr||fqS r r ).0fr? rH r r
s z/Future.remove_done_callback..N)r len)r rH Zfiltered_callbacksZ
removed_countr rL r remove_done_callback s
zFuture.remove_done_callbackc C s8 | j tkr t| j d| || _t| _ | dS )zMark the future done and set its result.
If the future is already done when this method is called, raises
InvalidStateError.
: N)r6 r7 r rC rD rB r9 )r rE r r r
set_result s
zFuture.set_resultc C sb | j tkr t| j d| t|tr0| }t|tu rDtd|| _t | _ |
d| _ dS )zMark the future done and set an exception.
If the future is already done when this method is called, raises
InvalidStateError.
rP zPStopIteration interacts badly with generators and cannot be raised into a FutureTN) r6 r7 r rC
isinstancetype
StopIteration TypeErrorr% rB r9 r$ )r r" r r r
set_exception s
zFuture.set_exceptionc c s, | sd| _| V | s$td| S )NTz await wasn't used with future)rA _asyncio_future_blockingr. rE r r r r __await__ s zFuture.__await__)N)(r
__module__ __qualname____doc__r7 r6 rD r% r r r0 r2 rW r$ r r Z_future_repr_infor r r( classmethodr __class_getitem__propertyr* setterr/ r5 r; r9 r@ rA rE r" rI rO rQ rV rX __iter__r r r r r sB
r c C s* z
| j }W n ty Y n0 | S | jS r) )r/ AttributeErrorr )futr/ r r r _get_loop( s
rc c C s | r dS | | dS )z?Helper setting the result only if the future was not cancelled.N)r@ rQ )rb rE r r r _set_result_unless_cancelled4 s rd c C sX t | }|tjju r tj| j S |tjju r8tj| j S |tjju rPtj| j S | S d S r) )rS
concurrentfuturesr1 r args TimeoutErrorrC )r& Z exc_classr r r _convert_future_exc; s ri c C sR | r| | s dS | }|dur<| t| n| }| | dS )z8Copy state from a future to a concurrent.futures.Future.N)r@ r; set_running_or_notify_cancelr" rV ri rE rQ )re sourcer" rE r r r _set_concurrent_future_stateG s rl c C sT | r dS | r | n2| }|dur>|t| n| }|| dS )zqInternal helper to copy state from another Future.
The other Future may be a concurrent.futures.Future.
N)r@ r; r" rV ri rE rQ )rk destr" rE r r r _copy_future_stateV s
rn c s t s ttjjs tdt s._set_statec s2 | r.d u s u r" n j d S r) )r@ r; call_soon_threadsafe) destination) dest_looprk source_loopr r _call_check_cancel s
z)_chain_future.._call_check_cancelc sJ r d ur r d S d u s,u r8 | n | d S r) )r@ Z is_closedrq )rk )rp rs rr rt r r _call_set_state s z&_chain_future.._call_set_state)r rR re rf r rU rc rI )rk rr ru rv r )rp rs rr rk rt r
_chain_futurej s
rw r c C s2 t | r | S |du r t }| }t| | |S )z&Wrap concurrent.futures.Future object.N)r r r
Z
create_futurerw )r# r Z
new_futurer r r r s
r ) r[ __all__concurrent.futuresre rF loggingr typesr r r r r
r r7 r8 rB DEBUGZ STACK_DEBUGr Z _PyFuturerc rd ri rl rn rw r Z_asyncio ImportErrorZ_CFuturer r r r s>
*