U
e5db3 � @ s� d Z dZddlZddlZddlZddlZddlmZ ddlm Z ddlm
Z
ddlm Z ej Z ej
Z
ejZejZejd ZG d d
� d
�ZeZd d � Zd
d� Zdd� Zdd� Zdd� Zdd� Zdd�dd�Zz ddlZW n e k
r� Y n X ej ZZ dS )z.A Future class similar to the one in PEP 3148.)�Future� wrap_future�isfuture� N� )� base_futures)�events)�
exceptions)�format_helpersc @ s� e Zd ZdZeZdZdZdZdZ dZ
dZ dd�dd�Z e
jZdd� Zd d
� Zed d � �Zejd
d � �Zdd� Zdd� Zdd� Zdd� Zdd� Zdd� Zdd� Zdd �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.)
NF��loopc C s@ |dkrt �� | _n|| _g | _| j�� r� )�format� __class__�__name__�join�
_repr_info�r r r r �__repr__V 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� exception�futureZsource_traceback)�_Future__log_traceback�
_exceptionr r r r
Zcall_exception_handler)r �exc�contextr r r �__del__Z s �
zFuture.__del__c C s | j S �N)r# r r r r �_log_tracebackj s zFuture._log_tracebackc C s t |�rtd��d| _d S )Nz'_log_traceback can only be set to FalseF)�bool�
ValueErrorr# )r �valr r r r) n s c C s | j }|dkrtd��|S )z-Return the event loop the Future is bound to.Nz!Future object is not initialized.)r
� RuntimeErrorr r r r �get_loopt s zFuture.get_loopc C s& d| _ | jtkrdS t| _| �� dS )z�Cancel 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�
_CANCELLED�_Future__schedule_callbacksr r r r �cancel{ s
z
Future.cancelc C sH | j dd� }|sdS g | j dd�< |D ]\}}| jj|| |d� q(dS )z�Internal: Ask the event loop to call all callbacks.
The callbacks are scheduled to be called as soon as possible. Also
clears the callback list.
N�r& )r r
� call_soon)r Z callbacks�callback�ctxr r r Z__schedule_callbacks� s zFuture.__schedule_callbacksc C s
| j tkS )z(Return True if the future was cancelled.)r/ r1 r r r r � cancelled� s zFuture.cancelledc C s
| j tkS )z�Return True if the future is done.
Done means either that a result / exception are available, or that the
future was cancelled.
)r/ r0 r r r r �done� s z Future.donec C s@ | j tkrtj�| j tkr$t�d��d| _| jdk r:| 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) r/ r1 r �CancelledError� _FINISHED�InvalidStateErrorr# r$ �_resultr r r r �result� s
z
Future.resultc C s0 | j tkrtj�| j tkr$t�d��d| _| jS )a& Return the exception that was set on this future.
The exception (or None if no exception was set) is returned only if
the future is done. If the future has been cancelled, raises
CancelledError. If the future isn't done yet, raises
InvalidStateError.
zException is not set.F)r/ r1 r r: r; r< r# r$ r r r r r! � s
zFuture.exceptionr4 c C sB | j tkr | jj|| |d� n |dkr.t�� }| j�||f� dS )z�Add 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.
r4 N)r/ r0 r
r5 � 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||f�qS r r )�.0�fr7 �rA r r �
� s �z/Future.remove_done_callback..N)r �len)r rA Zfiltered_callbacksZ
removed_countr rE r �remove_done_callback� s
�zFuture.remove_done_callbackc C s8 | j tkr t�| j � d| ����|| _t| _ | �� dS )z�Mark the future done and set its result.
If the future is already done when this method is called, raises
InvalidStateError.
�: N)r/ r0 r r< r= r; r2 )r r> r r r �
set_result� s
zFuture.set_resultc C sb | j tkr t�| j � d| ����t|t�r0|� }t|�tkrDtd��|| _t | _ | �
� d| _ dS )z�Mark the future done and set an exception.
If the future is already done when this method is called, raises
InvalidStateError.
rI zPStopIteration interacts badly with generators and cannot be raised into a FutureTN) r/ r0 r r< �
isinstance�type�
StopIteration� TypeErrorr$ r; r2 r# )r r! r r r �
set_exception� s
zFuture.set_exceptionc c s, | � � sd| _| V | � � s$td��| �� S )NTz await wasn't used with future)r9 �_asyncio_future_blockingr- r> r r r r � __await__ s zFuture.__await__)"r �
__module__� __qualname__�__doc__r0 r/ r= r$ r
r rP r# r r Z_future_repr_infor r r' �propertyr) �setterr. r3 r2 r8 r9 r> r! rB rH rJ rO rQ �__iter__r r r r r s:
r c C s, z
| j }W n tk
r Y nX |� S | jS r( )r. �AttributeErrorr
)�futr. r r r � _get_loop s
rZ c C s | � � r dS | �|� dS )z?Helper setting the result only if the future was not cancelled.N)r8 rJ )rY r> r r r � _set_result_unless_cancelled s r[ c C sX t | �}|tjjkr tj| j� S |tjjkr8tj| j� S |tjjkrPtj| j� S | S d S r( )rL �
concurrent�futuresr: r �args� TimeoutErrorr< )r% Z exc_classr r r �_convert_future_exc# s r` c C s^ |� � s t�|�� r | �� | �� s(dS |�� }|dk rH| �t|�� n|�� }| � |� dS )z8Copy state from a future to a concurrent.futures.Future.N)
r9 �AssertionErrorr8 r3 Z set_running_or_notify_cancelr! rO r` r> rJ )r\ �sourcer! r> r r r � _set_concurrent_future_state/ s rc c C sl | � � s t�|�� rdS |� � r$t�| �� r6|�� n2| �� }|dk rV|�t|�� n| �� }|�|� dS )zqInternal helper to copy state from another Future.
The other Future may be a concurrent.futures.Future.
N) r9 ra r8 r3 r! rO r` r> rJ )rb �destr! r> r r r �_copy_future_state> s
re c s� t ��s t�tjj�s td��t ��s._set_statec s2 | � � r.�d ks�� kr"��� n ���j� d S r( )r8 r3 �call_soon_threadsafe)� destination)� dest_looprb � source_loopr r �_call_check_cancelh s
z)_chain_future.._call_check_cancelc sJ �� � r �d k r ��� r d S �d ks,��kr8� �| � n��� �| � d S r( )r8 Z is_closedrh )rb )rg rj ri rk r r �_call_set_stateo s �� z&_chain_future.._call_set_state)r rK r\ r] r rN rZ rB )rb ri rl rm r )rg rj ri rb rk r �
_chain_futureR s � �
rn r
c C sN t | �r | S t| tjj�s(td| ����|dkr8t�� }|�� }t | |� |S )z&Wrap concurrent.futures.Future object.z+concurrent.futures.Future is expected, got N)
r rK r\ r] r ra r r Z
create_futurern )r" r Z
new_futurer r r r | s �
r ) rT �__all__Zconcurrent.futuresr\ r? Zloggingr � r r r r r r0 r1 r; �DEBUGZ STACK_DEBUGr Z _PyFuturerZ r[ r` rc re rn r Z_asyncio� ImportErrorZ_CFuturer r r r � s:
q *