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Editing: contextlib.cpython-38.pyc
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See PEP 343.� N)�deque��wraps�� MethodType�asynccontextmanager�contextmanager�closing� nullcontext�AbstractContextManager�AbstractAsyncContextManager�AsyncExitStack�ContextDecorator� ExitStack�redirect_stdout�redirect_stderr�suppressc @ s2 e Zd ZdZdd� Zejdd� �Zedd� �Z dS ) r z,An abstract base class for context managers.c C s | S �z0Return `self` upon entering the runtime context.� ��selfr r �"/usr/lib64/python3.8/contextlib.py� __enter__ s z AbstractContextManager.__enter__c C s dS �z9Raise any exception triggered within the runtime context.Nr �r �exc_type� exc_value� tracebackr r r �__exit__ s z AbstractContextManager.__exit__c C s | t krt�|dd�S tS )Nr r )r �_collections_abc�_check_methods�NotImplemented��cls�Cr r r �__subclasshook__ s z'AbstractContextManager.__subclasshook__N) �__name__� __module__� __qualname__�__doc__r �abc�abstractmethodr � classmethodr% r r r r r s c @ s2 e Zd ZdZdd� Zejdd� �Zedd� �Z dS ) r z9An abstract base class for asynchronous context managers.c � s | S r r r r r r � __aenter__' s z&AbstractAsyncContextManager.__aenter__c � s dS r r r r r r � __aexit__+ s z%AbstractAsyncContextManager.__aexit__c C s | t krt�|dd�S tS )Nr- r. )r r r r! r" r r r r% 0 s �z,AbstractAsyncContextManager.__subclasshook__N) r& r' r( r) r- r* r+ r. r, r% r r r r r # s c @ s e Zd ZdZdd� Zdd� ZdS )r zJA base class or mixin that enables context managers to work as decorators.c C s | S )a6 Return a recreated instance of self. Allows an otherwise one-shot context manager like _GeneratorContextManager to support use as a decorator via implicit recreation. This is a private interface just for _GeneratorContextManager. See issue #11647 for details. r r r r r � _recreate_cm; s z ContextDecorator._recreate_cmc s t � �� �fdd��}|S )Nc s* �� � � � | |�W 5 Q R � S Q R X d S �N)r/ ��args�kwds��funcr r r �innerH s z(ContextDecorator.__call__.<locals>.innerr )r r5 r6 r r4 r �__call__G s zContextDecorator.__call__N)r& r' r( r) r/ r7 r r r r r 8 s c @ s e Zd ZdZdd� ZdS )� _GeneratorContextManagerBasezBShared functionality for @contextmanager and @asynccontextmanager.c C sJ |||�| _ ||| | _| _| _t|dd �}|d kr@t| �j}|| _d S )Nr) )�genr5 r2 r3 �getattr�typer) )r r5 r2 r3 �docr r r �__init__R s z%_GeneratorContextManagerBase.__init__N)r& r' r( r) r= r r r r r8 O s r8 c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS ) �_GeneratorContextManagerz%Helper for @contextmanager decorator.c C s | � | j| j| j�S r0 )� __class__r5 r2 r3 r r r r r/ f s z%_GeneratorContextManager._recreate_cmc C s< | ` | `| `z t| j�W S tk r6 td�d �Y nX d S �Nzgenerator didn't yield)r2 r3 r5 �nextr9 � StopIteration� RuntimeErrorr r r r r l s z"_GeneratorContextManager.__enter__c C s |d kr8zt | j� W n tk r, Y dS X td��n�|d krF|� }z| j�|||� W n� tk r� } z||k W Y �S d }~X Y nt tk r� } z4||kr�W Y �&dS |tkr�|j|kr�W Y � dS � W 5 d }~X Y n$ t�� d |kr�Y dS � Y nX td��d S )NF�generator didn't stop� z#generator didn't stop after throw())rA r9 rB rC �throw� __cause__�sys�exc_info)r r; �valuer �excr r r r u s. z!_GeneratorContextManager.__exit__N)r& r' r( r) r/ r r r r r r r> a s r> c @ s e Zd ZdZdd� Zdd� ZdS )� _AsyncGeneratorContextManagerz Helper for @asynccontextmanager.c � s6 z| j �� I d H W S tk r0 td�d �Y nX d S r@ )r9 � __anext__�StopAsyncIterationrC r r r r r- � s z(_AsyncGeneratorContextManager.__aenter__c � s& |d kr>z| j �� I d H W n tk r2 Y d S X td��n�|d krL|� }z"| j �|||�I d H td��W n� tk r� } z||k W Y �S d }~X Y n� tk r� } z:||kr�W Y �,dS t|ttf�r�|j|kr�W Y � dS � W 5 d }~X Y n0 tk �r } z||k �r� W 5 d }~X Y nX d S )NrD z$generator didn't stop after athrow()F) r9 rM rN rC �athrow� isinstancerB rG � BaseException)r �typrJ r rK r r r r. � s. z'_AsyncGeneratorContextManager.__aexit__N)r& r' r( r) r- r. r r r r rL � s rL c s t � �� fdd��}|S )a� @contextmanager decorator. Typical usage: @contextmanager def some_generator(<arguments>): <setup> try: yield <value> finally: <cleanup> This makes this: with some_generator(<arguments>) as <variable>: <body> equivalent to this: <setup> try: <variable> = <value> <body> finally: <cleanup> c s t � | |�S r0 )r> r1 �r5 r r �helper� s z contextmanager.<locals>.helperr �r5 rT r rS r r � s c s t � �� fdd��}|S )a� @asynccontextmanager decorator. Typical usage: @asynccontextmanager async def some_async_generator(<arguments>): <setup> try: yield <value> finally: <cleanup> This makes this: async with some_async_generator(<arguments>) as <variable>: <body> equivalent to this: <setup> try: <variable> = <value> <body> finally: <cleanup> c s t � | |�S r0 )rL r1 rS r r rT s z#asynccontextmanager.<locals>.helperr rU r rS r r � s c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS ) r a2 Context to automatically close something at the end of a block. Code like this: with closing(<module>.open(<arguments>)) as f: <block> is equivalent to this: f = <module>.open(<arguments>) try: <block> finally: f.close() c C s || _ d S r0 ��thing)r rW r r r r= & s zclosing.__init__c C s | j S r0 rV r r r r r ( s zclosing.__enter__c G s | j �� d S r0 )rW �close)r rI r r r r * s zclosing.__exit__N�r& r' r( r) r= r r r r r r r s c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS )�_RedirectStreamNc C s || _ g | _d S r0 )� _new_target� _old_targets)r � new_targetr r r r= 2 s z_RedirectStream.__init__c C s* | j �tt| j�� tt| j| j� | jS r0 )r\ �appendr: rH �_stream�setattrr[ r r r r r 7 s z_RedirectStream.__enter__c C s t t| j| j�� � d S r0 )r` rH r_ r\ �pop�r �exctype�excinst�exctbr r r r < s z_RedirectStream.__exit__)r& r' r( r_ r= r r r r r r rZ . s rZ c @ s e Zd ZdZdZdS )r aA Context manager for temporarily redirecting stdout to another file. # How to send help() to stderr with redirect_stdout(sys.stderr): help(dir) # How to write help() to a file with open('help.txt', 'w') as f: with redirect_stdout(f): help(pow) �stdoutN�r& r' r( r) r_ r r r r r @ s c @ s e Zd ZdZdZdS )r zCContext manager for temporarily redirecting stderr to another file.�stderrNrg r r r r r P s c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS ) r a? Context manager to suppress specified exceptions After the exception is suppressed, execution proceeds with the next statement following the with statement. with suppress(FileNotFoundError): os.remove(somefile) # Execution still resumes here if the file was already removed c G s || _ d S r0 )� _exceptions)r � exceptionsr r r r= a s zsuppress.__init__c C s d S r0 r r r r r r d s zsuppress.__enter__c C s |d k ot || j�S r0 )� issubclassri rb r r r r g s zsuppress.__exit__NrY r r r r r V s c @ sh e Zd ZdZedd� �Zedd� �Zdd� Zdd � Zd d � Z d d � Z dd� Z de _ dd� Z ddd�ZdS )�_BaseExitStackz.A base class for ExitStack and AsyncExitStack.c C s t || �S r0 r ��cm�cm_exitr r r �_create_exit_wrapperw s z#_BaseExitStack._create_exit_wrapperc s � ��fdd�}|S )Nc s �� �� d S r0 r �r rK �tb�r2 �callbackr3 r r � _exit_wrapper} s z8_BaseExitStack._create_cb_wrapper.<locals>._exit_wrapperr �rt r2 r3 ru r rs r �_create_cb_wrapper{ s z!_BaseExitStack._create_cb_wrapperc C s t � | _d S r0 )r �_exit_callbacksr r r r r= � s z_BaseExitStack.__init__c C s t | �� }| j|_t� | _|S )z@Preserve the context stack by transferring it to a new instance.)r; rx r )r � new_stackr r r �pop_all� s z_BaseExitStack.pop_allc C sB t |�}z |j}W n tk r0 | �|� Y nX | �||� |S )a Registers a callback with the standard __exit__ method signature. Can suppress exceptions the same way __exit__ method can. Also accepts any object with an __exit__ method (registering a call to the method instead of the object itself). )r; r �AttributeError�_push_exit_callback� _push_cm_exit�r �exit�_cb_type� exit_methodr r r �push� s z_BaseExitStack.pushc C s( t |�}|j}|�|�}| �||� |S )z�Enters the supplied context manager. If successful, also pushes its __exit__ method as a callback and returns the result of the __enter__ method. )r; r r r} �r rn �_cm_type�_exit�resultr r r � enter_context� s z _BaseExitStack.enter_contextc O s� t | �dkr| ^}}} nV| s&td��nHd|krZ|�d�}| ^}} ddl}|jdtdd� ntdt | �d ��|j|f| �|�}||_|�|� |S ) z\Registers an arbitrary callback and arguments. Cannot suppress exceptions. � zBdescriptor 'callback' of '_BaseExitStack' object needs an argumentrt r N�4Passing 'callback' as keyword argument is deprecated�� stacklevelz8callback expected at least 1 positional argument, got %drE ) �len� TypeErrorra �warnings�warn�DeprecationWarningrw � __wrapped__r| �r2 r3 r rt r� ru r r r rt � s& � � z_BaseExitStack.callback�#($self, callback, /, *args, **kwds)c C s | � ||�}| �|d� dS )z;Helper to correctly register callbacks to __exit__ methods.TN)rp r| �r rn ro ru r r r r} � s z _BaseExitStack._push_cm_exitTc C s | j �||f� d S r0 )rx r^ )r rt �is_syncr r r r| � s z"_BaseExitStack._push_exit_callbackN)T)r& r' r( r) � staticmethodrp rw r= rz r� r� rt �__text_signature__r} r| r r r r rl t s rl c @ s( e Zd ZdZdd� Zdd� Zdd� ZdS ) r a� Context manager for dynamic management of a stack of exit callbacks. For example: with ExitStack() as stack: files = [stack.enter_context(open(fname)) for fname in filenames] # All opened files will automatically be closed at the end of # the with statement, even if attempts to open files later # in the list raise an exception. c C s | S r0 r r r r r r � s zExitStack.__enter__c s� |d d k }t �� d � � fdd�}d}d}| jr�| j�� \}}|sHt�z||� r^d}d}d}W q, t �� }||d |d � d}|}Y q,X q,|r�z|d j} |d �W n tk r� | |d _� Y nX |o�|S )Nr rE c s4 | j }||krd S |d ks*|� kr$q*|} q || _ d S r0 �� __context__��new_exc�old_exc� exc_context�� frame_excr r �_fix_exception_context� s z2ExitStack.__exit__.<locals>._fix_exception_contextFT�NNN)rH rI rx ra �AssertionErrorr� rQ ) r � exc_details� received_excr� �suppressed_exc� pending_raiser� �cb�new_exc_details� fixed_ctxr r� r r � s4 zExitStack.__exit__c C s | � ddd� dS �z%Immediately unwind the context stack.N)r r r r r rX s zExitStack.closeN)r& r' r( r) r r rX r r r r r � s 1c @ sf e Zd ZdZedd� �Zedd� �Zdd� Zdd � Zd d � Z d e _ d d� Z dd� Z dd� Z dd� ZdS )r a� Async context manager for dynamic management of a stack of exit callbacks. For example: async with AsyncExitStack() as stack: connections = [await stack.enter_async_context(get_connection()) for i in range(5)] # All opened connections will automatically be released at the # end of the async with statement, even if attempts to open a # connection later in the list raise an exception. c C s t || �S r0 r rm r r r �_create_async_exit_wrapper& s z)AsyncExitStack._create_async_exit_wrapperc s � ��fdd�}|S )Nc � s �� ��I d H d S r0 r rq rs r r ru , s z>AsyncExitStack._create_async_cb_wrapper.<locals>._exit_wrapperr rv r rs r �_create_async_cb_wrapper* s z'AsyncExitStack._create_async_cb_wrapperc � s. t |�}|j}|�|�I dH }| �||� |S )z�Enters the supplied async context manager. If successful, also pushes its __aexit__ method as a callback and returns the result of the __aenter__ method. N)r; r. r- �_push_async_cm_exitr� r r r �enter_async_context0 s z"AsyncExitStack.enter_async_contextc C sD t |�}z |j}W n tk r2 | �|d� Y nX | �||� |S )a# Registers a coroutine function with the standard __aexit__ method signature. Can suppress exceptions the same way __aexit__ method can. Also accepts any object with an __aexit__ method (registering a call to the method instead of the object itself). F)r; r. r{ r| r� r~ r r r �push_async_exit< s z AsyncExitStack.push_async_exitc O s� t | �dkr| ^}}} nV| s&td��nHd|krZ|�d�}| ^}} ddl}|jdtdd� ntdt | �d ��|j|f| �|�}||_|�|d � |S ) zfRegisters an arbitrary coroutine function and arguments. Cannot suppress exceptions. r� zMdescriptor 'push_async_callback' of 'AsyncExitStack' object needs an argumentrt r Nr� r� zCpush_async_callback expected at least 1 positional argument, got %drE F) r� r� ra r� r� r� r� r� r| r� r r r �push_async_callbackN s& � � z"AsyncExitStack.push_async_callbackr� c � s | � ddd�I dH dS r� )r. r r r r �aclosek s zAsyncExitStack.aclosec C s | � ||�}| �|d� dS )zLHelper to correctly register coroutine function to __aexit__ method.FN)r� r| r� r r r r� o s z"AsyncExitStack._push_async_cm_exitc � s | S r0 r r r r r r- u s zAsyncExitStack.__aenter__c � s� |d d k }t �� d � � fdd�}d}d}| jr�| j�� \}}z0|rP||� }n||� I d H }|rnd}d}d}W q, t �� } || d |d � d}| }Y q,X q,|r�z|d j} |d �W n tk r� | |d _� Y nX |o�|S )Nr rE c s4 | j }||krd S |d ks*|� kr$q*|} q || _ d S r0 r� r� r� r r r� ~ s z8AsyncExitStack.__aexit__.<locals>._fix_exception_contextFTr� )rH rI rx ra r� rQ ) r r� r� r� r� r� r� r� � cb_suppressr� r� r r� r r. x s8 zAsyncExitStack.__aexit__N)r& r' r( r) r� r� r� r� r� r� r� r� r� r- r. r r r r r s c @ s* e Zd ZdZd dd�Zdd� Zdd� ZdS ) r aO Context manager that does no additional processing. Used as a stand-in for a normal context manager, when a particular block of code is only sometimes used with a normal context manager: cm = optional_cm if condition else nullcontext() with cm: # Perform operation, using optional_cm if condition is True Nc C s || _ d S r0 �� enter_result)r r� r r r r= � s znullcontext.__init__c C s | j S r0 r� r r r r r � s znullcontext.__enter__c G s d S r0 r )r �excinfor r r r � s znullcontext.__exit__)NrY r r r r r � s ) r) r* rH r � collectionsr � functoolsr �typesr �__all__�ABCr r �objectr r8 r> rL r r r rZ r r r rl r r r r r r r �<module> sN � �D �.!! `E
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