U
    }®ct  ã                   @   s¢   d Z ddlmZ G dd„ dƒZG dd„ deƒZG dd„ deƒZG d	d
„ d
eƒZG dd„ deƒZG dd„ deƒZG dd„ deƒZ	G dd„ deƒZ
G dd„ deƒZdS )z~
Helpers to manipulate deferred DDL statements that might need to be adjusted or
discarded within when executing a migration.
é    )Údeepcopyc                   @   s@   e Zd ZdZdd„ Zdd„ Zdd„ Zdd	„ Zd
d„ Zdd„ Z	dS )Ú	Referencez0Base class that defines the reference interface.c                 C   s   dS )zU
        Return whether or not this instance references the specified table.
        F© ©ÚselfÚtabler   r   úE/tmp/pip-unpacked-wheel-7m9rsep5/django/db/backends/ddl_references.pyÚreferences_table   s    zReference.references_tablec                 C   s   dS )zV
        Return whether or not this instance references the specified column.
        Fr   ©r   r   Úcolumnr   r   r   Úreferences_column   s    zReference.references_columnc                 C   s   dS )zI
        Rename all references to the old_name to the new_table.
        Nr   ©r   Ú	old_tableÚ	new_tabler   r   r   Úrename_table_references   s    z!Reference.rename_table_referencesc                 C   s   dS )zL
        Rename all references to the old_column to the new_column.
        Nr   ©r   r   Ú
old_columnÚ
new_columnr   r   r   Úrename_column_references   s    z"Reference.rename_column_referencesc                 C   s   d| j jt| ƒf S )Nz<%s %r>)Ú	__class__Ú__name__Ústr©r   r   r   r   Ú__repr__#   s    zReference.__repr__c                 C   s   t dƒ‚d S )Nz>Subclasses must define how they should be converted to string.)ÚNotImplementedErrorr   r   r   r   Ú__str__&   s    zReference.__str__N)
r   Ú
__module__Ú__qualname__Ú__doc__r	   r   r   r   r   r   r   r   r   r   r      s   r   c                   @   s0   e Zd ZdZdd„ Zdd„ Zdd„ Zdd	„ Zd
S )ÚTablezHold a reference to a table.c                 C   s   || _ || _d S ©N)r   Ú
quote_name)r   r   r!   r   r   r   Ú__init__-   s    zTable.__init__c                 C   s
   | j |kS r    ©r   r   r   r   r   r	   1   s    zTable.references_tablec                 C   s   | j |kr|| _ d S r    r#   r   r   r   r   r   4   s    
zTable.rename_table_referencesc                 C   s   |   | j¡S r    )r!   r   r   r   r   r   r   8   s    zTable.__str__N)r   r   r   r   r"   r	   r   r   r   r   r   r   r   *   s
   r   c                   @   s(   e Zd ZdZdd„ Zdd„ Zdd„ ZdS )	ÚTableColumnsz9Base class for references to multiple columns of a table.c                 C   s   || _ || _d S r    ©r   Úcolumns)r   r   r&   r   r   r   r"   ?   s    zTableColumns.__init__c                 C   s   | j |ko|| jkS r    r%   r
   r   r   r   r   C   s    zTableColumns.references_columnc                 C   s4   | j |kr0t| jƒD ]\}}||kr|| j|< qd S r    )r   Ú	enumerater&   )r   r   r   r   Úindexr   r   r   r   r   F   s    
z%TableColumns.rename_column_referencesN)r   r   r   r   r"   r   r   r   r   r   r   r$   <   s   r$   c                       s*   e Zd ZdZd‡ fdd„	Zdd„ Z‡  ZS )ÚColumnsz(Hold a reference to one or many columns.r   c                    s   || _ || _tƒ  ||¡ d S r    )r!   Úcol_suffixesÚsuperr"   )r   r   r&   r!   r*   ©r   r   r   r"   P   s    zColumns.__init__c                    s*   ‡fdd„‰ d  ‡ fdd„tˆjƒD ƒ¡S )Nc                    sB   ˆ   | ¡}zˆ j| }|r&d ||¡}W n tk
r<   Y nX |S ©Nz{} {})r!   r*   ÚformatÚ
IndexError©r   ÚidxÚcolÚsuffixr   r   r   Úcol_strV   s    

z Columns.__str__.<locals>.col_strú, c                 3   s   | ]\}}ˆ ||ƒV  qd S r    r   ©Ú.0r1   r   ©r4   r   r   Ú	<genexpr>`   s     z"Columns.__str__.<locals>.<genexpr>©Újoinr'   r&   r   r   ©r4   r   r   r   U   s    
zColumns.__str__)r   ©r   r   r   r   r"   r   Ú__classcell__r   r   r,   r   r)   M   s   r)   c                       s(   e Zd ZdZ‡ fdd„Zdd„ Z‡  ZS )Ú	IndexNamez"Hold a reference to an index name.c                    s   || _ || _tƒ  ||¡ d S r    )r3   Úcreate_index_namer+   r"   )r   r   r&   r3   r@   r,   r   r   r"   f   s    zIndexName.__init__c                 C   s   |   | j| j| j¡S r    )r@   r   r&   r3   r   r   r   r   r   k   s    zIndexName.__str__r=   r   r   r,   r   r?   c   s   r?   c                       s&   e Zd Zd‡ fdd„	Zdd„ Z‡  ZS )ÚIndexColumnsr   c                    s   || _ tƒ  ||||¡ d S r    )Ú	opclassesr+   r"   )r   r   r&   r!   r*   rB   r,   r   r   r"   p   s    zIndexColumns.__init__c                    s*   ‡fdd„‰ d  ‡ fdd„tˆjƒD ƒ¡S )Nc                    sP   d  ˆ  | ¡ˆ j| ¡}zˆ j| }|r4d  ||¡}W n tk
rJ   Y nX |S r-   )r.   r!   rB   r*   r/   r0   r   r   r   r4   u   s    
z%IndexColumns.__str__.<locals>.col_strr5   c                 3   s   | ]\}}ˆ ||ƒV  qd S r    r   r6   r8   r   r   r9   �   s     z'IndexColumns.__str__.<locals>.<genexpr>r:   r   r   r<   r   r   t   s    zIndexColumns.__str__)r   r   )r   r   r   r"   r   r>   r   r   r,   r   rA   o   s   rA   c                       sX   e Zd ZdZ‡ fdd„Z‡ fdd„Z‡ fdd„Z‡ fdd	„Z‡ fd
d„Zdd„ Z	‡  Z
S )ÚForeignKeyNamez'Hold a reference to a foreign key name.c                    s*   t ||ƒ| _|| _|| _tƒ  ||¡ d S r    )r$   Úto_referenceÚsuffix_templateÚcreate_fk_namer+   r"   )r   Z
from_tableZfrom_columnsÚto_tableZ
to_columnsrE   rF   r,   r   r   r"   ‡   s    zForeignKeyName.__init__c                    s   t ƒ  |¡p| j |¡S r    )r+   r	   rD   r   r,   r   r   r	   �   s    zForeignKeyName.references_tablec                    s   t ƒ  ||¡p| j ||¡S r    )r+   r   rD   r
   r,   r   r   r   �   s    þz ForeignKeyName.references_columnc                    s    t ƒ  ||¡ | j ||¡ d S r    )r+   r   rD   r   r,   r   r   r   –   s    z&ForeignKeyName.rename_table_referencesc                    s$   t ƒ  |||¡ | j |||¡ d S r    )r+   r   rD   r   r,   r   r   r   š   s    z'ForeignKeyName.rename_column_referencesc                 C   s.   | j | jj| jjd dœ }|  | j| j|¡S )Nr   )rG   Z	to_column)rE   rD   r   r&   rF   )r   r3   r   r   r   r   ž   s
    
þzForeignKeyName.__str__)r   r   r   r   r"   r	   r   r   r   r   r>   r   r   r,   r   rC   „   s   rC   c                   @   s@   e Zd ZdZdd„ Zdd„ Zdd„ Zdd	„ Zd
d„ Zdd„ Z	dS )Ú	Statementzò
    Statement template and formatting parameters container.

    Allows keeping a reference to a statement without interpolating identifiers
    that might have to be adjusted if they're referencing a table or column
    that is removed
    c                 K   s   || _ || _d S r    ©ÚtemplateÚparts)r   rJ   rK   r   r   r   r"   ®   s    zStatement.__init__c                    s   t ‡ fdd„| j ¡ D ƒƒS )Nc                 3   s"   | ]}t |d ƒo| ˆ ¡V  qdS )r	   N)Úhasattrr	   ©r7   Úpartr#   r   r   r9   ³   s   ÿz-Statement.references_table.<locals>.<genexpr>©ÚanyrK   Úvaluesr   r   r#   r   r	   ²   s    þzStatement.references_tablec                    s   t ‡ ‡fdd„| j ¡ D ƒƒS )Nc                 3   s$   | ]}t |d ƒo| ˆˆ ¡V  qdS )r   N)rL   r   rM   ©r   r   r   r   r9   ¹   s   ÿz.Statement.references_column.<locals>.<genexpr>rO   r
   r   rR   r   r   ¸   s    þzStatement.references_columnc                 C   s*   | j  ¡ D ]}t|dƒr
| ||¡ q
d S )Nr   )rK   rQ   rL   r   )r   r   r   rN   r   r   r   r   ¾   s    
z!Statement.rename_table_referencesc                 C   s,   | j  ¡ D ]}t|dƒr
| |||¡ q
d S )Nr   )rK   rQ   rL   r   )r   r   r   r   rN   r   r   r   r   Ã   s    
z"Statement.rename_column_referencesc                 C   s   | j | j S r    rI   r   r   r   r   r   È   s    zStatement.__str__N)
r   r   r   r   r"   r	   r   r   r   r   r   r   r   r   rH   ¦   s   rH   c                       s8   e Zd Z‡ fdd„Z‡ fdd„Zdd„ Zdd„ Z‡  ZS )	ÚExpressionsc                    s@   || _ || _|| _dd„ | j j | jg¡D ƒ}tƒ  ||¡ d S )Nc                 S   s   g | ]}|j j‘qS r   )Útargetr   )r7   r2   r   r   r   Ú
<listcomp>Ñ   s     z(Expressions.__init__.<locals>.<listcomp>)ÚcompilerÚexpressionsÚquote_valueÚqueryÚ	_gen_colsr+   r"   )r   r   rW   rV   rX   r&   r,   r   r   r"   Í   s
    zExpressions.__init__c                    sR   | j |krd S t| jƒ}g | _| jj |g¡D ]
}||_q.|| _tƒ  	||¡ d S r    )
r   r   rW   r&   rV   rY   rZ   Úaliasr+   r   )r   r   r   rW   r2   r,   r   r   r   Ô   s    

z#Expressions.rename_table_referencesc                 C   sb   | j |krd S t| jƒ}g | _| jj |g¡D ](}|jj|krF||j_| j 	|jj¡ q.|| _d S r    )
r   r   rW   r&   rV   rY   rZ   rT   r   Úappend)r   r   r   r   rW   r2   r   r   r   r   Þ   s    

z$Expressions.rename_column_referencesc                 C   s*   | j  | j¡\}}t| j|ƒ}|t|ƒ S r    )rV   ÚcompilerW   ÚmaprX   Útuple)r   ZsqlÚparamsr   r   r   r   é   s    zExpressions.__str__)r   r   r   r"   r   r   r   r>   r   r   r,   r   rS   Ì   s   
rS   N)r   Úcopyr   r   r   r$   r)   r?   rA   rC   rH   rS   r   r   r   r   Ú<module>   s   ""&