B
    CVvgó  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-install-o3oxmrkh/Django/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NotImplementedError)r   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 )N)r   )r   r   r   r   r   r   1   s    zTable.references_tablec             C   s   | j |kr|| _ d S )N)r   )r   r   r   r   r   r   r   4   s    
zTable.rename_table_referencesc             C   s   |   | j¡S )N)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 )N)r   Úcolumns)r   r   r   r   r   r   r   ?   s    zTableColumns.__init__c             C   s   | j |ko|| jkS )N)r   r   )r   r   r	   r   r   r   r
   C   s    zTableColumns.references_columnc             C   s8   | j |kr4x(t| jƒD ]\}}||kr|| j|< qW d S )N)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 )N)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   | ¡}yˆ j| }|r&d ||¡}W n tk
r<   Y nX |S )Nz{} {})r   r"   ÚformatÚ
IndexError)r	   ÚidxÚcolÚsuffix)r   r   r   Úcol_strV   s    

z Columns.__str__.<locals>.col_strz, c             3   s   | ]\}}ˆ ||ƒV  qd S )Nr   )Ú.0r&   r	   )r)   r   r   ú	<genexpr>`   s    z"Columns.__str__.<locals>.<genexpr>)Újoinr   r   )r   r   )r)   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 )N)r(   Úcreate_index_namer#   r   )r   r   r   r(   r/   )r   r   r   r   f   s    zIndexName.__init__c             C   s   |   | j| j| j¡S )N)r/   r   r   r(   )r   r   r   r   r   k   s    zIndexName.__str__)r   r   r   r   r   r   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 )N)Ú	opclassesr#   r   )r   r   r   r   r"   r1   )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| ¡}yˆ j| }|r4d  ||¡}W n tk
rJ   Y nX |S )Nz{} {})r$   r   r1   r"   r%   )r	   r&   r'   r(   )r   r   r   r)   u   s    
z%IndexColumns.__str__.<locals>.col_strz, c             3   s   | ]\}}ˆ ||ƒV  qd S )Nr   )r*   r&   r	   )r)   r   r   r+   �   s    z'IndexColumns.__str__.<locals>.<genexpr>)r,   r   r   )r   r   )r)   r   r   r   t   s    zIndexColumns.__str__)r   r   )r   r   r   r   r   r-   r   r   )r   r   r0   o   s   r0   c                   sX   e Zd ZdZ‡ fdd„Z‡ fdd„Z‡ fdd„Z‡ fdd	„Z‡ fd
d„Zdd„ Z	‡  Z
S )ÚForeignKeyNamez'Hold a reference to a foreign key name.c                s*   t ||ƒ| _|| _|| _tƒ  ||¡ d S )N)r   Úto_referenceÚsuffix_templateÚcreate_fk_namer#   r   )r   Z
from_tableZfrom_columnsÚto_tableZ
to_columnsr4   r5   )r   r   r   r   ‡   s    zForeignKeyName.__init__c                s   t ƒ  |¡p| j |¡S )N)r#   r   r3   )r   r   )r   r   r   r   �   s    zForeignKeyName.references_tablec                s   t ƒ  ||¡p| j ||¡S )N)r#   r
   r3   )r   r   r	   )r   r   r   r
   �   s    z ForeignKeyName.references_columnc                s    t ƒ  ||¡ | j ||¡ d S )N)r#   r   r3   )r   r   r   )r   r   r   r   –   s    z&ForeignKeyName.rename_table_referencesc                s$   t ƒ  |||¡ | j |||¡ d S )N)r#   r   r3   )r   r   r   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   )r6   Z	to_column)r4   r3   r   r   r5   )r   r(   r   r   r   r   ž   s    zForeignKeyName.__str__)r   r   r   r   r   r   r
   r   r   r   r-   r   r   )r   r   r2   „   s   r2   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 )N)ÚtemplateÚparts)r   r8   r9   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   )r*   Úpart)r   r   r   r+   ´   s   z-Statement.references_table.<locals>.<genexpr>)Úanyr9   Úvalues)r   r   r   )r   r   r   ²   s    
zStatement.references_tablec                s   t ‡ ‡fdd„| j ¡ D ƒƒS )Nc             3   s$   | ]}t |d ƒo| ˆˆ ¡V  qdS )r
   N)r:   r
   )r*   r;   )r	   r   r   r   r+   º   s   z.Statement.references_column.<locals>.<genexpr>)r<   r9   r=   )r   r   r	   r   )r	   r   r   r
   ¸   s    zStatement.references_columnc             C   s.   x(| j  ¡ D ]}t|dƒr| ||¡ qW d S )Nr   )r9   r=   r:   r   )r   r   r   r;   r   r   r   r   ¾   s    
z!Statement.rename_table_referencesc             C   s0   x*| j  ¡ D ]}t|dƒr| |||¡ qW d S )Nr   )r9   r=   r:   r   )r   r   r   r   r;   r   r   r   r   Ã   s    
z"Statement.rename_column_referencesc             C   s   | j | j S )N)r8   r9   )r   r   r   r   r   È   s    zStatement.__str__N)
r   r   r   r   r   r   r
   r   r   r   r   r   r   r   r7   ¦   s   r7   c                   s8   e Zd Z‡ fdd„Z‡ fdd„Zdd„ Zdd„ Z‡  ZS )	ÚExpressionsc                s@   || _ || _|| _dd„ | j j | jg¡D ƒ}tƒ  ||¡ d S )Nc             S   s   g | ]}|j j‘qS r   )Útargetr	   )r*   r'   r   r   r   ú
<listcomp>Ñ   s    z(Expressions.__init__.<locals>.<listcomp>)ÚcompilerÚexpressionsÚquote_valueÚqueryÚ	_gen_colsr#   r   )r   r   rB   rA   rC   r   )r   r   r   r   Í   s
    zExpressions.__init__c                s2   | j |krd S | j ||i¡| _tƒ  ||¡ d S )N)r   rB   Zrelabeled_cloner#   r   )r   r   r   )r   r   r   r   Ô   s    
z#Expressions.rename_table_referencesc             C   sf   | j |krd S t| jƒ}g | _x<| jj |g¡D ](}|jj|krH||j_| j 	|jj¡ q0W || _d S )N)
r   r   rB   r   rA   rD   rE   r?   r	   Úappend)r   r   r   r   rB   r'   r   r   r   r   Ú   s    

z$Expressions.rename_column_referencesc             C   s*   | j  | j¡\}}t| j|ƒ}|t|ƒ S )N)rA   ÚcompilerB   ÚmaprC   Útuple)r   ZsqlÚparamsr   r   r   r   å   s    zExpressions.__str__)r   r   r   r   r   r   r   r-   r   r   )r   r   r>   Ì   s   r>   N)r   Úcopyr   r   r   r   r!   r.   r0   r2   r7   r>   r   r   r   r   Ú<module>   s   ""&