_V@s,dZddlZGdddeZdS)zT A class for storing a tree graph. Primarily used for filter constructs in the ORM. Nc@seZdZdZdZdddddZedddddZd d Zd d Z d dZ ddZ ddZ ddZ ddZdddZddZdS)Nodez A single internal node in the tree graph. A Node should be viewed as a connection (the root) with the children being either leaf nodes or other Node instances. DEFAULTNFcCs>|r|ddng|_|p+|j|_||_dS)zd Constructs a new Node. If no connector is given, the default will be used. N)childrendefault connectornegated)selfrrrr 3/tmp/pip-build-ghmbqnp_/Django/django/utils/tree.py__init__sz Node.__init__cCst|||}||_|S)a This is called to create a new instance of this class when we need new Nodes (or subclasses) in the internal code in this class. Normally, it just shadows __init__(). However, subclasses with an __init__ signature that is not an extension of Node.__init__ might need to implement this method to allow a Node to create a new instance of them (if they have any extra setting up to do). )r __class__)clsrrrobjr r r _new_instances  zNode._new_instancecCs]|jr3d|jdjdd|jDfSd|jdjdd|jDfS)Nz(NOT (%s: %s))z, css|]}t|VqdS)N)str).0cr r r .szNode.__str__..z(%s: %s)css|]}t|VqdS)N)r)rrr r r r0s)rrjoinr)rr r r __str__,s  z Node.__str__cCsd|jj|fS)Nz<%s: %s>)r __name__)rr r r __repr__3sz Node.__repr__cCsCtd|jd|j}|j|_tj|j||_|S)z9 Utility method used by copy.deepcopy(). rr)rrrr copydeepcopyr)rZmemodictrr r r __deepcopy__6s zNode.__deepcopy__cCs t|jS)zF The size of a node if the number of children it has. )lenr)rr r r __len__?sz Node.__len__cCs t|jS)z* For truth value testing. )boolr)rr r r __bool__Esz Node.__bool__cCst|j|S)N)typer)rr r r __nonzero__KszNode.__nonzero__cCs ||jkS)zM Returns True is 'other' is a direct child of this instance. )r)rotherr r r __contains__NszNode.__contains__TcCs||jkr|S|s-|jj||S|j|krt|tr|j r|j|ksvt|dkr|jj|j|S|jj||Sn:|j|j|j|j}||_||g|_|SdS)a> Combines this tree and the data represented by data using the connector conn_type. The combine is done by squashing the node other away if possible. This tree (self) will never be pushed to a child node of the combined tree, nor will the connector or negated properties change. The function returns a node which can be used in place of data regardless if the node other got squashed or not. If `squash` is False the data is prepared and added as a child to this tree without further logic. N) rappendr isinstancerrrextendr)rdataZ conn_typeZsquashrr r r addTs"!  zNode.addcCs|j |_dS)z9 Negate the sense of the root connector. N)r)rr r r negatesz Node.negate)r __module__ __qualname____doc__rr classmethodrrrrrrr r"r(r)r r r r r s        ,r)r,robjectrr r r r s