Ajoutez des fichiers projet.

venv/Lib/site-packages/django/utils/tree.py

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+"""
+A class for storing a tree graph. Primarily used for filter constructs in the
+ORM.
+"""
+
+import copy
+
+from django.utils.hashable import make_hashable
+
+
+class Node:
+    """
+    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.
+    """
+    # Standard connector type. Clients usually won't use this at all and
+    # subclasses will usually override the value.
+    default = 'DEFAULT'
+
+    def __init__(self, children=None, connector=None, negated=False):
+        """Construct a new Node. If no connector is given, use the default."""
+        self.children = children[:] if children else []
+        self.connector = connector or self.default
+        self.negated = negated
+
+    # Required because django.db.models.query_utils.Q. Q. __init__() is
+    # problematic, but it is a natural Node subclass in all other respects.
+    @classmethod
+    def _new_instance(cls, children=None, connector=None, negated=False):
+        """
+        Create a new instance of this class when new Nodes (or subclasses) are
+        needed in the internal code in this class. Normally, it just shadows
+        __init__(). However, subclasses with an __init__ signature that aren't
+        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).
+        """
+        obj = Node(children, connector, negated)
+        obj.__class__ = cls
+        return obj
+
+    def __str__(self):
+        template = '(NOT (%s: %s))' if self.negated else '(%s: %s)'
+        return template % (self.connector, ', '.join(str(c) for c in self.children))
+
+    def __repr__(self):
+        return "<%s: %s>" % (self.__class__.__name__, self)
+
+    def __deepcopy__(self, memodict):
+        obj = Node(connector=self.connector, negated=self.negated)
+        obj.__class__ = self.__class__
+        obj.children = copy.deepcopy(self.children, memodict)
+        return obj
+
+    def __len__(self):
+        """Return the number of children this node has."""
+        return len(self.children)
+
+    def __bool__(self):
+        """Return whether or not this node has children."""
+        return bool(self.children)
+
+    def __contains__(self, other):
+        """Return True if 'other' is a direct child of this instance."""
+        return other in self.children
+
+    def __eq__(self, other):
+        return (
+            self.__class__ == other.__class__ and
+            self.connector == other.connector and
+            self.negated == other.negated and
+            self.children == other.children
+        )
+
+    def __hash__(self):
+        return hash((self.__class__, self.connector, self.negated, *make_hashable(self.children)))
+
+    def add(self, data, conn_type):
+        """
+        Combine 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.
+
+        Return a node which can be used in place of data regardless if the
+        node other got squashed or not.
+        """
+        if self.connector != conn_type:
+            obj = self._new_instance(self.children, self.connector, self.negated)
+            self.connector = conn_type
+            self.children = [obj, data]
+            return data
+        elif (
+            isinstance(data, Node) and
+            not data.negated and
+            (data.connector == conn_type or len(data) == 1)
+        ):
+            # We can squash the other node's children directly into this node.
+            # We are just doing (AB)(CD) == (ABCD) here, with the addition that
+            # if the length of the other node is 1 the connector doesn't
+            # matter. However, for the len(self) == 1 case we don't want to do
+            # the squashing, as it would alter self.connector.
+            self.children.extend(data.children)
+            return self
+        else:
+            # We could use perhaps additional logic here to see if some
+            # children could be used for pushdown here.
+            self.children.append(data)
+            return data
+
+    def negate(self):
+        """Negate the sense of the root connector."""
+        self.negated = not self.negated