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-rw-r--r--lib/git/async/graph.py126
1 files changed, 0 insertions, 126 deletions
diff --git a/lib/git/async/graph.py b/lib/git/async/graph.py
deleted file mode 100644
index 4e14c81e..00000000
--- a/lib/git/async/graph.py
+++ /dev/null
@@ -1,126 +0,0 @@
-"""Simplistic implementation of a graph"""
-
-__all__ = ('Node', 'Graph')
-
-class Node(object):
- """A Node in the graph. They know their neighbours, and have an id which should
- resolve into a string"""
- __slots__ = ('in_nodes', 'out_nodes', 'id')
-
- def __init__(self, id=None):
- self.id = id
- self.in_nodes = list()
- self.out_nodes = list()
-
- def __str__(self):
- return str(self.id)
-
- def __repr__(self):
- return "%s(%s)" % (type(self).__name__, self.id)
-
-
-class Graph(object):
- """A simple graph implementation, keeping nodes and providing basic access and
- editing functions. The performance is only suitable for small graphs of not
- more than 10 nodes !"""
- __slots__ = "nodes"
-
- def __init__(self):
- self.nodes = list()
-
- def __del__(self):
- """Deletes bidericational dependencies"""
- for node in self.nodes:
- node.in_nodes = None
- node.out_nodes = None
- # END cleanup nodes
-
- # otherwise the nodes would keep floating around
-
-
- def add_node(self, node):
- """Add a new node to the graph
- :return: the newly added node"""
- self.nodes.append(node)
- return node
-
- def remove_node(self, node):
- """Delete a node from the graph
- :return: self"""
- try:
- del(self.nodes[self.nodes.index(node)])
- except ValueError:
- return self
- # END ignore if it doesn't exist
-
- # clear connections
- for outn in node.out_nodes:
- del(outn.in_nodes[outn.in_nodes.index(node)])
- for inn in node.in_nodes:
- del(inn.out_nodes[inn.out_nodes.index(node)])
- node.out_nodes = list()
- node.in_nodes = list()
- return self
-
- def add_edge(self, u, v):
- """Add an undirected edge between the given nodes u and v.
-
- return: self
- :raise ValueError: If the new edge would create a cycle"""
- if u is v:
- raise ValueError("Cannot connect a node with itself")
-
- # are they already connected ?
- if u in v.in_nodes and v in u.out_nodes or \
- v in u.in_nodes and u in v.out_nodes:
- return self
- # END handle connection exists
-
- # cycle check - if we can reach any of the two by following either ones
- # history, its a cycle
- for start, end in ((u, v), (v,u)):
- if not start.in_nodes:
- continue
- nodes = start.in_nodes[:]
- seen = set()
- # depth first search - its faster
- while nodes:
- n = nodes.pop()
- if n in seen:
- continue
- seen.add(n)
- if n is end:
- raise ValueError("Connecting u with v would create a cycle")
- nodes.extend(n.in_nodes)
- # END while we are searching
- # END for each direction to look
-
- # connection is valid, set it up
- u.out_nodes.append(v)
- v.in_nodes.append(u)
-
- return self
-
- def input_inclusive_dfirst_reversed(self, node):
- """Return all input nodes of the given node, depth first,
- It will return the actual input node last, as it is required
- like that by the pool"""
- stack = [node]
- seen = set()
-
- # depth first
- out = list()
- while stack:
- n = stack.pop()
- if n in seen:
- continue
- seen.add(n)
- out.append(n)
-
- # only proceed in that direction if visitor is fine with it
- stack.extend(n.in_nodes)
- # END call visitor
- # END while walking
- out.reverse()
- return out
-