Files
zulip/tools/lib/graph.py
Anders Kaseorg 5901e7ba7e python: Convert function type annotations to Python 3 style.
Generated by com2ann (slightly patched to avoid also converting
assignment type annotations, which require Python 3.6), followed by
some manual whitespace adjustment, and six fixes for runtime issues:

-    def __init__(self, token: Token, parent: Optional[Node]) -> None:
+    def __init__(self, token: Token, parent: "Optional[Node]") -> None:

-def main(options: argparse.Namespace) -> NoReturn:
+def main(options: argparse.Namespace) -> "NoReturn":

-def fetch_request(url: str, callback: Any, **kwargs: Any) -> Generator[Callable[..., Any], Any, None]:
+def fetch_request(url: str, callback: Any, **kwargs: Any) -> "Generator[Callable[..., Any], Any, None]":

-def assert_server_running(server: subprocess.Popen[bytes], log_file: Optional[str]) -> None:
+def assert_server_running(server: "subprocess.Popen[bytes]", log_file: Optional[str]) -> None:

-def server_is_up(server: subprocess.Popen[bytes], log_file: Optional[str]) -> bool:
+def server_is_up(server: "subprocess.Popen[bytes]", log_file: Optional[str]) -> bool:

-    method_kwarg_pairs: List[FuncKwargPair],
+    method_kwarg_pairs: "List[FuncKwargPair]",

Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
2020-04-18 20:42:48 -07:00

126 lines
3.7 KiB
Python

from collections import defaultdict
from typing import Callable, DefaultDict, Iterator, List, Optional, Set, Tuple
Edge = Tuple[str, str]
EdgeSet = Set[Edge]
class Graph:
def __init__(self, tuples: EdgeSet) -> None:
self.children = defaultdict(list) # type: DefaultDict[str, List[str]]
self.parents = defaultdict(list) # type: DefaultDict[str, List[str]]
self.nodes = set() # type: Set[str]
for parent, child in tuples:
self.parents[child].append(parent)
self.children[parent].append(child)
self.nodes.add(parent)
self.nodes.add(child)
def copy(self) -> 'Graph':
return Graph(self.edges())
def num_edges(self) -> int:
return len(self.edges())
def minus_edge(self, edge: Edge) -> 'Graph':
edges = self.edges().copy()
edges.remove(edge)
return Graph(edges)
def edges(self) -> EdgeSet:
s = set()
for parent in self.nodes:
for child in self.children[parent]:
s.add((parent, child))
return s
def remove_exterior_nodes(self) -> None:
still_work_to_do = True
while still_work_to_do:
still_work_to_do = False # for now
for node in self.nodes:
if self.is_exterior_node(node):
self.remove(node)
still_work_to_do = True
break
def is_exterior_node(self, node: str) -> bool:
parents = self.parents[node]
children = self.children[node]
if not parents:
return True
if not children:
return True
if len(parents) > 1 or len(children) > 1:
return False
# If our only parent and child are the same node, then we could
# effectively be collapsed into the parent, so don't add clutter.
return parents[0] == children[0]
def remove(self, node: str) -> None:
for parent in self.parents[node]:
self.children[parent].remove(node)
for child in self.children[node]:
self.parents[child].remove(node)
self.nodes.remove(node)
def report(self) -> None:
print('parents/children/module')
tups = sorted([
(len(self.parents[node]), len(self.children[node]), node)
for node in self.nodes])
for tup in tups:
print(tup)
def best_edge_to_remove(orig_graph: Graph, is_exempt: Callable[[Edge], bool]) -> Optional[Edge]:
# expects an already reduced graph as input
orig_edges = orig_graph.edges()
def get_choices() -> Iterator[Tuple[int, Edge]]:
for edge in orig_edges:
if is_exempt(edge):
continue
graph = orig_graph.minus_edge(edge)
graph.remove_exterior_nodes()
size = graph.num_edges()
yield (size, edge)
choices = list(get_choices())
if not choices:
return None
min_size, best_edge = min(choices)
if min_size >= orig_graph.num_edges():
raise Exception('no edges work here')
return best_edge
def make_dot_file(graph: Graph) -> str:
buffer = 'digraph G {\n'
for node in graph.nodes:
buffer += node + ';\n'
for child in graph.children[node]:
buffer += '{} -> {};\n'.format(node, child)
buffer += '}'
return buffer
def test() -> None:
graph = Graph({
('x', 'a'),
('a', 'b'),
('b', 'c'),
('c', 'a'),
('c', 'd'),
('d', 'e'),
('e', 'f'),
('e', 'g'),
})
graph.remove_exterior_nodes()
s = make_dot_file(graph)
open('zulip-deps.dot', 'w').write(s)
if __name__ == '__main__':
test()