def test_should_find_long_nontrivial_cycle_in_graph_when_there_are_two(
self):
graph_with_long_cycle = Graph({
"a": "b",
"b": "c",
"c": "a",
"d": "e",
"e": "f",
"f": "d"
})
self.assertIsNotNone(graph_with_long_cycle.assert_no_cycles_present())
def build_execution_plan(self, task_names):
self.assert_dependencies_resolved()
execution_plan = []
dependency_edges = {}
for task in self.collect_all_transitive_tasks(as_list(task_names)):
dependency_edges[task.name] = task.dependencies
try:
Graph(dependency_edges).assert_no_cycles_present()
except GraphHasCycles as cycles:
raise CircularTaskDependencyException(str(cycles))
for task_name in as_list(task_names):
self.enqueue_task(execution_plan, task_name)
return execution_plan
def test_should_not_find_cycles_in_graph_when_there_are_none(self):
graph_without_cycle = Graph({"a": "b", "b": "c", "d": "e"})
graph_without_cycle.assert_no_cycles_present()
def test_should_find_simple_nontrivial_cycle_in_graph_when_there_is_one(
self):
graph_with_simple_cycle = Graph({"a": "b", "b": "a"})
self.assertIsNotNone(
graph_with_simple_cycle.assert_no_cycles_present())
def test_should_find_trivial_cycle_in_graph_when_there_are_two(self):
graph_with_trivial_cycles = Graph({"a": "a", "b": "b"})
self.assertIsNotNone(
graph_with_trivial_cycles.assert_no_trivial_cycles_present())
def test_should_find_trivial_cycle_in_graph_when_searching_for_cycles(
self):
graph_with_trivial_cycle = Graph({"a": "a"})
self.assertIsNotNone(
graph_with_trivial_cycle.assert_no_cycles_present())
def test_should_not_find_cycles_in_graph_when_there_are_none(self):
graph_without_cycle = Graph({"a": "b", "b": "c", "d": "e"})
graph_without_cycle.assert_no_cycles_present()
def test_should_find_long_nontrivial_cycle_in_graph_when_there_is_one(
self):
graph_with_long_cycle = Graph({"a": "b", "b": "c", "c": "d", "d": "b"})
self.assertRaises(GraphHasCycles,
graph_with_long_cycle.assert_no_cycles_present)
def test_should_find_trivial_cycle_in_graph_when_searching_for_cycles(
self):
graph_with_trivial_cycle = Graph({"a": "a"})
self.assertRaises(GraphHasCycles,
graph_with_trivial_cycle.assert_no_cycles_present)
def test_should_find_trivial_cycle_in_graph_when_there_are_two(self):
graph_with_trivial_cycles = Graph({"a": "a", "b": "b"})
self.assertRaises(
GraphHasCycles,
graph_with_trivial_cycles.assert_no_trivial_cycles_present)
def test_should_find_trivial_cycle_in_graph_when_there_is_one(self):
graph_with_trivial_cycle = Graph({"a": "a"})
self.assertRaises(
GraphHasCycles,
graph_with_trivial_cycle.assert_no_trivial_cycles_present)