def start_with_graph():
global dag
dag = DAG()
dag.from_dict({'a': ['b', 'c'],
'b': ['d'],
'c': ['d'],
'd': []})
def start_with_graph():
global dag
dag = DAG()
dag.from_dict({'a': ['b', 'c'],
'b': ['d'],
'c': ['d'],
'd': []})
def basic_dag():
dag = DAG()
dag.from_dict({'a': ['b', 'c'],
'b': ['d'],
'c': ['d'],
'd': []})
return dag
def test_all_downstreams_pass_graph():
dag2 = DAG()
dag2.from_dict({'a': ['c'],
'b': ['d'],
'c': ['d'],
'd': []})
assert dag2.all_downstreams('a') == ['c', 'd']
assert dag2.all_downstreams('b') == ['d']
assert dag2.all_downstreams('d') == []
def test_all_downstreams_pass_graph():
dag2 = DAG()
dag2.from_dict({'a': ['c'],
'b': ['d'],
'c': ['d'],
'd': []})
assert dag2.all_downstreams('a') == ['c', 'd']
assert dag2.all_downstreams('b') == ['d']
assert dag2.all_downstreams('d') == []
def test_transitive_reduction_no_reduction():
dag = DAG()
dag.from_dict({'a': ['b', 'c'], 'b': ['d'], 'c': ['d'], 'd': []})
dag.transitive_reduction()
assert dag.graph == {
'a': set(['b', 'c']),
'b': set('d'),
'c': set('d'),
'd': set()
}
def test_transitive_reduction_no_reduction():
dag = DAG()
dag.from_dict({'a': ['b', 'c'],
'b': ['d'],
'c': ['d'],
'd': []})
dag.transitive_reduction()
assert dag.graph == {'a': set(['b', 'c']),
'b': set('d'),
'c': set('d'),
'd': set()}
def test_walk():
dag = DAG()
# b and c should be executed at the same time.
dag.from_dict({'a': ['b', 'c'], 'b': ['d'], 'c': ['d'], 'd': []})
nodes = []
def walk_func(n):
nodes.append(n)
return True
dag.walk(walk_func)
assert nodes == ['d', 'c', 'b', 'a'] or nodes == ['d', 'b', 'c', 'a']
def test_transitive_deep_reduction():
dag = DAG()
# https://en.wikipedia.org/wiki/Transitive_reduction#/media/File:Tred-G.svg
dag.from_dict({
'a': ['b', 'd'],
'b': ['c'],
'c': ['d'],
'd': [],
})
dag.transitive_reduction()
# https://en.wikipedia.org/wiki/Transitive_reduction#/media/File:Tred-Gprime.svg
assert dag.graph == {'a': set('b'),
'b': set('c'),
'c': set('d'),
'd': set()}
def test_walk():
dag = DAG()
# b and c should be executed at the same time.
dag.from_dict({'a': ['b', 'c'],
'b': ['d'],
'c': ['d'],
'd': []})
nodes = []
def walk_func(n):
nodes.append(n)
return True
dag.walk(walk_func)
assert nodes == ['d', 'c', 'b', 'a'] or nodes == ['d', 'b', 'c', 'a']
def test_threaded_walker():
dag = DAG()
walker = ThreadedWalker()
# b and c should be executed at the same time.
dag.from_dict({'a': ['b', 'c'], 'b': ['d'], 'c': ['d'], 'd': []})
lock = threading.Lock() # Protects nodes from concurrent access
nodes = []
def walk_func(n):
lock.acquire()
nodes.append(n)
lock.release()
return True
walker.walk(dag, walk_func)
assert nodes == ['d', 'c', 'b', 'a'] or nodes == ['d', 'b', 'c', 'a']
def test_walk_failed():
dag = DAG()
# b and c should be executed at the same time.
dag.from_dict({'a': ['b', 'c'],
'b': ['d'],
'c': ['d'],
'd': []})
nodes = []
def walk_func(n):
nodes.append(n)
return False
ok = dag.walk(walk_func)
# Only 2 should have been hit. The rest are canceled because they depend on
# the success of d.
assert ok == False # noqa: E712
assert nodes == ['d', 'c', 'b', 'a'] or nodes == ['d', 'b', 'c', 'a']
def test_threaded_walker():
dag = DAG()
walker = ThreadedWalker()
# b and c should be executed at the same time.
dag.from_dict({'a': ['b', 'c'],
'b': ['d'],
'c': ['d'],
'd': []})
lock = threading.Lock() # Protects nodes from concurrent access
nodes = []
def walk_func(n):
lock.acquire()
nodes.append(n)
lock.release()
return True
walker.walk(dag, walk_func)
assert nodes == ['d', 'c', 'b', 'a'] or nodes == ['d', 'b', 'c', 'a']
def basic_dag():
dag = DAG()
dag.from_dict({'a': ['b', 'c'], 'b': ['d'], 'c': ['d'], 'd': []})
return dag
