def test_construction():
dag = DAG()
dag\
.add_vertex(0)\
.add_vertex(1)\
.add_vertex(2)
assert not dag.adjacent(0)
dag\
.add_edge(0, 2)\
.add_edge(0, 1)
assert dag.adjacent(0) == {1, 2}
assert not dag.adjacent(2)
assert not dag.adjacent(1)
dag.add_vertex(0)
assert dag.adjacent(0) == {1, 2}
dag\
.add_edge(3, 0)\
.add_edge(3, 2)\
.add_edge(2, 3)\
.add_edge(3, 4)
assert dag.adjacent(3) == {0, 2, 4}
assert dag.adjacent(2) == {3}
assert dag.adjacent(4) == set()
def test_equality():
dag_a = DAG()
dag_a[2] = [0, 1]
dag_a[0] = [2]
dag_b = DAG()
dag_b[0] = [2]
dag_b[2] = [1, 0]
assert dag_a == dag_b
assert dag_b == dag_a
dag_a[0].add(1)
assert dag_a != dag_b
assert dag_b != dag_a
def test_str():
dag = DAG()
dag[0] = [1]
dag[1] = [0]
assert str(dag) == '{0: {1}, 1: {0}}' or str(dag) == '{1: {0}, 0: {1}}'
assert repr(dag) == 'DAG({0: {1}, 1: {0}})' or repr(
dag) == 'DAG({1: {0}, 0: {1}})'
def test_path():
dag = DAG()
dag[0] = [1, 2, 3]
dag[1] = [4, 5]
dag[3] = [5, 6]
assert dag.paths(0, 2) == {(0, 2)}
assert not dag.paths(2, 0)
assert dag.paths(0, 0) == {(0, )}
assert dag.paths(0, 6) == {(0, 3, 6)}
assert dag.paths(1, 5) == {(1, 5)}
assert dag.paths(0, 5) == {(0, 1, 5), (0, 3, 5)}
with pytest.raises(KeyError, match='.* is not in this graph'):
dag.paths(0, 7)
with pytest.raises(KeyError, match='.* is not in this graph'):
dag.paths(8, 7)
def test_sub_super():
dag_a = DAG()
dag_a[2] = [0, 1]
dag_a[0] = [2]
dag_b = DAG()
dag_b[0] = [2]
dag_b[2] = [1, 0]
dag_c = DAG()
dag_c[0] = [2]
dag_c[2] = [0]
assert dag_a.is_subgraph(dag_b)
assert dag_a <= dag_b
assert dag_a.is_supergraph(dag_b)
assert dag_a >= dag_b
assert dag_c <= dag_a
assert dag_c <= dag_b
assert dag_a >= dag_c
assert not dag_c >= dag_a
assert dag_b >= dag_c
assert not dag_c >= dag_b
# For coverage...
with pytest.raises(TypeError, match='not a graph'):
dag_a.is_subgraph('blah')
with pytest.raises(TypeError, match='not a graph'):
dag_a.is_supergraph('blah')
assert dag_a != 'blah'
with pytest.raises(TypeError, match="'<=' not supported.*"):
dag_a <= 'blah'
with pytest.raises(TypeError, match="'>=' not supported.*"):
dag_a >= 'blah'
def test_contents():
dag = DAG()
dag\
.add_edge(0, 1)\
.add_edge(1, 0)\
.add_edge(2, 1)
assert dag.contains_vertex(0)
assert dag.contains_vertex(2)
assert dag.contains_vertex(1)
assert not dag.contains_vertex(5)
assert dag.contains_edge(0, 1)
assert dag.contains_edge(2, 1)
assert dag.contains_edge(1, 0)
assert not dag.contains_edge(1, 2)
assert not dag.contains_edge(5, 6)
def test_operator_contents():
dag = DAG()
dag[0] = [1]
dag[1] = [0]
dag[2] = [1]
assert 0 in dag
assert 2 in dag
assert 1 in dag
assert 5 not in dag
assert (0, 1) in dag
assert (2, 1) in dag
assert (1, 0) in dag
assert (1, 2) not in dag
assert (5, 6) not in dag
def test_operator_deletion():
dag = DAG()
dag[0] = [1]
dag[1] = [0]
dag[2] = [1]
del dag[(0, 1)]
assert (0, 1) not in dag
with pytest.raises(KeyError):
del dag[(0, 1)]
del dag[1]
assert 1 not in dag
with pytest.raises(KeyError):
del dag[1]
assert (2, 1) not in dag
def test_operator_construction():
dag = DAG()
dag[0] = [2, 1]
dag[3] = [0, 2, 3, 4]
dag[5] = []
assert dag.adjacent(0) == {1, 2}
assert dag.adjacent(1) == set()
assert dag.adjacent(2) == set()
assert dag.adjacent(3) == {4, 3, 2, 0}
assert dag.adjacent(5) == set()
dag[0] = [4, 5]
assert dag.adjacent(0) == {4, 5}
assert dag.adjacent(3) == {4, 3, 2, 0}
def test_lca():
dag = DAG()
dag[0] = [1, 2, 3, 10]
dag[1] = [4, 5]
dag[3] = [5, 6]
dag[7] = []
dag[4] = [8]
dag[5] = [9]
dag[10] = [6, 5]
# Basic tests
assert dag.lca(0, 0, 0) == 0
assert dag.lca(1, 1, 1) == 1
assert dag.lca(0, 5, 5) == 5
assert dag.lca(0, 1, 2) == 0
assert dag.lca(0, 1, 3) == 0
assert dag.lca(0, 2, 3) == 0
assert dag.lca(1, 4, 5) == 1
# Differing heights
assert dag.lca(0, 4, 2) == 0
assert dag.lca(0, 8, 5) == 1
# Multiple paths
assert dag.lca(0, 5, 6) in (3, 10)
del dag[(10, 6)]
assert dag.lca(0, 5, 6) == 3
dag[10].add(6)
del dag[(3, 5)]
assert dag.lca(0, 5, 6) == 10
# No common ancestors
assert dag.lca(0, 1, 7) is None
def test_deletion():
dag = DAG()
dag\
.add_edge(0, 1)\
.add_edge(1, 0)\
.add_edge(2, 1)
dag.remove_edge(0, 1)
assert not dag.contains_edge(0, 1)
assert dag.adjacent(0) == set()
assert dag.contains_edge(1, 0)
assert dag.contains_vertex(0)
with pytest.raises(KeyError):
dag.remove_edge(0, 1)
dag.remove_vertex(1)
assert not dag.contains_vertex(1)
assert not dag.contains_edge(1, 0)
assert not dag.contains_edge(2, 1)
assert dag.adjacent(2) == set()
assert dag.contains_vertex(2)
with pytest.raises(KeyError):
dag.adjacent(1)