def test_bad_node_select(self, dim):
"""Tests if function raises a ``ValueError`` when input an invalid ``node_select``
argument"""
graph = nx.barbell_graph(dim, 0)
s = [0]
with pytest.raises(ValueError, match="Node selection method not recognized"):
clique.grow(s, graph, node_select="")
def test_grow_maximal(self, dim):
"""Test if function grows to expected maximal graph and then stops. The chosen graph is
composed of two fully connected graphs joined together at one node. Starting from the
first node, ``grow`` is expected to grow to be the first fully connected graph."""
graph = nx.barbell_graph(dim, 0)
s = [0]
assert set(clique.grow(s, graph)) == set(range(dim))
def test_grow_maximal_degree(self, dim):
"""Test if function grows to expected maximal graph when degree-based node selection is
used. The chosen graph is a fully connected graph with only the final node being
connected to an additional node. Furthermore, the ``dim - 2`` node is disconnected from
the ``dim - 1`` node. Starting from the first ``dim - 3`` nodes, one can either add in
the ``dim - 2`` node or the ``dim - 1`` node. The ``dim - 1`` node has a higher degree
due to the lollipop graph structure, and hence should be selected."""
graph = nx.lollipop_graph(dim, 1)
graph.remove_edge(dim - 2, dim - 1)
s = set(range(dim - 2))
target = s | {dim - 1}
assert set(clique.grow(s, graph, node_select="degree")) == target
def test_grow_maximal_degree_tie(self, dim, monkeypatch):
"""Test if function grows using randomness to break ties during degree-based node
selection. The chosen graph is a fully connected graph with the ``dim - 2`` and ``dim -
1`` nodes then disconnected. Starting from the first ``dim - 3`` nodes, one can add
either of the ``dim - 2`` and ``dim - 1`` nodes. As they have the same degree, they should
be selected randomly with equal probability. This function monkeypatches the
``np.random.choice`` call to guarantee that one of the nodes is picked during one run of
``grow`` and the other node is picked during the next run."""
graph = nx.complete_graph(dim)
graph.remove_edge(dim - 2, dim - 1)
s = set(range(dim - 2))
patch_random_choice_1 = functools.partial(patch_random_choice, element=0)
patch_random_choice_2 = functools.partial(patch_random_choice, element=1)
with monkeypatch.context() as m:
m.setattr(np.random, "choice", patch_random_choice_1)
c1 = clique.grow(s, graph, node_select="degree")
with monkeypatch.context() as m:
m.setattr(np.random, "choice", patch_random_choice_2)
c2 = clique.grow(s, graph, node_select="degree")
assert c1 != c2
def test_input_not_subgraph(self, dim):
"""Test if function raises a ``ValueError`` when input is not a subgraph"""
with pytest.raises(ValueError, match="Input is not a valid subgraph"):
clique.grow([dim + 1], nx.empty_graph(dim))
def test_input_not_clique(self, dim):
"""Tests if function raises a ``ValueError`` when input is not a clique"""
with pytest.raises(ValueError, match="Input subgraph is not a clique"):
clique.grow([0, 1], nx.empty_graph(dim))