parameter first attempt

mytest/byron/classes/parameter-test.py

@@ -0,0 +1,57 @@
+import pytest
+from byron.classes.parameter import ParameterStructuralABC, NodeReference
+import networkx as nx
+
+
+@pytest.fixture
+def simple_graph():
+    G = nx.MultiDiGraph()
+    G.add_node(1)
+    G.add_node(2)
+    return G
+
+@pytest.fixture
+def node_reference(simple_graph):
+    return NodeReference(simple_graph, 1)
+
+class TestParameterStructuralABC:
+
+    def test_init(self):
+        param = ParameterStructuralABC()
+        assert param._node_reference is None
+
+    def test_fasten(self, node_reference):
+        param = ParameterStructuralABC()
+        param.fasten(node_reference)
+        assert param._node_reference == node_reference
+
+    def test_unfasten(self, node_reference):
+        param = ParameterStructuralABC()
+        param.fasten(node_reference)
+        param.unfasten()
+        assert param._node_reference is None
+
+    def test_is_fastened(self, node_reference):
+        param = ParameterStructuralABC()
+        assert not param.is_fastened
+        param.fasten(node_reference)
+        assert param.is_fastened
+
+    def test_value_getter_fastened(self, node_reference, simple_graph):
+        param = ParameterStructuralABC()
+        param.fasten(node_reference)
+        simple_graph.add_edge(1, 2, key=param.key, _type='LINK')
+        assert param.value == 2
+
+    def test_value_getter_unfastened(self):
+        param = ParameterStructuralABC()
+        with pytest.raises(AssertionError):
+            _ = param.value
+
+    def test_value_setter(self, node_reference, simple_graph):
+        param = ParameterStructuralABC()
+        param.fasten(node_reference)
+        param.value = 2
+        assert param.value == 2
+        assert (1, 2, param.key) in simple_graph.edges(keys=True)
+