style: PR feedback

Author: yt-ms

tests/integration/test_model_element_relationships.py

@@ -86,7 +86,7 @@ def test_adding_relationship_via_uses_adds_to_elements():
     "filename",
     ["BigBank.json"],
 )
-def test_relationships_after_deserialisation_are_consistent(filename):
+def test_relationships_after_deserialisation_are_consistent(filename: str):
     """Make sure that relationships are consistent between the Model and the Element after deserialisation."""
     path = DEFINITIONS / filename
     workspace = Workspace.load(path)
@@ -100,6 +100,6 @@ def test_relationships_after_deserialisation_are_consistent(filename):
         len(list(atm.get_relationships())) == 2
     )  # One to mainframe, one from personal banking customer
     assert len(list(atm.get_afferent_relationships())) == 1
-    assert list(atm.get_afferent_relationships())[0].source is customer
+    assert next(atm.get_afferent_relationships()).source is customer
     assert len(list(atm.get_efferent_relationships())) == 1
-    assert list(atm.get_efferent_relationships())[0].destination is mainframe
+    assert next(atm.get_efferent_relationships()).destination is mainframe

tests/unit/model/test_element.py

@@ -68,10 +68,7 @@ def test_element_can_only_add_relationship_to_source():
 
 
 def test_element_add_relationship_can_omit_source():
-    """
-    When using add_relationship with params rather than an existing instance,
-    it should default the source.
-    """
+    """Expect that creating a relationship uses the default source."""
     element1 = ConcreteElement(name="elt1")
     element2 = ConcreteElement(name="elt1")
     model = MockModel()
@@ -81,9 +78,7 @@ def test_element_add_relationship_can_omit_source():
 
 
 def test_element_add_relationship_twice_is_ok():
-    """
-    Defensive test that adding the same relationship twice is fine.
-    """
+    """Ensure that adding the same relationship twice is fine."""
     element1 = ConcreteElement(name="elt1")
     element2 = ConcreteElement(name="elt1")
     model = MockModel()