fix: applied review and added test expected warning

Signed-off-by: weichslgartner <[email protected]>

Author: weichslgartner

.pre-commit-config.yaml

@@ -4,7 +4,7 @@ repos:
     hooks:
       - id: system
         name: mypy
-        entry: poetry run tox -e mypy-locked
+        entry: poetry run tox -e mypy-current
         pass_filenames: false
         language: system
   - repo: local

tests/test_model_bom.py

@@ -140,13 +140,19 @@ def test_empty_bom(self) -> None:
         self.assertFalse(bom.external_references)
 
     def test_root_component_only_bom(self) -> None:
-        with warnings.catch_warnings():
-            warnings.simplefilter('error', UserWarning)  # Turn UserWarnings into errors
-            try:
-                bom = Bom(metadata=BomMetaData(component=Component(name='test', version='1.2')))
-                _ = JsonV1Dot6(bom).output_as_string()
-            except UserWarning as e:
-                self.fail(f"A warning with 'warn' was issued: {e}")
+        with warnings.catch_warnings(record=True) as w:
+            warnings.simplefilter('always')
+            bom = Bom(metadata=BomMetaData(component=Component(name='test', version='1.2')))
+            _ = JsonV1Dot6(bom).output_as_string()
+            self.assertEqual(len(w), 0)
+
+    def test_warning_missing_dependency(self) -> None:
+        with self.assertWarns(expected_warning=UserWarning) as w:
+            bom = Bom(metadata=BomMetaData(component=Component(name='root_component', version='1.2')))
+            bom.components.add(Component(name='test2', version='4.2'))
+            _ = JsonV1Dot6(bom).output_as_string()
+            self.assertEqual(len(w.warnings), 1)
+            self.assertIn('has no defined dependencies ', str(w.warnings[0]))
 
     def test_empty_bom_defined_serial(self) -> None:
         serial_number = uuid4()