refactor: reuse internal helper bom_ref_from_str (#727)

fixes #722

Signed-off-by: Jan Kowalleck <jan.kowalleck@gmail.com>

cyclonedx/_internal/bom_ref.py

@@ -21,13 +21,31 @@
 Everything might change without any notice.
 """
 
-from typing import Optional, Union
+from typing import Literal, Optional, Union, overload
 
 from ..model.bom_ref import BomRef
 
 
-def bom_ref_from_str(bom_ref: Optional[Union[str, BomRef]]) -> BomRef:
+@overload
+def bom_ref_from_str(bom_ref: BomRef, optional: bool = ...) -> BomRef:
+    ...  # pragma: no cover
+
+
+@overload
+def bom_ref_from_str(bom_ref: Optional[str], optional: Literal[False] = False) -> BomRef:
+    ...  # pragma: no cover
+
+
+@overload
+def bom_ref_from_str(bom_ref: Optional[str], optional: Literal[True] = ...) -> Optional[BomRef]:
+    ...  # pragma: no cover
+
+
+def bom_ref_from_str(bom_ref: Optional[Union[str, BomRef]], optional: bool = False) -> Optional[BomRef]:
     if isinstance(bom_ref, BomRef):
         return bom_ref
-    else:
-        return BomRef(value=str(bom_ref) if bom_ref else None)
+    if bom_ref:
+        return BomRef(value=str(bom_ref))
+    return None \
+        if optional \
+        else BomRef()

cyclonedx/model/component.py

@@ -26,6 +26,7 @@
 from packageurl import PackageURL
 from sortedcontainers import SortedSet
 
+from .._internal.bom_ref import bom_ref_from_str as _bom_ref_from_str
 from .._internal.compare import ComparablePackageURL as _ComparablePackageURL, ComparableTuple as _ComparableTuple
 from .._internal.hash import file_sha1sum as _file_sha1sum
 from ..exception.model import InvalidOmniBorIdException, InvalidSwhidException, NoPropertiesProvidedException
@@ -1097,10 +1098,7 @@ def __init__(
     ) -> None:
         self.type = type
         self.mime_type = mime_type
-        if isinstance(bom_ref, BomRef):
-            self._bom_ref = bom_ref
-        else:
-            self._bom_ref = BomRef(value=str(bom_ref) if bom_ref else None)
+        self._bom_ref = _bom_ref_from_str(bom_ref)
         self.supplier = supplier
         self.manufacturer = manufacturer
         self.authors = authors or []  # type:ignore[assignment]

cyclonedx/model/contact.py

@@ -21,6 +21,7 @@
 import serializable
 from sortedcontainers import SortedSet
 
+from .._internal.bom_ref import bom_ref_from_str as _bom_ref_from_str
 from .._internal.compare import ComparableTuple as _ComparableTuple
 from ..exception.model import NoPropertiesProvidedException
 from ..schema.schema import SchemaVersion1Dot6
@@ -49,8 +50,7 @@ def __init__(
         postal_code: Optional[str] = None,
         street_address: Optional[str] = None,
     ) -> None:
-        self._bom_ref = bom_ref if isinstance(bom_ref, BomRef) else BomRef(
-            value=bom_ref) if bom_ref else None
+        self._bom_ref = _bom_ref_from_str(bom_ref, optional=True)
         self.country = country
         self.region = region
         self.locality = locality

cyclonedx/model/service.py

@@ -31,6 +31,7 @@
 
 from cyclonedx.serialization import BomRefHelper, LicenseRepositoryHelper
 
+from .._internal.bom_ref import bom_ref_from_str as _bom_ref_from_str
 from .._internal.compare import ComparableTuple as _ComparableTuple
 from ..schema.schema import SchemaVersion1Dot3, SchemaVersion1Dot4, SchemaVersion1Dot5, SchemaVersion1Dot6
 from . import DataClassification, ExternalReference, Property, XsUri
@@ -68,10 +69,7 @@ def __init__(
         services: Optional[Iterable['Service']] = None,
         release_notes: Optional[ReleaseNotes] = None,
     ) -> None:
-        if isinstance(bom_ref, BomRef):
-            self._bom_ref = bom_ref
-        else:
-            self._bom_ref = BomRef(value=str(bom_ref) if bom_ref else None)
+        self._bom_ref = _bom_ref_from_str(bom_ref)
         self.provider = provider
         self.group = group
         self.name = name

cyclonedx/model/vulnerability.py

@@ -38,6 +38,7 @@
 import serializable
 from sortedcontainers import SortedSet
 
+from .._internal.bom_ref import bom_ref_from_str as _bom_ref_from_str
 from .._internal.compare import ComparableTuple as _ComparableTuple
 from ..exception.model import MutuallyExclusivePropertiesException, NoPropertiesProvidedException
 from ..schema.schema import SchemaVersion1Dot4, SchemaVersion1Dot5, SchemaVersion1Dot6
@@ -959,10 +960,7 @@ def __init__(
         affects: Optional[Iterable[BomTarget]] = None,
         properties: Optional[Iterable[Property]] = None,
     ) -> None:
-        if isinstance(bom_ref, BomRef):
-            self._bom_ref: BomRef = bom_ref
-        else:
-            self._bom_ref = BomRef(value=str(bom_ref) if bom_ref else None)
+        self._bom_ref = _bom_ref_from_str(bom_ref)
         self.id = id
         self.source = source
         self.references = references or []  # type:ignore[assignment]

tests/test_internal/__init__.py

@@ -0,0 +1,16 @@
+# This file is part of CycloneDX Python Library
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (c) OWASP Foundation. All Rights Reserved.

tests/test_internal/test_bom_ref.py

@@ -0,0 +1,57 @@
+# This file is part of CycloneDX Python Library
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+# Copyright (c) OWASP Foundation. All Rights Reserved.
+
+from unittest import TestCase
+
+from cyclonedx._internal.bom_ref import bom_ref_from_str
+from cyclonedx.model.bom_ref import BomRef
+
+
+class TestInternalBomRefFromStr(TestCase):
+
+    def test_bomref_io(self) -> None:
+        i = BomRef()
+        o = bom_ref_from_str(i)
+        self.assertIs(i, o)
+
+    def test_none_optional_is_none(self) -> None:
+        o = bom_ref_from_str(None, optional=True)
+        self.assertIsNone(o)
+
+    def test_none_mandatory_is_something(self) -> None:
+        o = bom_ref_from_str(None, optional=False)
+        self.assertIsInstance(o, BomRef)
+        self.assertIsNone(o.value)
+
+    def test_nothing_optional_is_none(self) -> None:
+        o = bom_ref_from_str('', optional=True)
+        self.assertIsNone(o)
+
+    def test_nothing_mandatory_is_something(self) -> None:
+        o = bom_ref_from_str('', optional=False)
+        self.assertIsInstance(o, BomRef)
+        self.assertIsNone(o.value)
+
+    def test_something_optional(self) -> None:
+        o = bom_ref_from_str('foobar', optional=True)
+        self.assertIsInstance(o, BomRef)
+        self.assertEqual('foobar', o.value)
+
+    def test_something_mandatory(self) -> None:
+        o = bom_ref_from_str('foobar', optional=False)
+        self.assertIsInstance(o, BomRef)
+        self.assertEqual('foobar', o.value)