Fix substring matching on cpan and mlflow type checks

CHANGELOG.rst

@@ -11,6 +11,9 @@ Changelog
 - Fix type hint for ``BasePurlType.allowed_qualifiers``
   https://github.com/package-url/packageurl-python/pull/213
 
+- Fix substring matching on the ``cpan`` and ``mlflow`` type checks
+  https://github.com/package-url/packageurl-python/pull/232
+
 0.17.6 (2025-11-24)
 -------------------
 

src/packageurl/__init__.py

@@ -149,7 +149,7 @@ def normalize_namespace(
         "hex",
     ):
         namespace_str = namespace_str.lower()
-    if ptype and ptype in ("cpan"):
+    if ptype == "cpan":
         namespace_str = namespace_str.upper()
     segments = [seg for seg in namespace_str.split("/") if seg.strip()]
     segments_quoted = map(get_quoter(encode), segments)
@@ -189,7 +189,7 @@ def normalize_name(
     quoter = get_quoter(encode)
     name_str = quoter(name_str)
     name_str = name_str.strip().strip("/")
-    if ptype and ptype in ("mlflow"):
+    if ptype == "mlflow":
         return normalize_mlflow_name(name_str, qualifiers)
     if ptype in (
         "bitbucket",

tests/test_packageurl.py

@@ -31,6 +31,8 @@
 
 from packageurl import PackageURL
 from packageurl import normalize
+from packageurl import normalize_name
+from packageurl import normalize_namespace
 from packageurl import normalize_qualifiers
 
 
@@ -388,3 +390,23 @@ def test_no_encoding_to_string():
         p.to_string(encode=False)
         == "pkg:nuget/an:odd:space/libiconv: character set conversion library@1.9?package-id=e11a609df352e292"
     )
+
+
+def test_cpan_namespace_uppercasing_is_not_applied_to_substring_types() -> None:
+    assert normalize_namespace("Some-Namespace", "cpan") == "SOME-NAMESPACE"
+
+    for ptype in ("pan", "cpa", "c", "a", "cp", "an"):
+        assert normalize_namespace("Some-Namespace", ptype) == "Some-Namespace"
+
+    assert PackageURL(type="pan", namespace="Some-Namespace", name="x").to_string() == (
+        "pkg:pan/Some-Namespace/x"
+    )
+
+
+def test_mlflow_name_handling_is_not_applied_to_substring_types() -> None:
+    databricks = {"repository_url": "https://community.cloud.databricks.com"}
+
+    assert normalize_name("MyModel", databricks, "mlflow") == "mymodel"
+
+    for ptype in ("ml", "flow", "low", "m", "w"):
+        assert normalize_name("MyModel", databricks, ptype) == "MyModel"