Validate that package name contains a namespace (#36)

* Validate that package name contains a namespace

* fix tests

* changelog

cookieplone/utils/validators.py

@@ -51,13 +51,15 @@ def validate_language_code(value: str) -> str:
 
 def validate_python_package_name(value: str) -> str:
     """Validate python_package_name is an identifier."""
-    status = False
-    if "." in value:
-        namespace, package = value.split(".")
-        status = namespace.isidentifier() and package.isidentifier()
-    else:
-        status = value.isidentifier()
-    return "" if status else f"'{value}' is not a valid Python identifier."
+    parts = value.split(".")
+    if any(not part.isidentifier() for part in parts):
+        return f"'{value}' is not a valid Python identifier."
+    if len(parts) != 2:
+        return (
+            "The Python package name must contain a single namespace "
+            "(e.g. collective.something)"
+        )
+    return ""
 
 
 def validate_hostname(value: str) -> str:

news/36.bugfix

@@ -0,0 +1 @@
+Show a more helpful error message if user enters a Python package name without a namespace. @davisagli

tests/utils/test_validators.py

@@ -73,10 +73,22 @@ def test_validate_language_code(value: str, expected: str):
         (" ", "' ' is not a valid Python identifier."),
         ("", "'' is not a valid Python identifier."),
         ("project title", "'project title' is not a valid Python identifier."),
-        ("project_title", ""),
+        (
+            "project_title",
+            "The Python package name must contain a single namespace "
+            "(e.g. collective.something)",
+        ),
         ("project-title", "'project-title' is not a valid Python identifier."),
-        ("projecttitle", ""),
-        ("projectTitle", ""),
+        (
+            "projecttitle",
+            "The Python package name must contain a single namespace "
+            "(e.g. collective.something)",
+        ),
+        (
+            "projectTitle",
+            "The Python package name must contain a single namespace "
+            "(e.g. collective.something)",
+        ),
         ("project.title", ""),
     ),
 )