Refactor package case check

Refactor package case check so that logic is directly in package_manifest.py,
rather than hidden in a poorly named util function
Update test to reflect that updating packages that already exist with different
case should still be valid

django/thunderstore/repository/package_manifest.py

@@ -13,11 +13,7 @@
     PackageVersionField,
     StrictCharField,
 )
-from thunderstore.repository.utils import (
-    does_contain_package,
-    has_different_case,
-    has_duplicate_packages,
-)
+from thunderstore.repository.utils import does_contain_package, has_duplicate_packages
 
 
 class PackageInstallerSerializer(serializers.Serializer):
@@ -100,10 +96,13 @@ def validate(self, data):
             )
         if does_contain_package(result["dependencies"], reference):
             raise ValidationError("Package depending on itself is not allowed")
-        if has_different_case(reference.without_version):
-            raise ValidationError(
-                "Package name already exists with different capitalization"
-            )
+        if not reference.without_version.exists:  # if we're making a new package
+            if (
+                reference.without_version.exists_in_any_case
+            ):  # if it exists in a different case
+                raise ValidationError(
+                    "Package name already exists with different capitalization"
+                )
         return result
 
     def update(self, instance, validated_data):

django/thunderstore/repository/tests/test_package_manifest.py

@@ -75,6 +75,16 @@ def test_manifest_v1_serializer_package_already_exists_with_different_case(
     assert "Package name already exists with different capitalization" in str(
         serializer.errors["non_field_errors"][0]
     )
+    # Updating packages that already exist with different case should still be valid
+    PackageFactory(
+        owner=package.owner, name=package.name.swapcase(), namespace=package.namespace
+    )
+    serializer = ManifestV1Serializer(
+        user=user,
+        team=package.owner,
+        data=manifest_v1_data,
+    )
+    assert serializer.is_valid() is True
 
 
 @pytest.mark.django_db

django/thunderstore/repository/utils.py

@@ -42,14 +42,6 @@ def has_duplicate_packages(packages: List["PackageReference"]) -> bool:
     return False
 
 
-def has_different_case(reference: "PackageReference") -> bool:
-    if reference.exists:
-        return False
-    elif reference.exists_in_any_case:
-        return True
-    return False
-
-
 def unpack_serializer_errors(field, errors, error_dict=None):
     if error_dict is None:
         error_dict = {}