Return an error message when attempting to copy a judgment to an exis…

…ting URI

If a newutral citation generates a URI which already exists in Marklogic, return
an error message and do not let the judgment be copied to that URI.

judgments/tests.py

@@ -170,6 +170,7 @@ def test_get_judgment_root_malformed_xml(self):
     def test_update_judgment_uri_success(self, fake_client):
         ds_caselaw_utils.neutral_url = MagicMock(return_value="new/uri")
         attrs = {
+            "get_judgment_xml.return_value": "",
             "copy_judgment.return_value": True,
             "delete_judgment.return_value": True,
         }
@@ -210,3 +211,14 @@ def test_update_judgment_uri_unparseable_citation(self):
 
         with self.assertRaises(judgments.utils.NeutralCitationToUriError):
             update_judgment_uri("old/uri", "Wrong neutral citation")
+
+    @patch("judgments.utils.api_client")
+    def test_update_judgment_uri_duplicate_uri(self, fake_client):
+        ds_caselaw_utils.neutral_url = MagicMock(return_value="new/uri")
+        attrs = {
+            "get_judgment_xml.return_value": "<akomaNtoso><judgment></judgment></akomaNtoso>",
+        }
+        fake_client.configure_mock(**attrs)
+
+        with self.assertRaises(judgments.utils.MoveJudgmentError):
+            update_judgment_uri("old/uri", "[2002] EAT 1")

judgments/utils.py

@@ -36,6 +36,13 @@ def update_judgment_uri(old_uri, new_citation):
             f"Unable to form new URI for {old_uri} from neutral citation: {new_citation}"
         )
 
+    existing_judgment = api_client.get_judgment_xml(new_uri, show_unpublished=True)
+    if existing_judgment != "":
+        raise MoveJudgmentError(
+            f"The URI {new_uri} generated from {new_citation} already exists, you cannot move this judgment to a"
+            f" pre-existing Neutral Citation Number."
+        )
+
     try:
         api_client.copy_judgment(old_uri, new_uri)
         set_metadata(old_uri, new_uri)