fix(catalogs): reject host-less catalog URLs in base and preset validators

the shared CatalogStackBase validator and PresetCatalog validator
checked parsed.netloc to enforce 'a valid URL with a host'. but netloc
is truthy for host-less URLs like https://:8080 or https://user@, so
those slipped through even though they have no host - contradicting the
error message. the workflow, step, and bundler validators already check
parsed.hostname (which is None in those cases); this aligns the two
stragglers with that. add regression tests covering port-only and
userinfo-only URLs.

Author: Quratulain-bilal

src/specify_cli/catalogs.py

@@ -78,7 +78,10 @@ def _validate_catalog_url(cls, url: str) -> None:
                 f"Catalog URL must use HTTPS (got {parsed.scheme}://). "
                 "HTTP is only allowed for localhost."
             )
-        if not parsed.netloc:
+        # Check hostname, not netloc: netloc is truthy for host-less URLs like
+        # "https://:8080" or "https://user@", so the host guarantee this error
+        # promises would not actually hold. hostname is None in those cases.
+        if not parsed.hostname:
             raise cls._error("Catalog URL must be a valid URL with a host.")
 
     def _load_catalog_config(self, config_path: Path) -> list[CatalogEntry] | None:

src/specify_cli/presets/__init__.py

@@ -1861,7 +1861,10 @@ def _validate_catalog_url(self, url: str) -> None:
                 f"Catalog URL must use HTTPS (got {parsed.scheme}://). "
                 "HTTP is only allowed for localhost."
             )
-        if not parsed.netloc:
+        # Check hostname, not netloc: netloc is truthy for host-less URLs like
+        # "https://:8080" or "https://user@", so the host guarantee this error
+        # promises would not actually hold. hostname is None in those cases.
+        if not parsed.hostname:
             raise PresetValidationError(
                 "Catalog URL must be a valid URL with a host."
             )

tests/integrations/test_integration_catalog.py

@@ -67,6 +67,22 @@ def test_missing_host_rejected(self):
         with pytest.raises(IntegrationCatalogError, match="valid URL"):
             IntegrationCatalog._validate_catalog_url("https:///no-host")
 
+    @pytest.mark.parametrize(
+        "url",
+        [
+            "https://:8080",       # port only, no host
+            "https://:0",          # port only, no host
+            "https://user@",       # userinfo only, no host
+            "https://user:pw@",    # userinfo only, no host
+        ],
+    )
+    def test_hostless_url_with_truthy_netloc_rejected(self, url):
+        # These have a truthy netloc (":8080", "user@") but no actual host,
+        # so a netloc-based check would wrongly accept them despite the
+        # "valid URL with a host" promise. hostname is None for all of them.
+        with pytest.raises(IntegrationCatalogError, match="valid URL"):
+            IntegrationCatalog._validate_catalog_url(url)
+
 
 # ---------------------------------------------------------------------------
 # IntegrationCatalog — active catalogs

tests/test_presets.py

@@ -1424,6 +1424,26 @@ def test_validate_catalog_url_localhost_http_allowed(self, project_dir):
         catalog._validate_catalog_url("http://localhost:8080/catalog.json")
         catalog._validate_catalog_url("http://127.0.0.1:8080/catalog.json")
 
+    @pytest.mark.parametrize(
+        "url",
+        [
+            "https://:8080",       # port only, no host
+            "https://:0",          # port only, no host
+            "https://user@",       # userinfo only, no host
+            "https://user:pw@",    # userinfo only, no host
+        ],
+    )
+    def test_validate_catalog_url_hostless_rejected(self, project_dir, url):
+        """Reject host-less URLs whose netloc is truthy but hostname is None.
+
+        ``urlparse('https://:8080').netloc`` is ``':8080'`` (truthy) but its
+        ``hostname`` is ``None``, so a netloc-based check would accept a URL
+        with no actual host, contradicting the "valid URL with a host" error.
+        """
+        catalog = PresetCatalog(project_dir)
+        with pytest.raises(PresetValidationError, match="valid URL with a host"):
+            catalog._validate_catalog_url(url)
+
     def test_env_var_catalog_url(self, project_dir, monkeypatch):
         """Test catalog URL from environment variable."""
         monkeypatch.setenv("SPECKIT_PRESET_CATALOG_URL", "https://custom.example.com/catalog.json")