From 51a6cdf0793ae5cea70ef5b812af332349a0fa58 Mon Sep 17 00:00:00 2001
From: marcelsafin <179933638+marcelsafin@users.noreply.github.com>
Date: Wed, 12 Aug 2026 23:53:45 +0200
Subject: [PATCH] fix(presets): reject falsy non-mapping catalog roots

Assisted-by: GitHub Copilot (model: gpt-5.6-sol, autonomous)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
---
 src/specify_cli/presets/__init__.py |  4 +++-
 tests/test_presets.py               | 11 +++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/specify_cli/presets/__init__.py b/src/specify_cli/presets/__init__.py
index 6a359f5b29..a7405578da 100644
--- a/src/specify_cli/presets/__init__.py
+++ b/src/specify_cli/presets/__init__.py
@@ -4276,11 +4276,13 @@ def _load_catalog_config(self, config_path: Path) -> Optional[List[PresetCatalog
         if not config_path.exists():
             return None
         try:
-            data = yaml.safe_load(config_path.read_text(encoding="utf-8")) or {}
+            data = yaml.safe_load(config_path.read_text(encoding="utf-8"))
         except (yaml.YAMLError, OSError, UnicodeError) as e:
             raise PresetValidationError(
                 f"Failed to read catalog config {config_path}: {e}"
             )
+        if data is None:
+            return None
         if not isinstance(data, dict):
             raise PresetValidationError(
                 f"Invalid catalog config {config_path}: expected a mapping at root, got {type(data).__name__}"
diff --git a/tests/test_presets.py b/tests/test_presets.py
index 317a1b437c..7d634a67cf 100644
--- a/tests/test_presets.py
+++ b/tests/test_presets.py
@@ -3324,6 +3324,17 @@ def test_load_catalog_config_empty(self, project_dir):
         result = catalog._load_catalog_config(config_path)
         assert result is None
 
+    @pytest.mark.parametrize("bad", [[], False, 0, ""])
+    def test_load_catalog_config_rejects_falsy_non_mapping_root(
+        self, project_dir, bad
+    ):
+        config_path = project_dir / ".specify" / "preset-catalogs.yml"
+        config_path.write_text(yaml.safe_dump(bad), encoding="utf-8")
+
+        catalog = PresetCatalog(project_dir)
+        with pytest.raises(PresetValidationError, match="expected a mapping"):
+            catalog._load_catalog_config(config_path)
+
     def test_load_catalog_config_invalid_yaml(self, project_dir):
         """Test loading invalid YAML raises error."""
         config_path = project_dir / ".specify" / "preset-catalogs.yml"