fix(bob): fail closed on malformed preset entries too (review #3415)

Address review 4745191015: the preset guard read a parseable registry but
silently skipped malformed per-preset metadata and treated a malformed
registered_commands value as "no matching artifacts". A registry such as
{"presets":{"p1":[]}} therefore allowed a layout migration even though p1's
ownership is unknown, risking deletion of preset-managed files. Now raise
_PresetRegistryUnreadableError for a non-dict preset entry, a non-dict
registered_commands, or a non-list registered_skills. Extend the unit test
to cover these malformed shapes.

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Author: mnriem

src/specify_cli/integrations/_migrate_commands.py

@@ -105,14 +105,24 @@ def _installed_presets_affecting_agent(project_root, agent_key: str) -> list[str
 
     affected: list[str] = []
     for preset_id, meta in data.get("presets", {}).items():
+        # A malformed entry means we cannot verify whether this preset owns
+        # artifacts for the agent, so fail closed rather than skip it.
         if not isinstance(meta, dict):
-            continue
+            raise _PresetRegistryUnreadableError(
+                f"preset '{preset_id}' entry is malformed"
+            )
         registered_commands = meta.get("registered_commands", {})
-        has_commands = (
-            isinstance(registered_commands, dict)
-            and bool(registered_commands.get(agent_key))
-        )
-        has_skills = bool(meta.get("registered_skills"))
+        if not isinstance(registered_commands, dict):
+            raise _PresetRegistryUnreadableError(
+                f"preset '{preset_id}' registered_commands is malformed"
+            )
+        registered_skills = meta.get("registered_skills", [])
+        if not isinstance(registered_skills, (list, tuple)):
+            raise _PresetRegistryUnreadableError(
+                f"preset '{preset_id}' registered_skills is malformed"
+            )
+        has_commands = bool(registered_commands.get(agent_key))
+        has_skills = bool(registered_skills)
         if has_commands or has_skills:
             affected.append(preset_id)
     return affected

tests/integrations/test_integration_subcommand.py

@@ -2943,6 +2943,29 @@ def test_installed_presets_affecting_agent_absent_vs_unreadable(self, tmp_path):
         with pytest.raises(_PresetRegistryUnreadableError):
             _installed_presets_affecting_agent(project, "bob")
 
+        # Malformed per-preset entry (not a dict) → ownership unknown → raise.
+        registry.write_text(
+            json.dumps({"presets": {"p1": []}}), encoding="utf-8"
+        )
+        with pytest.raises(_PresetRegistryUnreadableError):
+            _installed_presets_affecting_agent(project, "bob")
+
+        # Malformed registered_commands (not a dict) → raise.
+        registry.write_text(
+            json.dumps({"presets": {"p1": {"registered_commands": []}}}),
+            encoding="utf-8",
+        )
+        with pytest.raises(_PresetRegistryUnreadableError):
+            _installed_presets_affecting_agent(project, "bob")
+
+        # Malformed registered_skills (not a list) → raise.
+        registry.write_text(
+            json.dumps({"presets": {"p1": {"registered_skills": {}}}}),
+            encoding="utf-8",
+        )
+        with pytest.raises(_PresetRegistryUnreadableError):
+            _installed_presets_affecting_agent(project, "bob")
+
         # Valid, empty registry → empty list.
         registry.write_text(json.dumps({"presets": {}}), encoding="utf-8")
         assert _installed_presets_affecting_agent(project, "bob") == []