fix(bundler): reject falsy non-list bundles/contributed_components in records (#3666)

load_records and InstalledBundleRecord.from_dict defaulted their list fields
with `data.get(...) or []` BEFORE the isinstance(list) guard, so a FALSY
non-list value (0, '', False, {}) was coerced to [] and the guard became dead
code — a corrupt .specify/bundle-records.json was silently read as "no
bundles"/"no components" instead of raising. Only an absent/None value should
mean empty.

Handle None explicitly and reject every other non-list, mirroring the merged
requires/provides/integration guards (#3629, #3661) and the catalog_config
sibling reader.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/specify_cli/bundler/models/records.py

@@ -55,8 +55,13 @@ class InstalledBundleRecord:
     def from_dict(cls, data: Any) -> "InstalledBundleRecord":
         if not isinstance(data, dict):
             raise BundlerError("Each installed-bundle record must be a mapping.")
-        components_raw = data.get("contributed_components") or []
-        if not isinstance(components_raw, list):
+        components_raw = data.get("contributed_components")
+        if components_raw is None:
+            components_raw = []
+        elif not isinstance(components_raw, list):
+            # `or []` would coerce a FALSY non-list (0, '', False, {}) to []
+            # before this guard, silently accepting a corrupt record; only an
+            # absent/None value means "no components".
             raise BundlerError(
                 "Corrupt record: 'contributed_components' must be a list."
             )
@@ -121,8 +126,13 @@ def load_records(project_root: Path) -> list[InstalledBundleRecord]:
     if not isinstance(data, dict):
         raise BundlerError(f"Corrupt records file: {path}")
     _check_schema_version(data.get("schema_version"), path=path, required=True)
-    bundles = data.get("bundles") or []
-    if not isinstance(bundles, list):
+    bundles = data.get("bundles")
+    if bundles is None:
+        bundles = []
+    elif not isinstance(bundles, list):
+        # `or []` would coerce a FALSY non-list (0, '', False, {}) to [] before
+        # this guard, silently treating a corrupt file as "no bundles"; only an
+        # absent/None value means empty.
         raise BundlerError(
             f"Corrupt records file: {path} — 'bundles' must be a list."
         )

tests/unit/test_bundler_records.py

@@ -45,6 +45,27 @@ def test_load_missing_file_returns_empty(tmp_path: Path):
     assert load_records(tmp_path) == []
 
 
+@pytest.mark.parametrize("bad", [0, False, "", {}])
+def test_load_records_rejects_falsy_non_list_bundles(tmp_path: Path, bad):
+    # `data.get("bundles") or []` coerced a FALSY non-list (0, '', False, {})
+    # to [] before the isinstance guard, silently treating a corrupt records
+    # file as "no bundles". Only an absent/None value means empty.
+    (tmp_path / ".specify").mkdir()
+    records_path(tmp_path).write_text(
+        json.dumps({"schema_version": "1.0", "bundles": bad}), encoding="utf-8"
+    )
+    with pytest.raises(BundlerError, match="'bundles' must be a list"):
+        load_records(tmp_path)
+
+
+@pytest.mark.parametrize("bad", [0, False, "", {}])
+def test_from_dict_rejects_falsy_non_list_contributed_components(bad):
+    # Same falsy-coercion hole for a record's 'contributed_components'.
+    data = {"bundle_id": "a", "version": "1.0.0", "contributed_components": bad}
+    with pytest.raises(BundlerError, match="'contributed_components' must be a list"):
+        InstalledBundleRecord.from_dict(data)
+
+
 def test_corrupt_priority_raises_actionable_error(tmp_path: Path):
     (tmp_path / ".specify").mkdir()
     rec = _record("a", [("presets", "p1")])