fix(schemas): wrap LocalSchemaProvider JSON read in SchemaError

src/onedep_lib/schemas/local.py

@@ -13,6 +13,11 @@ def __init__(self, cache_dir: Path) -> None:
     def get_schema(self, schema_name: str) -> dict:
         cache_path = self._cache_dir / f"{schema_name}.json"
         if cache_path.exists():
-            with cache_path.open() as f:
-                return json.load(f)
+            try:
+                with cache_path.open() as f:
+                    return json.load(f)
+            except (ValueError, OSError) as exc:
+                raise SchemaError(
+                    f"Schema '{schema_name}' is corrupted or unreadable: {exc}"
+                ) from exc
         raise SchemaError(f"Schema '{schema_name}' not available")

tests/schemas/test_local.py

@@ -0,0 +1,27 @@
+import json
+from pathlib import Path
+
+import pytest
+
+from onedep_lib.exceptions import SchemaError
+from onedep_lib.schemas.local import LocalSchemaProvider
+
+SAMPLE_SCHEMA = {"$schema": "https://json-schema.org/draft/2020-12/schema", "type": "object"}
+
+
+def test_reads_schema_from_cache(tmp_path: Path):
+    (tmp_path / "required_files.json").write_text(json.dumps(SAMPLE_SCHEMA))
+    assert LocalSchemaProvider(tmp_path).get_schema("required_files") == SAMPLE_SCHEMA
+
+
+def test_missing_schema_raises_schema_error(tmp_path: Path):
+    with pytest.raises(SchemaError):
+        LocalSchemaProvider(tmp_path).get_schema("absent")
+
+
+def test_corrupted_schema_raises_schema_error(tmp_path: Path):
+    # A corrupted cache file must surface as SchemaError (the provider contract),
+    # not a raw json.JSONDecodeError - matching RemoteSchemaProvider.
+    (tmp_path / "required_files.json").write_text("{ not valid json")
+    with pytest.raises(SchemaError):
+        LocalSchemaProvider(tmp_path).get_schema("required_files")