update contributing guide and handle json decoder error (#36)

Co-authored-by: Jay Hack <jayhack@users.noreply.github.com>

Author: tomcodgen

CONTRIBUTING.md

@@ -34,13 +34,17 @@ source .venv/bin/activate
 uv sync --dev
 ```
 
+> [!TIP]
+> - If sync fails with `missing field 'version'`, you may need to delete lockfile and rerun `rm uv.lock && uv sync --dev`.
+> - If sync fails with failed compilation, you may need to install clang and rerun `uv sync --dev`.
+
 ### Running Tests
 
 ```bash
-# Unit tests
+# Unit tests (tests atomic functionality)
 uv run pytest tests/unit -n auto
 
-# Codemod tests
+# Codemod tests (tests larger programs)
 uv run pytest tests/codemod/test_codemods.py -n auto
 ```
 

src/graph_sitter/testing/models.py

@@ -26,7 +26,7 @@
 
 try:
     REPO_ID_TO_URL = json.loads((TEST_DIR / "repos" / "repos.json").read_text())
-except FileNotFoundError:
+except (FileNotFoundError, json.decoder.JSONDecodeError):
     REPO_ID_TO_URL = {}
 if TYPE_CHECKING:
     from graph_sitter.codemod import Codemod3