🐛 Use nbformat for write_notebook

nbproject/dev/_notebook.py

@@ -1,6 +1,7 @@
 from pathlib import Path
 from typing import Union
 
+import nbformat
 import orjson
 from pydantic import BaseModel
 
@@ -25,10 +26,11 @@
             nb = orjson.loads(f.read())
         except orjson.JSONDecodeError as e:
             if "Input is a zero-length, empty document" in str(e):
-                raise ValueError("Notebook cannot be empty. It must have at least a title cell.")
+                raise ValueError(
+                    "Notebook cannot be empty. It must have at least a title cell."
+                ) from e
             else:
-                raise
-
+                raise e
 
     return Notebook(**nb)
 
@@ -40,7 +42,5 @@
         nb: Notebook to write.
         filepath: Path where to write the notebook.
     """
-    with open(filepath, "wb") as f:
-        # the formatting orjson dumps doesn't match jupyter lab
-        # maybe one can homogenize it at some point
-        f.write(orjson.dumps(nb.dict(), option=orjson.OPT_INDENT_2))
+    nb_node = nbformat.from_dict(nb.dict())
+    nbformat.write(nb_node, filepath, version=nbformat.NO_CONVERT)

pyproject.toml

@@ -19,6 +19,7 @@ dependencies = [
     "pyyaml",
     "packaging",
     "orjson",
+    "nbformat",
     "ipylab",
     "importlib-metadata",
     "stdlib_list; python_version < '3.10'",