.beb and .json serialization of the document

tests/unit/test_models.py

@@ -0,0 +1,14 @@
+"""Basic smoke tests for the core model."""
+
+from __future__ import annotations
+
+import pytest
+
+from bedit_core.models import Document, GraphImplementation
+
+
+@pytest.mark.unit
+def test_minimal_document_has_graph_root(minimal_document: Document) -> None:
+    root = next(iter(minimal_document.root.values()))
+
+    assert isinstance(root.implementation, GraphImplementation)

tests/unit/test_serialization.py

@@ -0,0 +1,17 @@
+"""Basic smoke tests for document serialization."""
+
+from __future__ import annotations
+
+import pytest
+
+from bedit_core.models import Document
+from bedit_core.serialization import load, save
+
+
+@pytest.mark.unit
+def test_json_round_trip(tmp_path, minimal_document: Document) -> None:
+    path = tmp_path / "document.json"
+
+    save(minimal_document, path)
+
+    assert load(path) == minimal_document