Use the orjson equivalent default encoder when save_json is passed the default encoder (#74377)

tests/util/test_json.py

@@ -5,12 +5,13 @@ from json import JSONEncoder, dumps
 import math
 import os
 from tempfile import mkdtemp
-from unittest.mock import Mock
+from unittest.mock import Mock, patch
 
 import pytest
 
 from homeassistant.core import Event, State
 from homeassistant.exceptions import HomeAssistantError
+from homeassistant.helpers.json import JSONEncoder as DefaultHASSJSONEncoder
 from homeassistant.helpers.template import TupleWrapper
 from homeassistant.util.json import (
     SerializationError,
@@ -127,6 +128,21 @@ def test_custom_encoder():
     assert data == "9"
 
 
+def test_default_encoder_is_passed():
+    """Test we use orjson if they pass in the default encoder."""
+    fname = _path_for("test6")
+    with patch(
+        "homeassistant.util.json.orjson.dumps", return_value=b"{}"
+    ) as mock_orjson_dumps:
+        save_json(fname, {"any": 1}, encoder=DefaultHASSJSONEncoder)
+    assert len(mock_orjson_dumps.mock_calls) == 1
+    # Patch json.dumps to make sure we are using the orjson path
+    with patch("homeassistant.util.json.json.dumps", side_effect=Exception):
+        save_json(fname, {"any": {1}}, encoder=DefaultHASSJSONEncoder)
+    data = load_json(fname)
+    assert data == {"any": [1]}
+
+
 def test_find_unserializable_data():
     """Find unserializeable data."""
     assert find_paths_unserializable_data(1) == {}