Add support for JSON fragments (#107213)

tests/helpers/test_json.py

@@ -19,12 +19,15 @@ from homeassistant.helpers.json import (
     json_bytes_strip_null,
     json_dumps,
     json_dumps_sorted,
+    json_fragment,
     save_json,
 )
 from homeassistant.util import dt as dt_util
 from homeassistant.util.color import RGBColor
 from homeassistant.util.json import SerializationError, load_json
 
+from tests.common import json_round_trip
+
 # Test data that can be saved as JSON
 TEST_JSON_A = {"a": 1, "B": "two"}
 TEST_JSON_B = {"a": "one", "B": 2}
@@ -45,7 +48,8 @@ def test_json_encoder(hass: HomeAssistant, encoder: type[json.JSONEncoder]) -> N
     assert sorted(ha_json_enc.default(data)) == sorted(data)
 
     # Test serializing an object which implements as_dict
-    assert ha_json_enc.default(state) == state.as_dict()
+    default = ha_json_enc.default(state)
+    assert json_round_trip(default) == json_round_trip(state.as_dict())
 
 
 def test_json_encoder_raises(hass: HomeAssistant) -> None:
@@ -133,6 +137,35 @@ def test_json_dumps_rgb_color_subclass() -> None:
     assert json_dumps(rgb) == "[4,2,1]"
 
 
+def test_json_fragments() -> None:
+    """Test the json dumps with a fragment."""
+
+    assert (
+        json_dumps(
+            [
+                json_fragment('{"inner":"fragment2"}'),
+                json_fragment('{"inner":"fragment2"}'),
+            ]
+        )
+        == '[{"inner":"fragment2"},{"inner":"fragment2"}]'
+    )
+
+    class Fragment1:
+        @property
+        def json_fragment(self):
+            return json_fragment('{"inner":"fragment1"}')
+
+    class Fragment2:
+        @property
+        def json_fragment(self):
+            return json_fragment('{"inner":"fragment2"}')
+
+    assert (
+        json_dumps([Fragment1(), Fragment2()])
+        == '[{"inner":"fragment1"},{"inner":"fragment2"}]'
+    )
+
+
 def test_json_bytes_strip_null() -> None:
     """Test stripping nul from strings."""