Restore backwards compatibility on the legacy serializer

VERSION.txt

@@ -1 +1 @@
-0.13.2
+0.13.3

pulser-core/pulser/json/coders.py

@@ -101,6 +101,18 @@ def object_hook(self, obj: dict[str, Any]) -> Any:
         if not build:
             return cls
 
+        if "Device" in obj_name:
+            # Handle the removal of _channels for backwards compatibility
+            _channels = obj["__kwargs__"].pop("_channels", None)
+            channel_objs = obj["__kwargs__"].get("channel_objects", None)
+            channel_ids = obj["__kwargs__"].get("channel_ids", None)
+            if _channels and not (channel_ids or channel_objs):
+                _channels_dict = dict(_channels)
+                obj["__kwargs__"]["channel_ids"] = tuple(_channels_dict.keys())
+                obj["__kwargs__"]["channel_objects"] = tuple(
+                    _channels_dict.values()
+                )
+
         if "Sequence" in obj_name:
             seq = cls(*obj["__args__"], **obj["__kwargs__"])
             for name, args, kwargs in obj["calls"]:

pulser-core/requirements.txt

@@ -1,4 +1,4 @@
-jsonschema
+jsonschema < 4.18
 matplotlib
 # Numpy 1.20 introduces type hints, 1.24.0 breaks matplotlib < 3.6.1
 numpy >= 1.20, != 1.24.0

pulser-pasqal/requirements.txt

@@ -1 +1,2 @@
 pasqal-cloud ~= 0.2.3
+pydantic < 2.0

tests/test_json.py

@@ -210,3 +210,26 @@ def test_sequence_module():
     # Check that it also works
     s = json.dumps(obj_dict)
     Sequence.deserialize(s)
+
+
+def test_deprecation():
+    seq = Sequence(Register.square(1), MockDevice)
+
+    seq_dict = json.loads(seq.serialize())
+    dev_dict = seq_dict["__kwargs__"]["device"]
+
+    assert "_channels" not in dev_dict["__kwargs__"]
+    dev_dict["__kwargs__"]["_channels"] = []
+
+    s = json.dumps(seq_dict)
+    new_seq = Sequence.deserialize(s)
+    assert new_seq.device == MockDevice
+
+    ids = dev_dict["__kwargs__"].pop("channel_ids")
+    ch_objs = dev_dict["__kwargs__"].pop("channel_objects")
+    dev_dict["__kwargs__"]["_channels"] = tuple(zip(ids, ch_objs))
+
+    assert seq_dict["__kwargs__"]["device"] == dev_dict
+    s = json.dumps(seq_dict)
+    new_seq = Sequence.deserialize(s)
+    assert new_seq.device == MockDevice