Merge pull request #47 from qua-platform/fix/instantiate-union-pipe

feat: Add support for instantiating union types

CHANGELOG.md

@@ -7,8 +7,10 @@
 - Allow `QuamBase.get_reference(attr)` to return a reference of one of its attributes
 
 ### Fixed
+- Fix quam object instantiation error when a parameter type uses pipe operator
 - Allow int keys to be serialised / loaded in QuAM using JSONSerialiser
 
+
 ## [0.3.3]
 ### Added
 - Added the following parameters to `IQChannel`: `RF_frequency`, `LO_frequency`, `intermediate_frequency`

quam/core/quam_instantiation.py

@@ -1,4 +1,6 @@
 from __future__ import annotations
+import sys
+import types
 import typing
 from typing import TYPE_CHECKING, Dict, Any
 from inspect import isclass
@@ -16,6 +18,12 @@
     from quam.core import QuamBase
 
 
+if sys.version_info < (3, 10):
+    union_types = (typing.Union,)
+else:
+    union_types = [typing.Union, types.UnionType]
+
+
 def instantiate_attrs_from_dict(
     attr_dict: dict,
     required_type: type,
@@ -224,7 +232,7 @@ def instantiate_attr(
         )
         if typing.get_origin(expected_type) == dict:
             expected_type = dict
-    elif typing.get_origin(expected_type) == typing.Union:
+    elif typing.get_origin(expected_type) in union_types:
         for union_type in typing.get_args(expected_type):
             try:
                 instantiated_attr = instantiate_attr(

tests/instantiation/test_instantiation.py

@@ -1,6 +1,8 @@
 import pytest
 from typing import List, Literal, Optional, Tuple, Union
 
+from pytest_cov.engine import sys
+
 from quam.core import QuamRoot, QuamComponent, quam_dataclass
 from quam.core.quam_classes import QuamDict
 from quam.examples.superconducting_qubits.components import Transmon
@@ -339,6 +341,7 @@ def test_instantiate_dict_referenced():
 
     assert attrs == {"test_attr": "#./reference"}
 
+
 @quam_dataclass
 class TestQuamComponent(QuamComponent):
     a: int
@@ -357,3 +360,19 @@ class TestQuamUnion(QuamComponent):
 
     with pytest.raises(TypeError):
         instantiate_quam_class(TestQuamUnion, {"union_val": {"a": "42"}})
+
+
+@pytest.mark.skipif(sys.version_info < (3, 10), reason="requires python3.10 or higher")
+def test_instantiation_pipe_union_type():
+    @quam_dataclass
+    class TestQuamUnion(QuamComponent):
+        union_val: int | TestQuamComponent
+
+    obj = instantiate_quam_class(TestQuamUnion, {"union_val": 42})
+    assert obj.union_val == 42
+
+    obj = instantiate_quam_class(TestQuamUnion, {"union_val": {"a": 42}})
+    assert obj.union_val.a == 42
+
+    with pytest.raises(TypeError):
+        instantiate_quam_class(TestQuamUnion, {"union_val": {"a": "42"}})