Python 3.8 and fixes

codecov.yml

@@ -0,0 +1,16 @@
+comment: false
+
+coverage:
+  status:
+    project:
+      default:
+        target: "97"
+    patch:
+      default:
+        target: "100"
+
+ignore:
+  - "setup.py"
+  - "*/tests/.*"
+  - "__init__.py"
+  - "tests/*.py"

mytree/mytree.py

@@ -31,9 +31,13 @@ def __init_subclass__(cls, mutable: bool = False):
 
     def replace(self, **kwargs: Any) -> Mytree:
         """
-        Replace the values of the fields of the object with the values of the
-        keyword arguments. A new object will be created with the same
-        type as the original object.
+        Replace the values of the fields of the object.
+
+        Args:
+            **kwargs: keyword arguments to replace the fields of the object.
+
+        Returns:
+            Mytree: with the fields replaced.
         """
         fields = vars(self)
         for key in kwargs:
@@ -46,31 +50,37 @@ def replace(self, **kwargs: Any) -> Mytree:
 
     def replace_meta(self, **kwargs: Any) -> Mytree:
         """
-        Replace the values of the fields of the object with the values of the
-        keyword arguments. If the object is a dataclass, `dataclasses.replace`
-        will be used. Otherwise, a new object will be created with the same
-        type as the original object.
+        Replace the metadata of the fields.
+
+        Args:
+            **kwargs: keyword arguments to replace the metadata of the fields of the object.
+
+        Returns:
+            Mytree: with the metadata of the fields replaced.
         """
+        fields = vars(self)
         for key in kwargs:
-            if key not in self._pytree__meta.keys():
-                raise ValueError(f"'{key}' is not a leaf of {type(self).__name__}")
+            if key not in fields:
+                raise ValueError(f"'{key}' is not a field of {type(self).__name__}")
 
         pytree = copy(self)
         pytree.__dict__.update(_pytree__meta={**pytree._pytree__meta, **kwargs})
         return pytree
 
     def update_meta(self, **kwargs: Any) -> Mytree:
         """
-        Replace the values of the fields of the object with the values of the
-        keyword arguments. If the object is a dataclass, `dataclasses.replace`
-        will be used. Otherwise, a new object will be created with the same
-        type as the original object.
+        Update the metadata of the fields. The metadata must already exist.
+
+        Args:
+            **kwargs: keyword arguments to replace the fields of the object.
+
+        Returns:
+            Mytree: with the fields replaced.
         """
+        fields = vars(self)
         for key in kwargs:
-            if key not in self._pytree__meta.keys():
-                raise ValueError(
-                    f"'{key}' is not an attribute of {type(self).__name__}"
-                )
+            if key not in fields:
+                raise ValueError(f"'{key}' is not a field of {type(self).__name__}")
 
         pytree = copy(self)
         new = deepcopy(pytree._pytree__meta)
@@ -82,13 +92,13 @@ def update_meta(self, **kwargs: Any) -> Mytree:
         pytree.__dict__.update(_pytree__meta=new)
         return pytree
 
-    def replace_trainable(Mytree: Mytree, **kwargs: Dict[str, bool]) -> Mytree:
+    def replace_trainable(self: Mytree, **kwargs: Dict[str, bool]) -> Mytree:
         """Replace the trainability status of local nodes of the Mytree."""
-        return Mytree.update_meta(**{k: {"trainable": v} for k, v in kwargs.items()})
+        return self.update_meta(**{k: {"trainable": v} for k, v in kwargs.items()})
 
-    def replace_bijector(Mytree: Mytree, **kwargs: Dict[str, Bijector]) -> Mytree:
+    def replace_bijector(self: Mytree, **kwargs: Dict[str, Bijector]) -> Mytree:
         """Replace the bijectors of local nodes of the Mytree."""
-        return Mytree.update_meta(**{k: {"bijector": v} for k, v in kwargs.items()})
+        return self.update_meta(**{k: {"bijector": v} for k, v in kwargs.items()})
 
     def constrain(self) -> Mytree:
         """Transform model parameters to the constrained space according to their defined bijectors.

setup.py

@@ -47,7 +47,7 @@ def read(*local_path: str) -> str:
         long_description=read("README.md"),
         long_description_content_type="text/markdown",
         packages=find_packages(".", exclude=["tests"]),
-        python_requires=">=3.9",
+        python_requires=">=3.8",
         install_requires=INSTALL_REQUIRES,
         extras_require=EXTRA_REQUIRE,
         zip_safe=True,

tests/test_mytree.py

@@ -172,6 +172,28 @@ def loss_fn(model):
     assert grad.weight == 0.0
     assert grad.bias == 2.0
 
+    new = model.replace_meta(bias={"amazing": True})
+    assert new.weight == 1.0
+    assert new.bias == 2.0
+    assert model.weight == 1.0
+    assert model.bias == 2.0
+    assert meta(new).bias == {"amazing": True}
+    assert meta(model).bias == {}
+
+    with pytest.raises(ValueError, match=f"'cool' is not a field of SimpleModel"):
+        model.replace_meta(cool={"don't": "think so"})
+
+    with pytest.raises(ValueError, match=f"'cool' is not a field of SimpleModel"):
+        model.update_meta(cool={"don't": "think so"})
+
+    new = model.update_meta(bias={"amazing": True})
+    assert new.weight == 1.0
+    assert new.bias == 2.0
+    assert model.weight == 1.0
+    assert model.bias == 2.0
+    assert meta(new).bias == {"amazing": True}
+    assert meta(model).bias == {}
+
 
 @pytest.mark.parametrize("is_dataclass", [True, False])
 def test_nested_mytree_structure(is_dataclass):