dataclass types now accept class_path and init_args as value

.pre-commit-config.yaml

@@ -56,6 +56,7 @@ repos:
       [
         types-PyYAML,
         types-requests,
+        types-setuptools,
       ]
     verbose: true
 

CHANGELOG.rst

@@ -21,6 +21,8 @@ Added
   <https://github.com/omni-us/jsonargparse/pull/554>`__).
 - Support for ``NotRequired`` and ``Required`` annotations for ``TypedDict``
   keys (`#571 <https://github.com/omni-us/jsonargparse/pull/571>`__).
+- ``dataclass`` types now accept ``class_path`` and ``init_args`` as value
+  (`#581 <https://github.com/omni-us/jsonargparse/pull/581>`__).
 
 Fixed
 ^^^^^
@@ -38,8 +40,7 @@ Changed
 - Removed shtab experimental warning (`#561
   <https://github.com/omni-us/jsonargparse/pull/561>`__).
 - For consistency ``add_subclass_arguments`` now sets default ``None`` instead
-  of ``SUPPRESS`` (`lightning#20103
-  <https://github.com/Lightning-AI/pytorch-lightning/issue/20103>`__).
+  of ``SUPPRESS`` (`#568 <https://github.com/omni-us/jsonargparse/pull/568>`__).
 
 
 v4.32.1 (2024-08-23)

jsonargparse/_core.py

@@ -321,7 +321,7 @@ def _parse_common(
             except Exception as ex:
                 self.error(str(ex), ex)
 
-            if not skip_check and not lenient_check.get():
+            if not skip_check:
                 self.check_config(cfg, skip_required=skip_required)
 
         if not (with_meta or (with_meta is None and self._default_meta)):
@@ -675,8 +675,10 @@ def add_subcommands(self, required: bool = True, dest: str = "subcommand", **kwa
         """
         if "description" not in kwargs:
             kwargs["description"] = "For more details of each subcommand, add it as an argument followed by --help."
-        with parser_context(parent_parser=self, lenient_check=True):
-            subcommands: _ActionSubCommands = super().add_subparsers(dest=dest, **kwargs)  # type: ignore[assignment]
+        default_config_files = self.default_config_files
+        self.default_config_files = []
+        subcommands: _ActionSubCommands = super().add_subparsers(dest=dest, **kwargs)  # type: ignore[assignment]
+        self.default_config_files = default_config_files
         if required:
             self.required_args.add(dest)
         subcommands._required = required  # type: ignore[attr-defined]
@@ -1069,7 +1071,7 @@ def check_values(cfg):
                             continue
                 val = cfg[key]
                 if action is not None:
-                    if val is None and skip_none:
+                    if (val is None and skip_none) or lenient_check.get():
                         continue
                     try:
                         self._check_value_key(action, val, key, ccfg)
@@ -1397,7 +1399,7 @@ def default_config_files(self) -> List[str]:
         return self._default_config_files
 
     @default_config_files.setter
-    def default_config_files(self, default_config_files: Optional[List[Union[str, os.PathLike]]]):
+    def default_config_files(self, default_config_files: Optional[Sequence[Union[str, os.PathLike]]]):
         if default_config_files is None:
             self._default_config_files = []
         elif isinstance(default_config_files, list) and all(

jsonargparse/_typehints.py

@@ -633,6 +633,8 @@ def get_class_parser(val_class, sub_add_kwargs=None, skip_args=0):
         kwargs = dict(sub_add_kwargs) if sub_add_kwargs else {}
         if skip_args:
             kwargs.setdefault("skip", set()).add(skip_args)
+        if is_subclass_spec(kwargs.get("default")):
+            kwargs["default"] = kwargs["default"].get("init_args")
         parser = parent_parser.get()
         parser = type(parser)(exit_on_error=False, logger=parser.logger, parser_mode=parser.parser_mode)
         remove_actions(parser, (ActionConfigFile, _ActionPrintConfig))
@@ -1010,6 +1012,8 @@ def adapt_typehints(
         if serialize:
             val = load_value(parser.dump(val, **dump_kwargs.get()))
         elif isinstance(val, (dict, Namespace)):
+            if is_subclass_spec(val) and get_import_path(typehint) == val.get("class_path"):
+                val = val.get("init_args")
             val = parser.parse_object(val, defaults=sub_defaults.get() or list_item)
         elif isinstance(val, NestedArg):
             prev_val = prev_val if isinstance(prev_val, Namespace) else None

jsonargparse_tests/test_dataclass_like.py

@@ -502,6 +502,46 @@ def test_nested_generic_dataclass(parser):
     assert "--x.y.g4 g4          (required, type: dict[str, union[float, bool]])" in help_str
 
 
+# union mixture tests
+
+
+@dataclasses.dataclass
+class UnionData:
+    data_a: int = 1
+    data_b: Optional[str] = None
+
+
+class UnionClass:
+    def __init__(self, prm_1: float, prm_2: bool):
+        self.prm_1 = prm_1
+        self.prm_2 = prm_2
+
+
+@pytest.mark.parametrize(
+    "union_type",
+    [
+        Union[UnionData, UnionClass],
+        Union[UnionClass, UnionData],
+    ],
+)
+def test_class_path_union_mixture_dataclass_and_class(parser, union_type):
+    parser.add_argument("--union", type=union_type, enable_path=True)
+
+    value = {"class_path": f"{__name__}.UnionData", "init_args": {"data_a": 2, "data_b": "x"}}
+    cfg = parser.parse_args([f"--union={json.dumps(value)}"])
+    init = parser.instantiate_classes(cfg)
+    assert isinstance(init.union, UnionData)
+    assert dataclasses.asdict(init.union) == {"data_a": 2, "data_b": "x"}
+    assert yaml.safe_load(parser.dump(cfg))["union"] == value["init_args"]
+
+    value = {"class_path": f"{__name__}.UnionClass", "init_args": {"prm_1": 1.2, "prm_2": False}}
+    cfg = parser.parse_args([f"--union={json.dumps(value)}"])
+    init = parser.instantiate_classes(cfg)
+    assert isinstance(init.union, UnionClass)
+    assert init.union.prm_1 == 1.2
+    assert yaml.safe_load(parser.dump(cfg))["union"] == value
+
+
 # final classes tests