release: 1.30.2 (#665)

* chore(package): mark python 3.13 as supported

* fix(parsing): correctly handle nested discriminated unions

* release: 1.30.2

---------

Co-authored-by: stainless-app[bot] <142633134+stainless-app[bot]@users.noreply.github.com>

Author: stainless-app[bot]

.release-please-manifest.json

@@ -1,3 +1,3 @@
 {
-  ".": "1.30.1"
+  ".": "1.30.2"
 }

CHANGELOG.md

@@ -1,5 +1,18 @@
 # Changelog
 
+## 1.30.2 (2025-07-09)
+
+Full Changelog: [v1.30.1...v1.30.2](https://github.com/Finch-API/finch-api-python/compare/v1.30.1...v1.30.2)
+
+### Bug Fixes
+
+* **parsing:** correctly handle nested discriminated unions ([28bdcad](https://github.com/Finch-API/finch-api-python/commit/28bdcad5d94a336a9585c1ba646feee058143d88))
+
+
+### Chores
+
+* **package:** mark python 3.13 as supported ([837dbdf](https://github.com/Finch-API/finch-api-python/commit/837dbdf09c38f2472a3fcdab561a2a378c715ad8))
+
 ## 1.30.1 (2025-07-08)
 
 Full Changelog: [v1.30.0...v1.30.1](https://github.com/Finch-API/finch-api-python/compare/v1.30.0...v1.30.1)

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "finch-api"
-version = "1.30.1"
+version = "1.30.2"
 description = "The official Python library for the Finch API"
 dynamic = ["readme"]
 license = "Apache-2.0"
@@ -24,6 +24,7 @@ classifiers = [
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
   "Programming Language :: Python :: 3.12",
+  "Programming Language :: Python :: 3.13",
   "Operating System :: OS Independent",
   "Operating System :: POSIX",
   "Operating System :: MacOS",

src/finch/_models.py

@@ -2,9 +2,10 @@
 
 import os
 import inspect
-from typing import TYPE_CHECKING, Any, Type, Union, Generic, TypeVar, Callable, cast
+from typing import TYPE_CHECKING, Any, Type, Union, Generic, TypeVar, Callable, Optional, cast
 from datetime import date, datetime
 from typing_extensions import (
+    List,
     Unpack,
     Literal,
     ClassVar,
@@ -366,7 +367,7 @@ def _construct_field(value: object, field: FieldInfo, key: str) -> object:
     if type_ is None:
         raise RuntimeError(f"Unexpected field type is None for {key}")
 
-    return construct_type(value=value, type_=type_)
+    return construct_type(value=value, type_=type_, metadata=getattr(field, "metadata", None))
 
 
 def is_basemodel(type_: type) -> bool:
@@ -420,7 +421,7 @@ def construct_type_unchecked(*, value: object, type_: type[_T]) -> _T:
     return cast(_T, construct_type(value=value, type_=type_))
 
 
-def construct_type(*, value: object, type_: object) -> object:
+def construct_type(*, value: object, type_: object, metadata: Optional[List[Any]] = None) -> object:
     """Loose coercion to the expected type with construction of nested values.
 
     If the given value does not match the expected type then it is returned as-is.
@@ -438,8 +439,10 @@ def construct_type(*, value: object, type_: object) -> object:
         type_ = type_.__value__  # type: ignore[unreachable]
 
     # unwrap `Annotated[T, ...]` -> `T`
-    if is_annotated_type(type_):
-        meta: tuple[Any, ...] = get_args(type_)[1:]
+    if metadata is not None:
+        meta: tuple[Any, ...] = tuple(metadata)
+    elif is_annotated_type(type_):
+        meta = get_args(type_)[1:]
         type_ = extract_type_arg(type_, 0)
     else:
         meta = tuple()

src/finch/_version.py

@@ -1,4 +1,4 @@
 # File generated from our OpenAPI spec by Stainless. See CONTRIBUTING.md for details.
 
 __title__ = "finch"
-__version__ = "1.30.1"  # x-release-please-version
+__version__ = "1.30.2"  # x-release-please-version

tests/test_models.py

@@ -889,3 +889,48 @@ class ModelB(BaseModel):
     )
 
     assert isinstance(m, ModelB)
+
+
+def test_nested_discriminated_union() -> None:
+    class InnerType1(BaseModel):
+        type: Literal["type_1"]
+
+    class InnerModel(BaseModel):
+        inner_value: str
+
+    class InnerType2(BaseModel):
+        type: Literal["type_2"]
+        some_inner_model: InnerModel
+
+    class Type1(BaseModel):
+        base_type: Literal["base_type_1"]
+        value: Annotated[
+            Union[
+                InnerType1,
+                InnerType2,
+            ],
+            PropertyInfo(discriminator="type"),
+        ]
+
+    class Type2(BaseModel):
+        base_type: Literal["base_type_2"]
+
+    T = Annotated[
+        Union[
+            Type1,
+            Type2,
+        ],
+        PropertyInfo(discriminator="base_type"),
+    ]
+
+    model = construct_type(
+        type_=T,
+        value={
+            "base_type": "base_type_1",
+            "value": {
+                "type": "type_2",
+            },
+        },
+    )
+    assert isinstance(model, Type1)
+    assert isinstance(model.value, InnerType2)