From 97396c615d429c1593370d54b5247278755ff325 Mon Sep 17 00:00:00 2001
From: Caleb Johnson <me@calebj.io>
Date: Wed, 15 Oct 2025 00:45:47 -0500
Subject: [PATCH 1/2] Fix structuring of nested generics, add test

---
 src/cattrs/converters.py      |  5 +++--
 tests/test_generics_nested.py | 24 ++++++++++++++++++++++++
 2 files changed, 27 insertions(+), 2 deletions(-)
 create mode 100644 tests/test_generics_nested.py

diff --git a/src/cattrs/converters.py b/src/cattrs/converters.py
index 08d7fc56..13f63ee1 100644
--- a/src/cattrs/converters.py
+++ b/src/cattrs/converters.py
@@ -1303,10 +1303,11 @@ def gen_structure_typeddict(self, cl: Any) -> Callable[[dict, Any], dict]:
     def gen_structure_attrs_fromdict(
         self, cl: type[T]
     ) -> Callable[[Mapping[str, Any], Any], T]:
-        attribs = fields(get_origin(cl) or cl if is_generic(cl) else cl)
+        origin = get_origin(cl)
+        attribs = fields(origin or cl if is_generic(cl) else cl)
         if attrs_has(cl) and any(isinstance(a.type, str) for a in attribs):
             # PEP 563 annotations - need to be resolved.
-            resolve_types(cl)
+            resolve_types(origin or cl)
         attrib_overrides = {
             a.name: self.type_overrides[a.type]
             for a in attribs
diff --git a/tests/test_generics_nested.py b/tests/test_generics_nested.py
new file mode 100644
index 00000000..a98cc8c1
--- /dev/null
+++ b/tests/test_generics_nested.py
@@ -0,0 +1,24 @@
+"""Tests un/structure of nested generics"""
+
+from __future__ import annotations
+
+from typing import Generic, TypeVar
+
+from attrs import define
+
+T = TypeVar('T')
+
+
+def test_structure_nested_roundtrip(genconverter):
+    @define(auto_attribs=True)
+    class Inner:
+        value: int
+
+    @define(auto_attribs=True)
+    class Container(Generic[T]):
+        data: T
+
+
+    raw = {'data': {'value': 42}}
+    structured = genconverter.structure(raw, Container[Inner])
+    assert genconverter.unstructure(structured, Container[Inner]) == raw

From 0d095603c208cf014bcc5334a9272474e863676d Mon Sep 17 00:00:00 2001
From: Caleb Johnson <me@calebj.io>
Date: Wed, 15 Oct 2025 08:39:33 -0500
Subject: [PATCH 2/2] Black lint, changelog entry, better test docstring

---
 HISTORY.md                    | 5 +++++
 tests/test_generics_nested.py | 7 +++----
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/HISTORY.md b/HISTORY.md
index 4768967a..2eed1dce 100644
--- a/HISTORY.md
+++ b/HISTORY.md
@@ -11,6 +11,11 @@ The third number is for emergencies when we need to start branches for older rel
 
 Our backwards-compatibility policy can be found [here](https://github.com/python-attrs/cattrs/blob/main/.github/SECURITY.md).
 
+## 25.4.0 (UNRELEASED)
+
+- Fix structuring of nested generic classes with stringified annotations.
+  ([#688](https://github.com/python-attrs/cattrs/pull/688))
+
 ## 25.3.0 (2025-10-07)
 
 - **Potentially breaking**: [Abstract sets](https://docs.python.org/3/library/collections.abc.html#collections.abc.Set) are now structured into frozensets.
diff --git a/tests/test_generics_nested.py b/tests/test_generics_nested.py
index a98cc8c1..1e0da3a8 100644
--- a/tests/test_generics_nested.py
+++ b/tests/test_generics_nested.py
@@ -1,4 +1,4 @@
-"""Tests un/structure of nested generics"""
+"""Tests un/structure of nested generic classes (stringified only)"""
 
 from __future__ import annotations
 
@@ -6,7 +6,7 @@
 
 from attrs import define
 
-T = TypeVar('T')
+T = TypeVar("T")
 
 
 def test_structure_nested_roundtrip(genconverter):
@@ -18,7 +18,6 @@ class Inner:
     class Container(Generic[T]):
         data: T
 
-
-    raw = {'data': {'value': 42}}
+    raw = {"data": {"value": 42}}
     structured = genconverter.structure(raw, Container[Inner])
     assert genconverter.unstructure(structured, Container[Inner]) == raw