Fix dict value unstructuring (#462)

* Fix dict value unstructuring

* Update HISTORY

Author: Tinche

HISTORY.md

@@ -1,10 +1,16 @@
 # History
 
+## 23.2.3 (UNRELEASED)
+
+- Fix a regression when unstructuring dictionary values typed as `Any`.
+  ([#453](https://github.com/python-attrs/cattrs/issues/453) [#462](https://github.com/python-attrs/cattrs/pull/462))
+- Generate unique files only in case of linecache enabled.
+  ([#445](https://github.com/python-attrs/cattrs/issues/445) [#441](https://github.com/python-attrs/cattrs/pull/461))
+
 ## 23.2.2 (2023-11-21)
 
 - Fix a regression when unstructuring `Any | None`.
-  ([#453](https://github.com/python-attrs/cattrs/issues/453))
-- Generate unique files only in case of linecache enabled. ([#445](https://github.com/python-attrs/cattrs/issues/445) [#441](https://github.com/python-attrs/cattrs/pull/461))
+  ([#453](https://github.com/python-attrs/cattrs/issues/453) [#454](https://github.com/python-attrs/cattrs/pull/454))
 
 ## 23.2.1 (2023-11-18)
 

src/cattrs/gen/__init__.py

@@ -743,9 +743,11 @@ def make_mapping_unstructure_fn(
         if kh == identity:
             kh = None
 
-        val_handler = converter._unstructure_func.dispatch(val_arg)
-        if val_handler == identity:
-            val_handler = None
+        if val_arg is not Any:
+            # TODO: Remove this once we have more consistent Any handling in place.
+            val_handler = converter._unstructure_func.dispatch(val_arg)
+            if val_handler == identity:
+                val_handler = None
 
     globs = {
         "__cattr_mapping_cl": unstructure_to or cl,

tests/test_any.py

@@ -0,0 +1,14 @@
+"""Tests for handling `typing.Any`."""
+from typing import Any, Dict
+
+from attrs import define
+
+
+@define
+class A:
+    pass
+
+
+def test_unstructuring_dict_of_any(converter):
+    """Dicts with Any values should use runtime dispatch for their values."""
+    assert converter.unstructure({"a": A()}, Dict[str, Any]) == {"a": {}}