From 4970f5d6590cda345ee286ced85871532aa27846 Mon Sep 17 00:00:00 2001
From: AlexWaygood <alex.waygood@gmail.com>
Date: Wed, 10 May 2023 19:36:05 +0100
Subject: [PATCH 1/3] Optimise `dataclasses.asdict` for the common case

Co-authored-by: David Ellis <ducksual@gmail.com>
---
 Lib/dataclasses.py                              | 17 ++++++++++++-----
 ...23-05-10-19-33-36.gh-issue-103000.j0KSfD.rst |  2 ++
 2 files changed, 14 insertions(+), 5 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst

diff --git a/Lib/dataclasses.py b/Lib/dataclasses.py
index b0b8a773b7594f..3eacba840db426 100644
--- a/Lib/dataclasses.py
+++ b/Lib/dataclasses.py
@@ -1324,11 +1324,18 @@ def _asdict_inner(obj, dict_factory):
     if type(obj) in _ATOMIC_TYPES:
         return obj
     elif _is_dataclass_instance(obj):
-        result = []
-        for f in fields(obj):
-            value = _asdict_inner(getattr(obj, f.name), dict_factory)
-            result.append((f.name, value))
-        return dict_factory(result)
+        # fast path for the common case
+        if dict_factory is dict:
+            return {
+                f.name: _asdict_inner(getattr(obj, f.name), dict)
+                for f in fields(obj)
+            }
+        else:
+            result = []
+            for f in fields(obj):
+                value = _asdict_inner(getattr(obj, f.name), dict_factory)
+                result.append((f.name, value))
+            return dict_factory(result)
     elif isinstance(obj, tuple) and hasattr(obj, '_fields'):
         # obj is a namedtuple.  Recurse into it, but the returned
         # object is another namedtuple of the same type.  This is
diff --git a/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst b/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst
new file mode 100644
index 00000000000000..e88481495c2208
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst
@@ -0,0 +1,2 @@
+Improve performance of :func:`dataclasses.asdict` for the common case where
+`dict_factory` is `dict`.

From 29231d5a6537a499e605f497754d55b074c2a0d3 Mon Sep 17 00:00:00 2001
From: Alex Waygood <Alex.Waygood@Gmail.com>
Date: Wed, 10 May 2023 19:45:15 +0100
Subject: [PATCH 2/3] Update 2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst

---
 .../next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst b/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst
index e88481495c2208..aeaba2b55e5661 100644
--- a/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst
+++ b/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst
@@ -1,2 +1,2 @@
 Improve performance of :func:`dataclasses.asdict` for the common case where
-`dict_factory` is `dict`.
+`dict_factory` is `dict`. Patch by David C Ellis.

From 4e01d46cfaf9c797a940efc48c29db11a1bf7fcd Mon Sep 17 00:00:00 2001
From: Alex Waygood <Alex.Waygood@Gmail.com>
Date: Wed, 10 May 2023 19:48:02 +0100
Subject: [PATCH 3/3] this isn't markdown

---
 .../next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst b/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst
index aeaba2b55e5661..f84ec5c8b3caf6 100644
--- a/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst
+++ b/Misc/NEWS.d/next/Library/2023-05-10-19-33-36.gh-issue-103000.j0KSfD.rst
@@ -1,2 +1,2 @@
 Improve performance of :func:`dataclasses.asdict` for the common case where
-`dict_factory` is `dict`. Patch by David C Ellis.
+*dict_factory* is ``dict``. Patch by David C Ellis.