From 5cacca96aefaadd63ddc2b66b1b86807ff26dcf0 Mon Sep 17 00:00:00 2001
From: "RUANG (James Roy)" <longjinyii@outlook.com>
Date: Sat, 15 Feb 2025 01:26:26 +0800
Subject: [PATCH] gh-128703: Fix mimetypes.guess_type for empty Content-Type in
 registry (GH-128854) (cherry picked from commit
 303043f5062c1e7ffb7907abde61dbf13c98f8e9)

Co-authored-by: RUANG (James Roy) <longjinyii@outlook.com>
---
 Lib/mimetypes.py                                                | 2 ++
 .../next/Library/2025-01-15-12-04-30.gh-issue-128703.6WPf38.rst | 2 ++
 2 files changed, 4 insertions(+)
 create mode 100644 Misc/NEWS.d/next/Library/2025-01-15-12-04-30.gh-issue-128703.6WPf38.rst

diff --git a/Lib/mimetypes.py b/Lib/mimetypes.py
index 10f3ddc5a152f4..64b550b069017b 100644
--- a/Lib/mimetypes.py
+++ b/Lib/mimetypes.py
@@ -95,6 +95,8 @@ def add_type(self, type, ext, strict=True):
         list of standard types, else to the list of non-standard
         types.
         """
+        if not type:
+            return
         self.types_map[strict][ext] = type
         exts = self.types_map_inv[strict].setdefault(type, [])
         if ext not in exts:
diff --git a/Misc/NEWS.d/next/Library/2025-01-15-12-04-30.gh-issue-128703.6WPf38.rst b/Misc/NEWS.d/next/Library/2025-01-15-12-04-30.gh-issue-128703.6WPf38.rst
new file mode 100644
index 00000000000000..1e6af90bc04b63
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-01-15-12-04-30.gh-issue-128703.6WPf38.rst
@@ -0,0 +1,2 @@
+Fix :func:`mimetypes.guess_type` to use default mapping for empty
+``Content-Type`` in registry.