[Python-checkins] bpo-20392: Fix inconsistency with uppercase file extensions in mimetypes.guess_type (GH-30229)

Tue Mar 15 09:25:47 EDT 2022

https://github.com/python/cpython/commit/5dd7ec52b83e7f239774cf7478106fcc7b0a36f3
commit: 5dd7ec52b83e7f239774cf7478106fcc7b0a36f3
branch: main
author: Kumar Aditya <59607654+kumaraditya303 at users.noreply.github.com>
committer: asvetlov <andrew.svetlov at gmail.com>
date: 2022年03月15日T15:25:43+02:00
summary:
bpo-20392: Fix inconsistency with uppercase file extensions in mimetypes.guess_type (GH-30229)
files:
A Misc/NEWS.d/next/Library/2021-12-22-12-02-27.bpo-20392.CLAFIp.rst
M Lib/mimetypes.py
M Lib/test/test_mimetypes.py

diff --git a/Lib/mimetypes.py b/Lib/mimetypes.py
index 4750408173ec0..1aa32467e278a 100644
--- a/Lib/mimetypes.py
+++ b/Lib/mimetypes.py
@@ -141,25 +141,23 @@ def guess_type(self, url, strict=True):
 type = 'text/plain'
 return type, None # never compressed, so encoding is None
 base, ext = posixpath.splitext(url)
- while ext in self.suffix_map:
- base, ext = posixpath.splitext(base + self.suffix_map[ext])
+ while (ext_lower := ext.lower()) in self.suffix_map:
+ base, ext = posixpath.splitext(base + self.suffix_map[ext_lower])
+ # encodings_map is case sensitive
 if ext in self.encodings_map:
 encoding = self.encodings_map[ext]
 base, ext = posixpath.splitext(base)
 else:
 encoding = None
+ ext = ext.lower()
 types_map = self.types_map[True]
 if ext in types_map:
 return types_map[ext], encoding
- elif ext.lower() in types_map:
- return types_map[ext.lower()], encoding
 elif strict:
 return None, encoding
 types_map = self.types_map[False]
 if ext in types_map:
 return types_map[ext], encoding
- elif ext.lower() in types_map:
- return types_map[ext.lower()], encoding
 else:
 return None, encoding
 
diff --git a/Lib/test/test_mimetypes.py b/Lib/test/test_mimetypes.py
index 392ddd2d5eee9..3477b18376a4f 100644
--- a/Lib/test/test_mimetypes.py
+++ b/Lib/test/test_mimetypes.py
@@ -33,6 +33,13 @@ def tearDownModule():
 class MimeTypesTestCase(unittest.TestCase):
 def setUp(self):
 self.db = mimetypes.MimeTypes()
+ 
+ def test_case_sensitivity(self):
+ eq = self.assertEqual
+ eq(self.db.guess_type("foobar.HTML"), self.db.guess_type("foobar.html"))
+ eq(self.db.guess_type("foobar.TGZ"), self.db.guess_type("foobar.tgz"))
+ eq(self.db.guess_type("foobar.tar.Z"), ("application/x-tar", "compress"))
+ eq(self.db.guess_type("foobar.tar.z"), (None, None))
 
 def test_default_data(self):
 eq = self.assertEqual
diff --git a/Misc/NEWS.d/next/Library/2021-12-22-12-02-27.bpo-20392.CLAFIp.rst b/Misc/NEWS.d/next/Library/2021-12-22-12-02-27.bpo-20392.CLAFIp.rst
new file mode 100644
index 0000000000000..8973c4d433174
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2021-12-22-12-02-27.bpo-20392.CLAFIp.rst
@@ -0,0 +1 @@
+Fix inconsistency with uppercase file extensions in :meth:`MimeTypes.guess_type`. Patch by Kumar Aditya.
