[rh:urllib] Fix relative redirects with dot segments (#17712)

Authored by: doe1080

test/test_networking.py

@@ -180,6 +180,11 @@ class HTTPTestRequestHandler(http.server.BaseHTTPRequestHandler):
             self.send_header('Location', '/a/b/./../../headers')
             self.send_header('Content-Length', '0')
             self.end_headers()
+        elif self.path == '/a/b/redirect_relative_dotsegments':
+            self.send_response(301)
+            self.send_header('Location', '../../headers')
+            self.send_header('Content-Length', '0')
+            self.end_headers()
         elif self.path == '/redirect_dotsegments_absolute':
             self.send_response(301)
             # redirect to /headers but with dot segments before - absolute url
@@ -412,6 +417,7 @@ class TestHTTPRequestHandler(TestRequestHandlerBase):
     @pytest.mark.parametrize('path', [
         '/a/b/./../../headers',
         '/redirect_dotsegments',
+        '/a/b/redirect_relative_dotsegments',
         # https://github.com/yt-dlp/yt-dlp/issues/9020
         '/redirect_dotsegments_absolute',
     ])

yt_dlp/networking/_urllib.py

@@ -161,17 +161,7 @@ class HTTPHandler(urllib.request.AbstractHTTPHandler):
         if decoded_response is not None:
             resp = urllib.request.addinfourl(io.BytesIO(decoded_response), old_resp.headers, old_resp.url, old_resp.code)
             resp.msg = old_resp.msg
-        # Percent-encode redirect URL of Location HTTP header to satisfy RFC 3986 (see
-        # https://github.com/ytdl-org/youtube-dl/issues/6457).
-        if 300 <= resp.code < 400:
-            location = resp.headers.get('Location')
-            if location:
-                # As of RFC 2616 default charset is iso-8859-1 that is respected by Python 3
-                location = location.encode('iso-8859-1').decode()
-                location_escaped = normalize_url(location)
-                if location != location_escaped:
-                    del resp.headers['Location']
-                    resp.headers['Location'] = location_escaped
+
         return resp
 
     https_request = http_request