CookieJar - return 'best-match' and not LIFO (#7577) (#7588)

Co-authored-by: marq24 <marq24@emac.de>
(cherry picked from commit 9c932f7)

Co-authored-by: Matthias Marquardt <marquardt24@gmail.com>

CHANGES/7577.bugfix

@@ -0,0 +1 @@
+Fix sorting in filter_cookies to use cookie with longest path -- by :user:`marq24`.

CONTRIBUTORS.txt

@@ -211,6 +211,7 @@ Martin Melka
 Martin Richard
 Mathias Fröjdman
 Mathieu Dugré
+Matthias Marquardt
 Matthieu Hauglustaine
 Matthieu Rigal
 Meet Mangukiya

aiohttp/cookiejar.py

@@ -251,7 +251,8 @@ def filter_cookies(
             and request_origin not in self._treat_as_secure_origin
         )
 
-        for cookie in self:
+        # Point 2: https://www.rfc-editor.org/rfc/rfc6265.html#section-5.4
+        for cookie in sorted(self, key=lambda c: len(c["path"])):
             name = cookie.key
             domain = cookie["domain"]
 

tests/test_cookiejar.py

@@ -686,6 +686,34 @@ async def make_jar():
         self.assertEqual(len(jar_filtered), 1)
         self.assertEqual(jar_filtered["path-cookie"].value, "one")
 
+    def test_filter_cookies_order_by_path(self) -> None:
+        async def make_jar():
+            return CookieJar(unsafe=True)
+
+        jar = self.loop.run_until_complete(make_jar())
+        jar.update_cookies(
+            SimpleCookie("path-cookie=one; Domain=pathtest.com; Path=/one; ")
+        )
+        jar.update_cookies(
+            SimpleCookie("path-cookie=zero; Domain=pathtest.com; Path=/; ")
+        )
+        jar.update_cookies(
+            SimpleCookie("path-cookie=two; Domain=pathtest.com; Path=/second; ")
+        )
+        self.assertEqual(len(jar), 3)
+
+        jar_filtered = jar.filter_cookies(URL("http://pathtest.com/"))
+        self.assertEqual(len(jar_filtered), 1)
+        self.assertEqual(jar_filtered["path-cookie"].value, "zero")
+
+        jar_filtered = jar.filter_cookies(URL("http://pathtest.com/second"))
+        self.assertEqual(len(jar_filtered), 1)
+        self.assertEqual(jar_filtered["path-cookie"].value, "two")
+
+        jar_filtered = jar.filter_cookies(URL("http://pathtest.com/one"))
+        self.assertEqual(len(jar_filtered), 1)
+        self.assertEqual(jar_filtered["path-cookie"].value, "one")
+
 
 async def test_dummy_cookie_jar() -> None:
     cookie = SimpleCookie("foo=bar; Domain=example.com;")