Auto merge of #8752 - Manishearth:om-nom, r=metajack

Make `path_matches` match the spec (fixes cookies)

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components/net/cookie.rs

@@ -113,10 +113,21 @@ impl Cookie {
 
     // http://tools.ietf.org/html/rfc6265#section-5.1.4
     pub fn path_match(request_path: &str, cookie_path: &str) -> bool {
+        // A request-path path-matches a given cookie-path if at least one of
+        // the following conditions holds:
+
+        // The cookie-path and the request-path are identical.
         request_path == cookie_path ||
-        ( request_path.starts_with(cookie_path) &&
-            ( request_path.ends_with("/") || request_path[cookie_path.len()..].starts_with("/"))
-        )
+
+        (request_path.starts_with(cookie_path) && (
+            // The cookie-path is a prefix of the request-path, and the last
+            // character of the cookie-path is %x2F ("/").
+            cookie_path.ends_with("/") ||
+            // The cookie-path is a prefix of the request-path, and the first
+            // character of the request-path that is not included in the cookie-
+            // path is a %x2F ("/") character.
+            request_path[cookie_path.len()..].starts_with("/")
+        ))
     }
 
     // http://tools.ietf.org/html/rfc6265#section-5.1.3

tests/unit/net/cookie.rs

@@ -25,6 +25,23 @@ fn test_domain_match() {
     assert!(!Cookie::domain_match("235.132.2.3", ".2.3"));
 }
 
+#[test]
+fn test_path_match() {
+    assert!(Cookie::path_match("/", "/"));
+    assert!(Cookie::path_match("/index.html", "/"));
+    assert!(Cookie::path_match("/w/index.html", "/"));
+    assert!(Cookie::path_match("/w/index.html", "/w/index.html"));
+    assert!(Cookie::path_match("/w/index.html", "/w/"));
+    assert!(Cookie::path_match("/w/index.html", "/w"));
+
+    assert!(!Cookie::path_match("/", "/w/"));
+    assert!(!Cookie::path_match("/a", "/w/"));
+    assert!(!Cookie::path_match("/", "/w"));
+    assert!(!Cookie::path_match("/w/index.html", "/w/index"));
+    assert!(!Cookie::path_match("/windex.html", "/w/"));
+    assert!(!Cookie::path_match("/windex.html", "/w"));
+}
+
 #[test]
 fn test_default_path() {
     assert!(&*Cookie::default_path("/foo/bar/baz/") == "/foo/bar/baz");