tests for boundary conditions on redirect_count in fetch

components/net/fetch/methods.rs

@@ -298,7 +298,7 @@ fn http_fetch(request: Rc<Request>,
             };
 
             // Step 7
-            if request.redirect_count.get() == 20 {
+            if request.redirect_count.get() >= 20 {
                 return Response::network_error();
             }
 

tests/unit/net/fetch.rs

@@ -2,19 +2,20 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use hyper::server::{Listening, Server};
+use hyper::header::{Location};
+use hyper::server::{Handler, Listening, Server};
 use hyper::server::{Request as HyperRequest, Response as HyperResponse};
+use hyper::status::StatusCode;
+use hyper::uri::RequestUri;
 use net::fetch::methods::fetch;
 use net_traits::request::{Context, Referer, Request};
 use net_traits::response::{Response, ResponseBody};
 use std::rc::Rc;
 use url::Url;
 
-fn make_server(message: &'static [u8]) -> (Listening, Url) {
+// TODO write a struct that impls Handler for storing test values
 
-    let handler = move |_: HyperRequest, response: HyperResponse| {
-        response.send(message).unwrap();
-    };
+fn make_server<H: Handler + 'static>(handler: H) -> (Listening, Url) {
 
     // this is a Listening server because of handle_threads()
     let server = Server::http("0.0.0.0:0").unwrap().handle_threads(handler, 1).unwrap();
@@ -29,7 +30,10 @@ fn make_server(message: &'static [u8]) -> (Listening, Url) {
 fn test_fetch_response_is_not_network_error() {
 
     static MESSAGE: &'static [u8] = b"";
-    let (mut server, url) = make_server(MESSAGE);
+    let handler = move |_: HyperRequest, response: HyperResponse| {
+        response.send(MESSAGE).unwrap();
+    };
+    let (mut server, url) = make_server(handler);
 
     let mut request = Request::new(url, Context::Fetch, false);
     request.referer = Referer::NoReferer;
@@ -47,7 +51,10 @@ fn test_fetch_response_is_not_network_error() {
 fn test_fetch_response_body_matches_const_message() {
 
     static MESSAGE: &'static [u8] = b"Hello World!";
-    let (mut server, url) = make_server(MESSAGE);
+    let handler = move |_: HyperRequest, response: HyperResponse| {
+        response.send(MESSAGE).unwrap();
+    };
+    let (mut server, url) = make_server(handler);
 
     let mut request = Request::new(url, Context::Fetch, false);
     request.referer = Referer::NoReferer;
@@ -60,6 +67,72 @@ fn test_fetch_response_body_matches_const_message() {
         ResponseBody::Done(body) => {
             assert_eq!(body, MESSAGE);
         },
-        _ => { panic!() }
+        _ => panic!()
+    };
+}
+
+fn test_fetch_redirect_count(message: &'static [u8], redirect_cap: u32) -> Response {
+
+    let handler = move |request: HyperRequest, mut response: HyperResponse| {
+
+        let redirects = match request.uri {
+            RequestUri::AbsolutePath(url) =>
+                url.split("/").collect::<String>().parse::<u32>().unwrap_or(0),
+            RequestUri::AbsoluteUri(url) =>
+                url.path().unwrap().last().unwrap().split("/").collect::<String>().parse::<u32>().unwrap_or(0),
+            _ => panic!()
+        };
+
+        if redirects >= redirect_cap {
+            response.send(message).unwrap();
+        } else {
+            *response.status_mut() = StatusCode::Found;
+            let url = format!("{redirects}", redirects = redirects + 1);
+            response.headers_mut().set(Location(url.to_owned()));
+        }
+    };
+
+    let (mut server, url) = make_server(handler);
+
+    let mut request = Request::new(url, Context::Fetch, false);
+    request.referer = Referer::NoReferer;
+    let wrapped_request = Rc::new(request);
+
+    let fetch_response = fetch(wrapped_request, false);
+    let _ = server.close();
+    fetch_response
+}
+
+#[test]
+fn test_fetch_redirect_count_ceiling() {
+
+    static MESSAGE: &'static [u8] = b"no more redirects";
+    // how many redirects to cause
+    let redirect_cap = 20;
+
+    let fetch_response = test_fetch_redirect_count(MESSAGE, redirect_cap);
+
+    assert_eq!(Response::is_network_error(&fetch_response), false);
+    match fetch_response.body {
+        ResponseBody::Done(body) => {
+            assert_eq!(body, MESSAGE);
+        },
+        _ => panic!()
+    };
+}
+
+#[test]
+fn test_fetch_redirect_count_failure() {
+
+    static MESSAGE: &'static [u8] = b"this message shouldn't be reachable";
+    // how many redirects to cause
+    let redirect_cap = 21;
+
+    let fetch_response = test_fetch_redirect_count(MESSAGE, redirect_cap);
+
+    assert_eq!(Response::is_network_error(&fetch_response), true);
+    match fetch_response.body {
+        ResponseBody::Done(_) => panic!(),
+        _ => { }
     };
 }