Include new cookie header after a redirect (#514)

Closes #510

tests/redirect.rs

@@ -387,3 +387,56 @@ fn test_invalid_location_stops_redirect_gh484() {
     assert_eq!(res.status(), reqwest::StatusCode::FOUND);
     assert_eq!(res.headers().get(reqwest::header::SERVER).unwrap(), &"test-yikes");
 }
+
+#[test]
+fn test_redirect_302_with_set_cookies() {
+    let code = 302;
+    let client = reqwest::ClientBuilder::new().cookie_store(true).build().unwrap();
+    let server = server! {
+            request: format!("\
+                GET /{} HTTP/1.1\r\n\
+                user-agent: $USERAGENT\r\n\
+                accept: */*\r\n\
+                accept-encoding: gzip\r\n\
+                host: $HOST\r\n\
+                \r\n\
+                ", code),
+            response: format!("\
+                HTTP/1.1 {} reason\r\n\
+                Server: test-redirect\r\n\
+                Content-Length: 0\r\n\
+                Location: /dst\r\n\
+                Connection: close\r\n\
+                Set-Cookie: key=value\r\n\
+                \r\n\
+                ", code)
+                ;
+
+            request: format!("\
+                GET /dst HTTP/1.1\r\n\
+                user-agent: $USERAGENT\r\n\
+                accept: */*\r\n\
+                accept-encoding: gzip\r\n\
+                referer: http://$HOST/{}\r\n\
+                cookie: key=value\r\n\
+                host: $HOST\r\n\
+                \r\n\
+                ", code),
+            response: b"\
+                HTTP/1.1 200 OK\r\n\
+                Server: test-dst\r\n\
+                Content-Length: 0\r\n\
+                \r\n\
+                "
+        };
+
+    let url = format!("http://{}/{}", server.addr(), code);
+    let dst = format!("http://{}/{}", server.addr(), "dst");
+    let res = client.get(&url)
+        .send()
+        .unwrap();
+
+    assert_eq!(res.url().as_str(), dst);
+    assert_eq!(res.status(), reqwest::StatusCode::OK);
+    assert_eq!(res.headers().get(reqwest::header::SERVER).unwrap(), &"test-dst");
+}