Don't overwrite catcher response status if it is set.

Resolves #113.

codegen/src/decorators/error.rs

@@ -60,11 +60,10 @@ pub fn error_decorator(ecx: &mut ExtCtxt, sp: Span, meta_item: &MetaItem,
         fn $catch_fn_name<'_b>($err_ident: ::rocket::Error,
                                $req_ident: &'_b ::rocket::Request)
                                -> ::rocket::response::Result<'_b> {
-            let response = $user_fn_name($fn_arguments);
+            let user_response = $user_fn_name($fn_arguments);
+            let response = ::rocket::response::Responder::respond(user_response)?;
             let status = ::rocket::http::Status::raw($code);
-            ::rocket::response::Responder::respond(
-                ::rocket::response::status::Custom(status, response)
-            )
+            ::rocket::response::Response::build().status(status).merge(response).ok()
         }
     ).expect("catch function"));
 

lib/tests/redirect_from_catcher-issue-113.rs

@@ -0,0 +1,31 @@
+#![feature(plugin)]
+#![plugin(rocket_codegen)]
+
+extern crate rocket;
+
+use rocket::response::Redirect;
+
+#[error(404)]
+fn not_found() -> Redirect {
+    Redirect::to("/")
+}
+
+#[cfg(feature = "testing")]
+mod tests {
+    use super::*;
+    use rocket::testing::MockRequest;
+    use rocket::http::Method::*;
+    use rocket::http::Status;
+
+    #[test]
+    fn error_catcher_redirect() {
+        let rocket = rocket::ignite().catch(errors![not_found]);
+        let mut req = MockRequest::new(Get, "/unknown");
+        let response = req.dispatch_with(&rocket);
+        println!("Response:\n{:?}", response);
+
+        let location: Vec<_> = response.header_values("location").collect();
+        assert_eq!(response.status(), Status::SeeOther);
+        assert_eq!(location, vec!["/"]);
+    }
+}