Fix get_raw_segments index argument in route codegen.

Fixes #41.

codegen/src/decorators/route.rs

@@ -15,6 +15,7 @@ use syntax::parse::token;
 use syntax::ptr::P;
 
 use rocket::http::{Method, ContentType};
+use rocket::http::uri::URI;
 
 fn method_to_path(ecx: &ExtCtxt, method: Method) -> Path {
     quote_enum!(ecx, method => ::rocket::http::Method {
@@ -136,10 +137,18 @@ impl RouteGenerateExt for RouteParams {
                     Some(s) => <$ty as ::rocket::request::FromParam>::from_param(s),
                     None => return ::rocket::Outcome::Forward(_data)
                 }),
-                Param::Many(_) => quote_expr!(ecx, match _req.get_raw_segments($i) {
-                    Some(s) => <$ty as ::rocket::request::FromSegments>::from_segments(s),
-                    None => return ::rocket::Outcome::forward(_data)
-                }),
+                Param::Many(_) => {
+                    // Determine the index the dynamic segments parameter begins.
+                    let d = URI::new(self.path.node.as_str()).segments().enumerate()
+                        .filter(|&(_, s)| s.starts_with("<"))
+                        .map((&|(d, _)| d))
+                        .next().expect("segment when segment is iterated");
+
+                    quote_expr!(ecx, match _req.get_raw_segments($d) {
+                        Some(s) => <$ty as ::rocket::request::FromSegments>::from_segments(s),
+                        None => return ::rocket::Outcome::forward(_data)
+                    })
+                },
             };
 
             let original_ident = param.ident();

lib/tests/segments-issue-41.rs

@@ -0,0 +1,45 @@
+#![feature(plugin)]
+#![plugin(rocket_codegen)]
+
+extern crate rocket;
+
+use std::path::PathBuf;
+
+#[get("/test/<path..>")]
+fn test(path: PathBuf) -> String {
+    format!("{:?}", path)
+}
+
+#[get("/two/<path..>")]
+fn two(path: PathBuf) -> String {
+    format!("{:?}", path)
+}
+
+#[get("/one/two/<path..>")]
+fn one_two(path: PathBuf) -> String {
+    format!("{:?}", path)
+}
+
+#[get("/<path..>", rank = 2)]
+fn none(path: PathBuf) -> String {
+    format!("{:?}", path)
+}
+
+use rocket::testing::MockRequest;
+use rocket::http::Method::*;
+
+#[test]
+fn segments_works() {
+    let rocket = rocket::ignite().mount("/", routes![test, two, one_two, none]);
+
+    // We construct a path that matches each of the routes above. We ensure the
+    // prefix is stripped, confirming that dynamic segments are working.
+    for prefix in &["", "/test", "/two", "/one/two"] {
+        let path = "this/is/the/path/we/want";
+        let mut req = MockRequest::new(Get, format!("{}/{}", prefix, path));
+
+        let mut response = req.dispatch_with(&rocket);
+        let body_str = response.body().and_then(|b| b.into_string());
+        assert_eq!(body_str, Some(format!("{:?}", path)));
+    }
+}