Only override request methods via '_method' on POST.

lib/src/rocket.rs

@@ -141,7 +141,7 @@ impl Rocket {
         // field which we use to reinterpret the request's method.
         let data_len = data.peek().len();
         let (min_len, max_len) = ("_method=get".len(), "_method=delete".len());
-        if req.content_type().is_form() && data_len >= min_len {
+        if req.method() == Method::Post && req.content_type().is_form() && data_len >= min_len {
             let form = unsafe {
                 from_utf8_unchecked(&data.peek()[..min(data_len, max_len)])
             };

lib/tests/form_method-issue-45.rs

@@ -4,6 +4,7 @@
 extern crate rocket;
 
 use rocket::request::Form;
+use rocket::http::Status;
 
 #[derive(FromForm)]
 struct FormData {
@@ -24,7 +25,7 @@ use rocket::http::ContentType;
 fn method_eval() {
     let rocket = rocket::ignite().mount("/", routes![bug]);
 
-    let mut req = MockRequest::new(Patch, "/")
+    let mut req = MockRequest::new(Post, "/")
         .header(ContentType::Form)
         .body("_method=patch&form_data=Form+data");
 
@@ -32,3 +33,15 @@ fn method_eval() {
     let body_str = response.body().and_then(|b| b.into_string());
     assert_eq!(body_str, Some("OK".to_string()));
 }
+
+#[test]
+fn get_passes_through() {
+    let rocket = rocket::ignite().mount("/", routes![bug]);
+
+    let mut req = MockRequest::new(Get, "/")
+        .header(ContentType::Form)
+        .body("_method=patch&form_data=Form+data");
+
+    let mut response = req.dispatch_with(&rocket);
+    assert_eq!(response.status(), Status::NotFound);
+}