Added support for navigating by a delta

components/compositing/compositor.rs

@@ -1803,8 +1803,8 @@ impl<Window: WindowMethods> IOCompositor<Window> {
 
     fn on_navigation_window_event(&self, direction: WindowNavigateMsg) {
         let direction = match direction {
-            windowing::WindowNavigateMsg::Forward => NavigationDirection::Forward,
-            windowing::WindowNavigateMsg::Back => NavigationDirection::Back,
+            windowing::WindowNavigateMsg::Forward => NavigationDirection::Forward(1),
+            windowing::WindowNavigateMsg::Back => NavigationDirection::Back(1),
         };
         let msg = ConstellationMsg::Navigate(None, direction);
         if let Err(e) = self.constellation_chan.send(msg) {

components/constellation/constellation.rs

@@ -1278,33 +1278,49 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
         // Get the ids for the previous and next pipelines.
         let (prev_pipeline_id, next_pipeline_id) = match self.frames.get_mut(&frame_id) {
             Some(frame) => {
+                let prev = frame.current;
                 let next = match direction {
-                    NavigationDirection::Forward => {
-                        match frame.next.pop() {
-                            None => {
-                                warn!("no next page to navigate to");
-                                return;
-                            },
-                            Some(next) => {
-                                frame.prev.push(frame.current);
-                                next
-                            },
+                    NavigationDirection::Forward(delta) => {
+                        if frame.next.len() < delta {
+                            return warn!("Invalid navigation delta");
+                        }
+                        let mut new_current = frame.current;
+                        for _ in 0..delta {
+                            match frame.next.pop() {
+                                None => {
+                                    warn!("no next page to navigate to");
+                                    return;
+                                },
+                                Some(next) => {
+                                    frame.prev.push(frame.current);
+                                    frame.current = next;
+                                    new_current = next;
+                                },
+                            }
                         }
+                        new_current
                     }
-                    NavigationDirection::Back => {
-                        match frame.prev.pop() {
-                            None => {
-                                warn!("no previous page to navigate to");
-                                return;
-                            },
-                            Some(prev) => {
-                                frame.next.push(frame.current);
-                                prev
-                            },
+                    NavigationDirection::Back(delta) => {
+                        if frame.prev.len() < delta {
+                            return warn!("Invalid navigation delta");
                         }
+                        let mut new_current = frame.current;
+                        for _ in 0..delta {
+                            match frame.prev.pop() {
+                                None => {
+                                    warn!("no prev page to navigate to");
+                                    return;
+                                },
+                                Some(prev) => {
+                                    frame.next.push(frame.current);
+                                    frame.current = prev;
+                                    new_current = prev;
+                                },
+                            }
+                        }
+                        new_current
                     }
                 };
-                let prev = frame.current;
                 frame.current = next;
                 (prev, next)
             },

components/msg/constellation_msg.rs

@@ -244,8 +244,8 @@ impl LoadData {
 
 #[derive(Clone, PartialEq, Eq, Copy, Hash, Debug, Deserialize, Serialize)]
 pub enum NavigationDirection {
-    Forward,
-    Back,
+    Forward(usize),
+    Back(usize),
 }
 
 #[derive(Clone, PartialEq, Eq, Copy, Hash, Debug, Deserialize, Serialize)]

components/script/dom/htmliframeelement.rs

@@ -468,12 +468,12 @@ impl HTMLIFrameElementMethods for HTMLIFrameElement {
 
     // https://developer.mozilla.org/en-US/docs/Web/API/HTMLIFrameElement/goBack
     fn GoBack(&self) -> ErrorResult {
-        Navigate(self, NavigationDirection::Back)
+        Navigate(self, NavigationDirection::Back(1))
     }
 
     // https://developer.mozilla.org/en-US/docs/Web/API/HTMLIFrameElement/goForward
     fn GoForward(&self) -> ErrorResult {
-        Navigate(self, NavigationDirection::Forward)
+        Navigate(self, NavigationDirection::Forward(1))
     }
 
     // https://developer.mozilla.org/en-US/docs/Web/API/HTMLIFrameElement/reload

components/webdriver_server/lib.rs

@@ -417,12 +417,12 @@ impl Handler {
     }
 
     fn handle_go_back(&self) -> WebDriverResult<WebDriverResponse> {
-        self.constellation_chan.send(ConstellationMsg::Navigate(None, NavigationDirection::Back)).unwrap();
+        self.constellation_chan.send(ConstellationMsg::Navigate(None, NavigationDirection::Back(1))).unwrap();
         Ok(WebDriverResponse::Void)
     }
 
     fn handle_go_forward(&self) -> WebDriverResult<WebDriverResponse> {
-        self.constellation_chan.send(ConstellationMsg::Navigate(None, NavigationDirection::Forward)).unwrap();
+        self.constellation_chan.send(ConstellationMsg::Navigate(None, NavigationDirection::Forward(1))).unwrap();
         Ok(WebDriverResponse::Void)
     }