Auto merge of #12552 - ConnorGBrewster:history_interface, r=asajeffrey

History interface Go, Back, and Forward

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r? @asajeffrey

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #5670 (github issue number if applicable).

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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implement go, forward, back

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1 files changed, 70 insertions, 0 deletions

diff --git a/components/script/dom/history.rs b/components/script/dom/history.rs
new file mode 100644
index 00000000000..061d7616f4a
--- /dev/null
+++ b/components/script/dom/history.rs
@@ -0,0 +1,70 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use dom::bindings::codegen::Bindings::HistoryBinding;
+use dom::bindings::codegen::Bindings::HistoryBinding::HistoryMethods;
+use dom::bindings::codegen::Bindings::LocationBinding::LocationMethods;
+use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
+use dom::bindings::global::GlobalRef;
+use dom::bindings::js::{JS, Root};
+use dom::bindings::reflector::{Reflector, reflect_dom_object};
+use dom::window::Window;
+use msg::constellation_msg::TraversalDirection;
+use script_traits::ScriptMsg as ConstellationMsg;
+
+// https://html.spec.whatwg.org/multipage/#the-history-interface
+#[dom_struct]
+pub struct History {
+    reflector_: Reflector,
+    window: JS<Window>,
+}
+
+impl History {
+    pub fn new_inherited(window: &Window) -> History {
+        History {
+            reflector_: Reflector::new(),
+            window: JS::from_ref(&window),
+        }
+    }
+
+    pub fn new(window: &Window) -> Root<History> {
+        reflect_dom_object(box History::new_inherited(window),
+                           GlobalRef::Window(window),
+                           HistoryBinding::Wrap)
+    }
+}
+
+impl History {
+    fn traverse_history(&self, direction: TraversalDirection) {
+        let pipeline = self.window.pipeline();
+        let msg = ConstellationMsg::TraverseHistory(Some(pipeline), direction);
+        let _ = self.window.constellation_chan().send(msg);
+    }
+}
+
+impl HistoryMethods for History {
+    // https://html.spec.whatwg.org/multipage/#dom-history-go
+    fn Go(&self, delta: i32) {
+        let direction = if delta > 0 {
+            TraversalDirection::Forward(delta as usize)
+        } else if delta < 0 {
+            TraversalDirection::Back(-delta as usize)
+        } else {
+            self.window.Location().Reload();
+            return;
+        };
+
+        self.traverse_history(direction);
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-history-back
+    fn Back(&self) {
+        self.traverse_history(TraversalDirection::Back(1));
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-history-forward
+    fn Forward(&self) {
+        self.traverse_history(TraversalDirection::Forward(1));
+    }
+}