Implement MediaList interface

1 files changed, 18 insertions, 2 deletions

diff --git a/components/script/dom/cssmediarule.rs b/components/script/dom/cssmediarule.rs
index e42c1bc0021..7f4f43f3d5b 100644
--- a/components/script/dom/cssmediarule.rs
+++ b/components/script/dom/cssmediarule.rs
@@ -3,12 +3,14 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use dom::bindings::codegen::Bindings::CSSMediaRuleBinding;
-use dom::bindings::js::Root;
-use dom::bindings::reflector::reflect_dom_object;
+use dom::bindings::codegen::Bindings::CSSMediaRuleBinding::CSSMediaRuleMethods;
+use dom::bindings::js::{JS, MutNullableHeap, Root};
+use dom::bindings::reflector::{Reflectable, reflect_dom_object};
 use dom::bindings::str::DOMString;
 use dom::cssgroupingrule::CSSGroupingRule;
 use dom::cssrule::SpecificCSSRule;
 use dom::cssstylesheet::CSSStyleSheet;
+use dom::medialist::MediaList;
 use dom::window::Window;
 use parking_lot::RwLock;
 use std::sync::Arc;
@@ -20,6 +22,7 @@ pub struct CSSMediaRule {
     cssrule: CSSGroupingRule,
     #[ignore_heap_size_of = "Arc"]
     mediarule: Arc<RwLock<MediaRule>>,
+    medialist: MutNullableHeap<JS<MediaList>>,
 }
 
 impl CSSMediaRule {
@@ -29,6 +32,7 @@ impl CSSMediaRule {
         CSSMediaRule {
             cssrule: CSSGroupingRule::new_inherited(parent_stylesheet, list),
             mediarule: mediarule,
+            medialist: MutNullableHeap::new(None),
         }
     }
 
@@ -39,6 +43,11 @@ impl CSSMediaRule {
                            window,
                            CSSMediaRuleBinding::Wrap)
     }
+
+    fn medialist(&self) -> Root<MediaList> {
+        self.medialist.or_init(|| MediaList::new(self.global().as_window(),
+                                                 self.mediarule.read().media_queries.clone()))
+    }
 }
 
 impl SpecificCSSRule for CSSMediaRule {
@@ -51,3 +60,10 @@ impl SpecificCSSRule for CSSMediaRule {
         self.mediarule.read().to_css_string().into()
     }
 }
+
+impl CSSMediaRuleMethods for CSSMediaRule {
+    // https://drafts.csswg.org/cssom/#dom-cssgroupingrule-media
+    fn Media(&self) -> Root<MediaList> {
+        self.medialist()
+    }
+}