4 files changed, 50 insertions, 12 deletions
diff --git a/components/script/dom/url.rs b/components/script/dom/url.rs
index adc758a8f18..06e1af5b133 100644
--- a/components/script/dom/url.rs
+++ b/components/script/dom/url.rs
@@ -6,11 +6,13 @@ use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::URLBinding::{self, URLMethods};
 use dom::bindings::error::{Error, ErrorResult, Fallible};
 use dom::bindings::global::GlobalRef;
-use dom::bindings::js::Root;
-use dom::bindings::reflector::{Reflector, reflect_dom_object};
+use dom::bindings::js::{JS, MutNullableHeap, Root};
+use dom::bindings::reflector::{Reflectable, Reflector, reflect_dom_object};
 use dom::bindings::str::USVString;
 use dom::urlhelper::UrlHelper;
+use dom::urlsearchparams::URLSearchParams;
 use std::borrow::ToOwned;
+use std::default::Default;
 use url::{Host, ParseResult, Url, UrlParser};
 use util::str::DOMString;
 
@@ -24,6 +26,9 @@ pub struct URL {
 
     // https://url.spec.whatwg.org/#concept-urlutils-get-the-base
     base: Option<Url>,
+
+    // https://url.spec.whatwg.org/#dom-url-searchparams
+    search_params: MutNullableHeap<JS<URLSearchParams>>,
 }
 
 impl URL {
@@ -32,6 +37,7 @@ impl URL {
             reflector_: Reflector::new(),
             url: DOMRefCell::new(url),
             base: base,
+            search_params: Default::default(),
         }
     }
 
@@ -39,6 +45,10 @@ impl URL {
         reflect_dom_object(box URL::new_inherited(url, base),
                            global, URLBinding::Wrap)
     }
+
+    pub fn set_query(&self, query: String) {
+        self.url.borrow_mut().query = Some(query);
+    }
 }
 
 impl URL {
@@ -69,8 +79,13 @@ impl URL {
                 return Err(Error::Type(format!("could not parse URL: {}", error)));
             }
         };
-        // Steps 5-8.
-        Ok(URL::new(global, parsed_url, parsed_base))
+        // Step 5: Skip (see step 8 below).
+        // Steps 6-7.
+        let result = URL::new(global, parsed_url, parsed_base);
+        // Step 8: Instead of construcing a new `URLSearchParams` object here, construct it
+        //         on-demand inside `URL::SearchParams`.
+        // Step 9.
+        Ok(result)
     }
 
     // https://url.spec.whatwg.org/#dom-url-domaintoasciidomain
@@ -189,6 +204,14 @@ impl URLMethods for URL {
     // https://url.spec.whatwg.org/#dom-url-search
     fn SetSearch(&self, value: USVString) {
         UrlHelper::SetSearch(&mut self.url.borrow_mut(), value);
+        if let Some(search_params) = self.search_params.get() {
+            search_params.set_list(self.url.borrow().query_pairs().unwrap_or_else(|| vec![]));
+        }
+    }
+
+    // https://url.spec.whatwg.org/#dom-url-searchparams
+    fn SearchParams(&self) -> Root<URLSearchParams> {
+        self.search_params.or_init(|| URLSearchParams::new(self.global().r(), Some(self)))
     }
 
     // https://url.spec.whatwg.org/#dom-url-href
diff --git a/components/script/dom/urlsearchparams.rs b/components/script/dom/urlsearchparams.rs
index 27df100aac1..bb7b1cb910c 100644
--- a/components/script/dom/urlsearchparams.rs
+++ b/components/script/dom/urlsearchparams.rs
@@ -11,6 +11,8 @@ use dom::bindings::global::GlobalRef;
 use dom::bindings::js::Root;
 use dom::bindings::reflector::{Reflector, reflect_dom_object};
 use dom::bindings::str::USVString;
+use dom::bindings::weakref::MutableWeakRef;
+use dom::url::URL;
 use encoding::types::EncodingRef;
 use url::form_urlencoded::{parse, serialize_with_encoding};
 use util::str::DOMString;
@@ -21,18 +23,21 @@ pub struct URLSearchParams {
     reflector_: Reflector,
     // https://url.spec.whatwg.org/#concept-urlsearchparams-list
     list: DOMRefCell<Vec<(String, String)>>,
+    // https://url.spec.whatwg.org/#concept-urlsearchparams-url-object
+    url: MutableWeakRef<URL>,
 }
 
 impl URLSearchParams {
-    fn new_inherited() -> URLSearchParams {
+    fn new_inherited(url: Option<&URL>) -> URLSearchParams {
         URLSearchParams {
             reflector_: Reflector::new(),
             list: DOMRefCell::new(vec![]),
+            url: MutableWeakRef::new(url),
         }
     }
 
-    pub fn new(global: GlobalRef) -> Root<URLSearchParams> {
-        reflect_dom_object(box URLSearchParams::new_inherited(), global,
+    pub fn new(global: GlobalRef, url: Option<&URL>) -> Root<URLSearchParams> {
+        reflect_dom_object(box URLSearchParams::new_inherited(url), global,
                            URLSearchParamsBinding::Wrap)
     }
 
@@ -40,7 +45,7 @@ impl URLSearchParams {
     pub fn Constructor(global: GlobalRef, init: Option<USVStringOrURLSearchParams>) ->
                        Fallible<Root<URLSearchParams>> {
         // Step 1.
-        let query = URLSearchParams::new(global);
+        let query = URLSearchParams::new(global, None);
         match init {
             Some(USVStringOrURLSearchParams::USVString(init)) => {
                 // Step 2.
@@ -55,6 +60,10 @@ impl URLSearchParams {
         // Step 4.
         Ok(query)
     }
+
+    pub fn set_list(&self, list: Vec<(String, String)>) {
+        *self.list.borrow_mut() = list;
+    }
 }
 
 impl URLSearchParamsMethods for URLSearchParams {
@@ -101,6 +110,7 @@ impl URLSearchParamsMethods for URLSearchParams {
 
     // https://url.spec.whatwg.org/#dom-urlsearchparams-set
     fn Set(&self, name: USVString, value: USVString) {
+        // Step 1.
         let mut list = self.list.borrow_mut();
         let mut index = None;
         let mut i = 0;
@@ -118,8 +128,9 @@ impl URLSearchParamsMethods for URLSearchParams {
         });
         match index {
             Some(index) => list[index].1 = value.0,
-            None => list.push((name.0, value.0)),
+            None => list.push((name.0, value.0)), // Step 2.
         };
+        // Step 3.
         self.update_steps();
     }
 
@@ -140,8 +151,10 @@ impl URLSearchParams {
 
 
 impl URLSearchParams {
-    // https://url.spec.whatwg.org/#concept-uq-update
+    // https://url.spec.whatwg.org/#concept-urlsearchparams-update
     fn update_steps(&self) {
-        // XXXManishearth Implement this when the URL interface is implemented
+        if let Some(url) = self.url.root() {
+            url.set_query(self.serialize(None));
+        }
     }
 }
diff --git a/components/script/dom/webidls/URL.webidl b/components/script/dom/webidls/URL.webidl
index 8c5d6e1580e..6843bd8b6c2 100644
--- a/components/script/dom/webidls/URL.webidl
+++ b/components/script/dom/webidls/URL.webidl
@@ -20,7 +20,7 @@ interface URL {
            attribute USVString port;
            attribute USVString pathname;
            attribute USVString search;
-  // readonly attribute URLSearchParams searchParams;
+  readonly attribute URLSearchParams searchParams;
            attribute USVString hash;
 
   // This is only doing as well as gecko right now.
diff --git a/components/script/dom/webidls/URLSearchParams.webidl b/components/script/dom/webidls/URLSearchParams.webidl
index e2075d96a6d..e0266ca6246 100644
--- a/components/script/dom/webidls/URLSearchParams.webidl
+++ b/components/script/dom/webidls/URLSearchParams.webidl
@@ -15,6 +15,8 @@ interface URLSearchParams {
   sequence<USVString> getAll(USVString name);
   boolean has(USVString name);
   void set(USVString name, USVString value);
+  // Be careful with implementing iterable interface.
+  // Search params might be mutated by URL::SetSearch while iterating (discussed in PR #10351).
   // iterable<USVString, USVString>;
   stringifier;
 };