Auto merge of #10512 - KiChjang:base-element-attr, r=Ms2ger

Implement HTMLBaseElement attributes

The remaining test failure in `base_multiple.html` looks like there's a problem with the test itself (it does not have a `<base>` tag at all).

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2 files changed, 31 insertions, 3 deletions

diff --git a/components/script/dom/htmlbaseelement.rs b/components/script/dom/htmlbaseelement.rs
index 7f1ce7641d3..241c209c7a8 100644
--- a/components/script/dom/htmlbaseelement.rs
+++ b/components/script/dom/htmlbaseelement.rs
@@ -2,8 +2,9 @@
  * 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::attr::Attr;
+use dom::attr::{Attr, AttrValue};
 use dom::bindings::codegen::Bindings::HTMLBaseElementBinding;
+use dom::bindings::codegen::Bindings::HTMLBaseElementBinding::HTMLBaseElementMethods;
 use dom::bindings::inheritance::Castable;
 use dom::bindings::js::Root;
 use dom::document::Document;
@@ -60,6 +61,33 @@ impl HTMLBaseElement {
     }
 }
 
+impl HTMLBaseElementMethods for HTMLBaseElement {
+    // https://html.spec.whatwg.org/multipage/#dom-base-href
+    fn Href(&self) -> DOMString {
+        let document = document_from_node(self);
+
+        // Step 1.
+        if !self.upcast::<Element>().has_attribute(&atom!("href")) {
+            return DOMString::from(document.base_url().serialize());
+        }
+
+        // Step 2.
+        let fallback_base_url = document.fallback_base_url();
+
+        // Step 3.
+        let url = self.upcast::<Element>().get_url_attribute(&atom!("href"));
+
+        // Step 4.
+        let url_record = fallback_base_url.join(&*url);
+
+        // Step 5, 6.
+        DOMString::from(url_record.ok().map_or("".to_owned(), |record| record.serialize()))
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-base-href
+    make_url_setter!(SetHref, "href");
+}
+
 impl VirtualMethods for HTMLBaseElement {
     fn super_type(&self) -> Option<&VirtualMethods> {
         Some(self.upcast::<HTMLElement>() as &VirtualMethods)
diff --git a/components/script/dom/webidls/HTMLBaseElement.webidl b/components/script/dom/webidls/HTMLBaseElement.webidl
index 5c59c62f9be..549a6df1004 100644
--- a/components/script/dom/webidls/HTMLBaseElement.webidl
+++ b/components/script/dom/webidls/HTMLBaseElement.webidl
@@ -5,6 +5,6 @@
 
 // https://html.spec.whatwg.org/multipage/#htmlbaseelement
 interface HTMLBaseElement : HTMLElement {
-  //         attribute DOMString href;
-  //         attribute DOMString target;
+           attribute DOMString href;
+//           attribute DOMString target;
 };