Auto merge of #12620 - vrod:add-htmllielement-value, r=KiChjang

Implement HTMLLIElement#value

<!-- Please describe your changes on the following line: -->

- Add implementation of parse_plain_attribute from VirtualMethods trait for HTMLLIElement
- Add make_int_setter! macro
- Implement getter and setter for HTMLLIElement#value attribute
- Update test expectations for HTMLLIElement#value

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12575
- [X] There are tests for these changes

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4 files changed, 46 insertions, 1 deletions

diff --git a/components/script/dom/htmllielement.rs b/components/script/dom/htmllielement.rs
index 444fc37827c..32915a5c351 100644
--- a/components/script/dom/htmllielement.rs
+++ b/components/script/dom/htmllielement.rs
@@ -3,12 +3,16 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use dom::bindings::codegen::Bindings::HTMLLIElementBinding;
+use dom::bindings::codegen::Bindings::HTMLLIElementBinding::HTMLLIElementMethods;
+use dom::bindings::inheritance::Castable;
 use dom::bindings::js::Root;
 use dom::bindings::str::DOMString;
 use dom::document::Document;
 use dom::htmlelement::HTMLElement;
 use dom::node::Node;
+use dom::virtualmethods::VirtualMethods;
 use string_cache::Atom;
+use style::attr::AttrValue;
 
 #[dom_struct]
 pub struct HTMLLIElement {
@@ -31,3 +35,24 @@ impl HTMLLIElement {
                            HTMLLIElementBinding::Wrap)
     }
 }
+
+impl HTMLLIElementMethods for HTMLLIElement {
+    // https://html.spec.whatwg.org/multipage/#dom-li-value
+    make_int_getter!(Value, "value");
+
+    // https://html.spec.whatwg.org/multipage/#dom-li-value
+    make_int_setter!(SetValue, "value");
+}
+
+impl VirtualMethods for HTMLLIElement {
+    fn super_type(&self) -> Option<&VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &VirtualMethods)
+    }
+
+    fn parse_plain_attribute(&self, name: &Atom, value: DOMString) -> AttrValue {
+        match name {
+            &atom!("value") => AttrValue::from_i32(value.into(), 0),
+            _ => self.super_type().unwrap().parse_plain_attribute(name, value),
+        }
+    }
+}
diff --git a/components/script/dom/macros.rs b/components/script/dom/macros.rs
index 58af2b28ac6..2b29ec8014c 100644
--- a/components/script/dom/macros.rs
+++ b/components/script/dom/macros.rs
@@ -47,6 +47,22 @@ macro_rules! make_limited_int_setter(
 );
 
 #[macro_export]
+macro_rules! make_int_setter(
+    ($attr:ident, $htmlname:tt, $default:expr) => (
+        fn $attr(&self, value: i32) {
+            use dom::bindings::inheritance::Castable;
+            use dom::element::Element;
+
+            let element = self.upcast::<Element>();
+            element.set_int_attribute(&atom!($htmlname), value)
+        }
+    );
+    ($attr:ident, $htmlname:tt) => {
+        make_int_setter!($attr, $htmlname, 0);
+    };
+);
+
+#[macro_export]
 macro_rules! make_int_getter(
     ($attr:ident, $htmlname:tt, $default:expr) => (
         fn $attr(&self) -> i32 {
diff --git a/components/script/dom/virtualmethods.rs b/components/script/dom/virtualmethods.rs
index b42e8b676c3..d4cf1609568 100644
--- a/components/script/dom/virtualmethods.rs
+++ b/components/script/dom/virtualmethods.rs
@@ -29,6 +29,7 @@ use dom::htmliframeelement::HTMLIFrameElement;
 use dom::htmlimageelement::HTMLImageElement;
 use dom::htmlinputelement::HTMLInputElement;
 use dom::htmllabelelement::HTMLLabelElement;
+use dom::htmllielement::HTMLLIElement;
 use dom::htmllinkelement::HTMLLinkElement;
 use dom::htmlmediaelement::HTMLMediaElement;
 use dom::htmlmetaelement::HTMLMetaElement;
@@ -179,6 +180,9 @@ pub fn vtable_for(node: &Node) -> &VirtualMethods {
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLLabelElement)) => {
             node.downcast::<HTMLLabelElement>().unwrap() as &VirtualMethods
         }
+        NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLLIElement)) => {
+            node.downcast::<HTMLLIElement>().unwrap() as &VirtualMethods
+        }
         NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLLinkElement)) => {
             node.downcast::<HTMLLinkElement>().unwrap() as &VirtualMethods
         }
diff --git a/components/script/dom/webidls/HTMLLIElement.webidl b/components/script/dom/webidls/HTMLLIElement.webidl
index a2fcd9cc7d3..ea7d574eba4 100644
--- a/components/script/dom/webidls/HTMLLIElement.webidl
+++ b/components/script/dom/webidls/HTMLLIElement.webidl
@@ -4,7 +4,7 @@
 
 // https://html.spec.whatwg.org/multipage/#htmllielement
 interface HTMLLIElement : HTMLElement {
-  //         attribute long value;
+  attribute long value;
 
   // also has obsolete members
 };