Auto merge of #19038 - CJ8664:master, r=jdm

Added implementation for itemprop and itemtype along with test files

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- [x] `./mach test-tidy` does not report any errors

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- [x] There are tests for these changes OR

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components/script/dom/htmlelement.rs

@@ -31,6 +31,7 @@ use dom::virtualmethods::VirtualMethods;
 use dom_struct::dom_struct;
 use html5ever::{LocalName, Prefix};
 use std::ascii::AsciiExt;
+use std::collections::HashSet;
 use std::default::Default;
 use std::rc::Rc;
 use style::attr::AttrValue;
@@ -277,6 +278,38 @@ impl HTMLElementMethods for HTMLElement {
         }
     }
 
+    // https://html.spec.whatwg.org/multipage/#attr-itemtype
+    fn Itemtypes(&self) -> Option<Vec<DOMString>> {
+        let atoms = self.element.get_tokenlist_attribute(&local_name!("itemtype"), );
+
+        if atoms.is_empty() {
+            return None;
+        }
+
+        let mut item_attr_values = HashSet::new();
+        for attr_value in &atoms {
+            item_attr_values.insert(DOMString::from(String::from(attr_value.trim())));
+        }
+
+        Some(item_attr_values.into_iter().collect())
+    }
+
+    // https://html.spec.whatwg.org/multipage/#names:-the-itemprop-attribute
+    fn PropertyNames(&self) -> Option<Vec<DOMString>> {
+        let atoms = self.element.get_tokenlist_attribute(&local_name!("itemprop"), );
+
+        if atoms.is_empty() {
+            return None;
+        }
+
+        let mut item_attr_values = HashSet::new();
+        for attr_value in &atoms {
+            item_attr_values.insert(DOMString::from(String::from(attr_value.trim())));
+        }
+
+        Some(item_attr_values.into_iter().collect())
+    }
+
     // https://html.spec.whatwg.org/multipage/#dom-click
     fn Click(&self) {
         if !self.upcast::<Element>().disabled_state() {
@@ -577,4 +610,17 @@ impl VirtualMethods for HTMLElement {
         }
         self.update_sequentially_focusable_status();
     }
+
+    fn parse_plain_attribute(&self, name: &LocalName, value: DOMString) -> AttrValue {
+        match name {
+            &local_name!("itemprop") => AttrValue::from_serialized_tokenlist(value.into()),
+            &local_name!("itemtype") => AttrValue::from_serialized_tokenlist(value.into()),
+            _ => {
+                self.super_type().unwrap().parse_plain_attribute(
+                    name,
+                    value,
+                )
+            },
+        }
+    }
 }

components/script/dom/webidls/HTMLElement.webidl

@@ -18,9 +18,14 @@ interface HTMLElement : Element {
 
   // microdata
   //         attribute boolean itemScope;
+
   //         attribute DOMString itemId;
   //readonly attribute HTMLPropertiesCollection properties;
   //         attribute any itemValue; // acts as DOMString on setting
+  [Pref="dom.microdata.testing.enabled"]
+  sequence<DOMString>? propertyNames();
+  [Pref="dom.microdata.testing.enabled"]
+  sequence<DOMString>? itemtypes();
 
   // user interaction
   [CEReactions]