Implement disabled attribute for <link rel="stylesheet"> (#36446)

Adds support for both the content and the IDL attribute.
Note this doesn't cover dynamic updates to `document.styleSheets` and
the owner node of the sheet.

Testing: Covered by WPT
Fixes: #26739

Signed-off-by: Oriol Brufau <obrufau@igalia.com>

components/script/dom/htmllinkelement.rs

@@ -114,6 +114,8 @@ pub(crate) struct HTMLLinkElement {
     any_failed_load: Cell<bool>,
     /// A monotonically increasing counter that keeps track of which stylesheet to apply.
     request_generation_id: Cell<RequestGenerationId>,
+    /// <https://html.spec.whatwg.org/multipage/#explicitly-enabled>
+    is_explicitly_enabled: Cell<bool>,
 }
 
 impl HTMLLinkElement {
@@ -133,6 +135,7 @@ impl HTMLLinkElement {
             pending_loads: Cell::new(0),
             any_failed_load: Cell::new(false),
             request_generation_id: Cell::new(RequestGenerationId(0)),
+            is_explicitly_enabled: Cell::new(false),
         }
     }
 
@@ -196,6 +199,12 @@ impl HTMLLinkElement {
         self.relations.get().contains(LinkRelations::ALTERNATE)
     }
 
+    pub(crate) fn is_effectively_disabled(&self) -> bool {
+        (self.is_alternate() && !self.is_explicitly_enabled.get()) ||
+            self.upcast::<Element>()
+                .has_attribute(&local_name!("disabled"))
+    }
+
     fn clean_stylesheet_ownership(&self) {
         if let Some(cssom_stylesheet) = self.cssom_stylesheet.get() {
             cssom_stylesheet.set_owner(None);
@@ -221,11 +230,18 @@ impl VirtualMethods for HTMLLinkElement {
         self.super_type()
             .unwrap()
             .attribute_mutated(attr, mutation, can_gc);
-        if !self.upcast::<Node>().is_connected() || mutation.is_removal() {
+
+        let local_name = attr.local_name();
+        let is_removal = mutation.is_removal();
+        if *local_name == local_name!("disabled") {
+            self.handle_disabled_attribute_change(!is_removal);
             return;
         }
 
-        match *attr.local_name() {
+        if !self.upcast::<Node>().is_connected() || is_removal {
+            return;
+        }
+        match *local_name {
             local_name!("rel") | local_name!("rev") => {
                 self.relations
                     .set(LinkRelations::for_element(self.upcast()));
@@ -472,6 +488,18 @@ impl HTMLLinkElement {
         );
     }
 
+    /// <https://html.spec.whatwg.org/multipage/#attr-link-disabled>
+    fn handle_disabled_attribute_change(&self, disabled: bool) {
+        if !disabled {
+            self.is_explicitly_enabled.set(true);
+        }
+        if let Some(stylesheet) = self.get_stylesheet() {
+            if stylesheet.set_disabled(disabled) {
+                self.stylesheet_list_owner().invalidate_stylesheets();
+            }
+        }
+    }
+
     fn handle_favicon_url(&self, href: &str, _sizes: &Option<String>) {
         let document = self.owner_document();
         match document.base_url().join(href) {
@@ -567,6 +595,12 @@ impl HTMLLinkElementMethods<crate::DomTypeHolder> for HTMLLinkElement {
     // https://html.spec.whatwg.org/multipage/#dom-link-type
     make_setter!(SetType, "type");
 
+    // https://html.spec.whatwg.org/multipage/#dom-link-disabled
+    make_bool_getter!(Disabled, "disabled");
+
+    // https://html.spec.whatwg.org/multipage/#dom-link-disabled
+    make_bool_setter!(SetDisabled, "disabled");
+
     // https://html.spec.whatwg.org/multipage/#dom-link-rellist
     fn RelList(&self) -> DomRoot<DOMTokenList> {
         self.rel_list.or_init(|| {

components/script/stylesheet_loader.rs

@@ -214,7 +214,7 @@ impl FetchResponseListener for StylesheetContext {
                             document.quirks_mode(),
                         ));
 
-                        if link.is_alternate() {
+                        if link.is_effectively_disabled() {
                             sheet.set_disabled(true);
                         }
 

components/script_bindings/webidls/HTMLLinkElement.webidl

@@ -13,17 +13,24 @@ interface HTMLLinkElement : HTMLElement {
            attribute DOMString? crossOrigin;
   [CEReactions]
            attribute DOMString rel;
+  // [CEReactions] attribute DOMString as;
   [SameObject, PutForwards=value] readonly attribute DOMTokenList relList;
   [CEReactions]
            attribute DOMString media;
+  [CEReactions]
+           attribute DOMString integrity;
   [CEReactions]
            attribute DOMString hreflang;
   [CEReactions]
            attribute DOMString type;
-  [CEReactions]
+  // [SameObject, PutForwards=value] readonly attribute DOMTokenList sizes;
-           attribute DOMString integrity;
+  // [CEReactions] attribute USVString imageSrcset;
+  // [CEReactions] attribute DOMString imageSizes;
   [CEReactions]
            attribute DOMString referrerPolicy;
+  // [SameObject, PutForwards=value] readonly attribute DOMTokenList blocking;
+  [CEReactions] attribute boolean disabled;
+  // [CEReactions] attribute DOMString fetchPriority;
 
   // also has obsolete members
 };

tests/wpt/meta/css/cssom/HTMLLinkElement-disabled-003.html.ini

@@ -1,4 +0,0 @@
-[HTMLLinkElement-disabled-003.html]
-  [HTMLLinkElement.disabled's explicitly enabled state persists when disconnected and connected again]
-    expected: FAIL
-

tests/wpt/meta/css/cssom/HTMLLinkElement-disabled-004.html.ini

@@ -1,4 +0,0 @@
-[HTMLLinkElement-disabled-004.html]
-  [HTMLLinkElement.disabled's explicitly enabled state doesn't persist on clones]
-    expected: FAIL
-

tests/wpt/meta/css/cssom/HTMLLinkElement-disabled-007.html.ini

@@ -1,4 +0,0 @@
-[HTMLLinkElement-disabled-007.html]
-  [HTMLLinkElement.disabled setter sets the explicitly enabled state if toggled back and forth.]
-    expected: FAIL
-

tests/wpt/meta/css/cssom/HTMLLinkElement-disabled-alternate.html.ini

@@ -1,2 +0,0 @@
-[HTMLLinkElement-disabled-alternate.html]
-  expected: FAIL

tests/wpt/meta/html/dom/idlharness.https.html.ini

@@ -6052,9 +6052,6 @@
   [HTMLLinkElement interface: attribute blocking]
     expected: FAIL
 
-  [HTMLLinkElement interface: attribute disabled]
-    expected: FAIL
-
   [HTMLLinkElement interface: attribute fetchPriority]
     expected: FAIL
 
@@ -6073,9 +6070,6 @@
   [HTMLLinkElement interface: document.createElement("link") must inherit property "blocking" with the proper type]
     expected: FAIL
 
-  [HTMLLinkElement interface: document.createElement("link") must inherit property "disabled" with the proper type]
-    expected: FAIL
-
   [HTMLLinkElement interface: document.createElement("link") must inherit property "fetchPriority" with the proper type]
     expected: FAIL
 

tests/wpt/meta/subresource-integrity/subresource-integrity.html.ini

@@ -1,7 +1,4 @@
 [subresource-integrity.html]
-  [Style: Same-origin with correct sha256 and sha512 hash, rel='alternate stylesheet' enabled]
-    expected: FAIL
-
   [Script: Same-origin with non-Base64 hash.]
     expected: FAIL