Fix script-blocking style sheet infrastructure

In particular, fixes whatwg#4325, which documents a case where <link rel="stylesheet"> would increment, and never decrement, the script-blocking style sheet counter. To do this without increasing the amount of action-at-a-distance in the spec, we move from a script-blocking style sheet counter to a script-blocking style sheet set. That also matches implementations better, and sets us up for fixing other issues in this area.
josepharhar · Jan 27, 2023 · 901c8c5 · 901c8c5
1 parent a9f103c
commit 901c8c5
Showing 1 changed file with 34 additions and 23 deletions.
diff --git a/source b/source
@@ -16879,9 +16879,9 @@ console.log(style.disabled); // false</code></pre>
     base URL don't affect the CSS -->
    </li>
 
-   <li><p>If <var>element</var> <span>contributes a script-blocking style sheet</span>, increment
-   <var>element</var>'s <span>node document</span>'s <span>script-blocking style sheet
-   counter</span> by 1.</p></li>
+   <li><p>If <var>element</var> <span>contributes a script-blocking style sheet</span>, <span
+   data-x="set append">append</span> <var>element</var> to its <span>node document</span>'s
+   <span>script-blocking style sheet set</span>.</p></li>
 
    <li><p>If <var>element</var>'s <code data-x="attr-style-media">media</code> attribute's value
    <span>matches the environment</span> and <var>element</var> is
@@ -16933,10 +16933,11 @@ console.log(style.disabled); // false</code></pre>
 
       <ol>
        <li><p><span>Assert</span>: <var>element</var>'s <span>node document</span>'s
-       <span>script-blocking style sheet counter</span> is greater than 0.</p></li>
+       <span>script-blocking style sheet set</span> <span data-x="list contains">contains</span>
+       <var>element</var>.</p></li>
 
-       <li><p>Decrement <var>element</var>'s <span>node document</span>'s <span>script-blocking
-       style sheet counter</span> by 1.</p></li>
+       <li><p><span data-x="list remove">Remove</span> <var>element</var> from its <span>node
+       document</span>'s <span>script-blocking style sheet set</span>.</p></li>
       </ol>
      </li>
 
@@ -17038,23 +17039,24 @@ console.log(style.disabled); // false</code></pre>
   <code>&lt;?xml-stylesheet?></code> PIs. However, this has not yet been thoroughly
   investigated.</p>
 
-  <p>A <code>Document</code> has a <dfn>script-blocking style sheet counter</dfn>, which is a
-  number, initially 0.</p>
+  <p>A <code>Document</code> has a <dfn>script-blocking style sheet set</dfn>, which is an <span
+  data-x="set">ordered set</span>, initially empty.</p>
 
   <p>A <code>Document</code> <var>document</var> <dfn>has a style sheet that is blocking
   scripts</dfn> if the following steps return true:</p>
 
   <ol>
-   <li><p>If <var>document</var>'s <span>script-blocking style sheet counter</span> is greater than
-   0, then return true.</p></li>
+   <li><p>If <var>document</var>'s <span>script-blocking style sheet set</span> is not <span
+   data-x="list empty">empty</span>, then return true.</p></li>
 
    <li><p>If <var>document</var>'s <span>node navigable</span> is null, then return false.</p></li>
 
    <li><p>Let <var>containerDocument</var> be <var>document</var>'s <span>node navigable</span>'s
    <span data-x="nav-container">container document</span>.</p></li>
 
    <li><p>If <var>containerDocument</var> is non-null and <var>containerDocument</var>'s
-   <span>script-blocking style sheet counter</span> is greater than 0, then return true.</p></li>
+   <span>script-blocking style sheet set</span> is not <span data-x="list empty">empty</span>, then
+   return true.</p></li>
 
    <li><p>Return false.</p></li>
   </ol>
@@ -26592,9 +26594,9 @@ document.body.appendChild(wbr);</code></pre>
    <li><p>If <var>el</var>'s <code data-x="attr-link-disabled">disabled</code> attribute is set,
    then return false.</p></li>
 
-   <li><p>If <var>el</var> <span>contributes a script-blocking style sheet</span>, increment
-   <var>el</var>'s <span>node document</span>'s <span>script-blocking style sheet counter</span> by
-   1.</p></li>
+   <li><p>If <var>el</var> <span>contributes a script-blocking style sheet</span>, <span data-x="set
+   append">append</span> <var>el</var> to its <span>node document</span>'s <span>script-blocking
+   style sheet set</span>.</p></li>
 
    <li><p>If <var>el</var>'s <code data-x="attr-link-media">media</code> attribute's value
    <span>matches the environment</span> and <var>el</var> is
@@ -26629,10 +26631,19 @@ document.body.appendChild(wbr);</code></pre>
    <li><p>If the resource's <span data-x="Content-Type">Content-Type metadata</span> is not
    <code>text/css</code>, then set <var>success</var> to false.</p></li>
 
-   <li><p>If <var>el</var> no longer creates an <span>external resource link</span> that contributes
-   to the styling processing model, or if, since the resource in question was <span
-   data-x="fetch and process the linked resource">fetched</span>, it has become appropriate to <span
-   data-x="fetch and process the linked resource">fetch</span> it again, then return.</p></li>
+   <li>
+    <p>If <var>el</var> no longer creates an <span>external resource link</span> that contributes to
+    the styling processing model, or if, since the resource in question was <span data-x="fetch and
+    process the linked resource">fetched</span>, it has become appropriate to <span data-x="fetch
+    and process the linked resource">fetch</span> it again, then:</p>
+
+    <ol>
+     <li><p><span data-x="list remove">Remove</span> <var>el</var> from <var>el</var>'s <span>node
+     document</span>'s <span>script-blocking style sheet set</span>.</p></li>
+
+     <li><p>Return.</p></li>
+    </ol>
+   </li>
 
    <li><p>If <var>el</var> has an <span>associated CSS style sheet</span>, <span data-x="remove a
    CSS style sheet">remove the CSS style sheet</span>.</p></li>
@@ -26727,10 +26738,10 @@ document.body.appendChild(wbr);</code></pre>
 
     <ol>
      <li><p><span>Assert</span>: <var>el</var>'s <span>node document</span>'s <span>script-blocking
-     style sheet counter</span> is greater than 0.</p></li>
+     style sheet set</span> <span data-x="list contains">contains</span> <var>el</var>.</p></li>
 
-     <li><p>Decrement <var>el</var>'s <span>node document</span>'s <span>script-blocking style
-     sheet counter</span> by 1.</p></li>
+     <li><p><span data-x="list remove">Remove</span> <var>el</var> from its <span>node
+     document</span>'s <span>script-blocking style sheet set</span>.</p></li>
     </ol>
    </li>
 
@@ -77791,8 +77802,8 @@ partial interface <span id="NavigatorUserActivation-partial">Navigator</span> {
      and <span>continue</span>.</p></li>
 
      <li>
-      <p>If <var>doc</var>'s <span>script-blocking style sheet counter</span> is greater than 0,
-      then return.</p>
+      <p>If <var>doc</var>'s <span>script-blocking style sheet set</span> is not <span data-x="list
+      empty">empty</span>, then return.</p>
 
       <p class="note">In this case, <var>element</var> is the currently-best candidate, but
       <var>doc</var> is not ready for autofocusing. We'll try again next time <span>flush