Flesh out the idea more

Author: foolip

source

@@ -124370,11 +124370,12 @@ partial interface <span>ShadowRoot</span> {
 };
 
 dictionary <dfn dictionary>PatchUnsafeOptions</dfn> {
-  TrustedTransformStream <dfn dict-member for="PatchUnsafeOptions" data-x="dom-PatchUnsafeOptions-trustedTransformStream">trustedTransformStream</dfn>;
+  boolean <dfn dict-member for="PatchUnsafeOptions" data-x="dom-PatchUnsafeOptions-runScripts">runScripts</dfn> = false;
 };</code></pre>
 
   <div w-nodev>
 
+  <div algorithm>
   <p><code>Element</code>'s <dfn method for="Element"><code
   data-x="dom-Element-patchUnsafe">patchUnsafe(<var>options</var>)</code></dfn> method steps
   are:</p>
@@ -124383,25 +124384,58 @@ dictionary <dfn dictionary>PatchUnsafeOptions</dfn> {
    <li><p>Let <var>writable</var> be a new WritableStream.</p></li>
 
    <li>
-    <p>If <var>options</var>["<code data-x="dom-PatchUnsafeOptions-trustedTransformStream">trustedTransformStream</code>"] <span data-x="map exists">exists</span>:</p>
+    <p>👋 Sketch of the streams setup:</p>
 
     <ol>
-     <li><p>Set <var>writable</var> to the result of piping <var>writable</var> through <var>options</var>["trustedTransformStream"].</p></li>
+     <li><p>Incoming chunks must all be of the same type, either strings, bytes, or a trusted types
+     wrapper.</p></li>
+
+     <li>
+      <p>Some decisions are made based on the first chunk:</p>
+
+      <ol>
+       <li><p>If it's not a trusted types wrapper and there is a default TT policy, create a
+       transform stream using <code data-x="">createTransformStream</code> from the default policy.
+       Then pipe chunks through that transform stream.</p></li>
+
+       <li><p>If it's bytes, create an UTF-8 TextDecoderStream and pipe chunks through that.</p></li>
+
+       <li><p>TODO: which should happen first? should we allow the TT transform stream to take bytes
+       as input, or guarantee that it's strings by then?</p></li>
+      </ol>
+     </li>
+
+     <li><p>As chunks are coming through, before handing them to the parser, check that they're all
+     of the same type. For trusted types, also check that the chunks are in the same order and not
+     duplicated/filtered/reordered.</p></li>
     </ol>
    </li>
 
    <li>
-    <p>Otherwise:</p>
+    <p>👋 Sketch of the parser setup:</p>
 
     <ol>
-     <li><p>If there's a default TT policy, use that and wrap <var>writable</var> 👋</p></li>
+     <li><p>Let <var>parser</var> be a new fragment parser.</p></li>
+
+     <li><p>Add <span>this</span> to the <span>stack of open elements</span>.</p></li>
+
+     <li><p>If <var>options</var>["<code data-x="dom-PatchUnsafeOptions-runScripts">runScripts</code>"],
+     don't mark scripts as already executed.</p></li>
+
+     <li><p>Write chunks into the parser as they are written to <var>writable</var>.</p></li>
+
+     <li><p>When a <code>template</code> element with a  <code data-x="">patchfor</code> attribute
+     comes out of the parser, find the target node by ID and set that as the parser's insertion
+     point.</p></li>
+
+     <li><p>The first time an element is patched, replace all children. Subsequent patches to the
+     same target append children.</p></li>
     </ol>
    </li>
 
-   <li><p>Create a new parser and do all the actual work 👋</p></li>
-
    <li><p>Return <var>writable</var>.</p></li>
   </ol>
+  </div>
 
   <div class="example">
    <p>Do a thing like this:</p>
@@ -124416,19 +124450,21 @@ dictionary <dfn dictionary>PatchUnsafeOptions</dfn> {
   }
 });
 
-const trustedTransformStream = policy.createTransformStream(input);
-const writable = element.patchUnsafe({ trustedTransformStream });
 const response = await fetch('/fragments/something');
-response.body.pipeTo(writable);</code></pre>
+const transform = policy.createTransformStream();
+const writable = element.patchUnsafe();
+await response.body.pipeThrough(transform).pipeTo(writable);</code></pre>
   </div>
 
+  <div algorithm>
   <p><code>ShadowRoot</code>'s <dfn method for="ShadowRoot"><code
   data-x="dom-ShadowRoot-patchUnsafe">patchUnsafe(<var>options</var>)</code></dfn> method steps
   are:</p>
 
   <ol>
    <li>TODO</li>
   </ol>
+  </div>
 
   </div>