Improve merging of math lists (mathjax/MathJax#3301).

dpvc · dpvc · commit d50a25e59141 · 2024-10-24T09:12:17.000-04:00
diff --git a/ts/handlers/html/HTMLDocument.ts b/ts/handlers/html/HTMLDocument.ts
@@ -124,14 +124,16 @@ export class HTMLDocument<N, T, D> extends AbstractMathDocument<N, T, D> {
     nodes: HTMLNodeArray<N, T>
   ): Location<N, T> {
     const adaptor = this.adaptor;
-    for (const list of nodes[N]) {
-      const [node, n] = list;
+    const inc = 1 / (nodes[N].length || 1);
+    let i = N;
+    for (const [node, n] of nodes[N]) {
       if (index <= n && adaptor.kind(node) === '#text') {
-        return { node: node, n: Math.max(index, 0), delim: delim };
+        return { i, node, n: Math.max(index, 0), delim };
       }
       index -= n;
+      i += inc;
     }
-    return { node: null, n: 0, delim: delim };
+    return { node: null, n: 0, delim };
   }
 
   /**
@@ -298,9 +300,9 @@ export class HTMLDocument<N, T, D> extends AbstractMathDocument<N, T, D> {
   /**
    * @param {N} head     The document <head>
    * @param {string} id  The id of the stylesheet to find
-   * @param {N|null}     The stylesheet with the given ID
+   * @returns {N|null}   The stylesheet with the given ID
    */
-  protected findSheet(head: N, id: string) {
+  protected findSheet(head: N, id: string): N | null {
     if (id) {
       for (const sheet of this.adaptor.tags(head, 'style')) {
         if (this.adaptor.getAttribute(sheet, 'id') === id) {
