Fix bug when straddling void nodes

Author: wooorm

lib/handlers/li.js

@@ -6,7 +6,6 @@
  */
 
 import {convertElement} from 'hast-util-is-element'
-import {shallow} from '../util/shallow.js'
 import {wrapChildren} from '../util/wrap-children.js'
 
 const p = convertElement('p')
@@ -36,14 +35,13 @@ export function li(h, node) {
         checkbox.properties.type === 'radio')
     ) {
       checked = Boolean(checkbox.properties.checked)
-      clone = Object.assign(shallow(node), {
+      clone = {
+        ...node,
         children: [
-          Object.assign(shallow(head), {
-            children: head.children.slice(1)
-          }),
+          {...head, children: head.children.slice(1)},
           ...node.children.slice(1)
         ]
-      })
+      }
     }
   }
 

lib/util/shallow.js

@@ -6,7 +6,6 @@
 
 import extend from 'extend'
 import {phrasing} from 'mdast-util-phrasing'
-import {shallow} from './shallow.js'
 
 /**
  * @param {Array.<MdastNode>} nodes
@@ -148,18 +147,22 @@ function split(node) {
   /**
    * Use `child`, add `parent` as its first child, put the original children
    * into `parent`.
+   * If `child` is not a parent, `parent` will not be added.
    *
    * @param {MdastNode} child
    * @returns {MdastNode}
    */
   function onnonphrasing(child) {
-    return Object.assign(shallow(child), {
-      children: [
-        Object.assign(extend(true, {}, shallow(node)), {
-          children: 'children' in child ? child.children : []
-        })
-      ]
-    })
+    if ('children' in child && 'children' in node) {
+      const {children, ...rest} = node
+      return {
+        ...child,
+        // @ts-expect-error: assume matching parent & child.
+        children: [{...extend(true, {}, rest), children: child.children}]
+      }
+    }
+
+    return {...child}
   }
 
   /**
@@ -169,7 +172,10 @@ function split(node) {
    * @returns {MdastNode}
    */
   function onphrasing(nodes) {
-    return Object.assign(extend(true, {}, shallow(node)), {children: nodes})
+    // @ts-expect-error: assume parent.
+    const {children, ...rest} = node
+    // @ts-expect-error: assume matching parent & child.
+    return {...extend(true, {}, rest), children: nodes}
   }
 }
 

lib/util/wrap.js

@@ -65,3 +65,7 @@ <h2>Overlap explicit</h2>
   </object>
   <p>I’m quite proud of it.</p>
 </section>
+
+<section>
+  <a href="#url">a<hr>b</a>
+</section>

test/fixtures/straddling/index.html

@@ -55,3 +55,9 @@ To see the cat simulator, use one of the following links:
 Alternatively, upgrade to the Mellblom Browser.
 
 I’m quite proud of it.
+
+[a](#url)
+
+***
+
+[b](#url)