fix #2932: check parent is null for swap

src/htmx.js

@@ -1661,9 +1661,13 @@ var htmx = (function() {
     /** @type {Node} */
     let newElt
     const eltBeforeNewContent = target.previousSibling
-    insertNodesBefore(parentElt(target), target, fragment, settleInfo)
+    const parentNode = parentElt(target)
+    if (!parentNode) { // when parent node disappears, we can't do anything
+      return
+    }
+    insertNodesBefore(parentNode, target, fragment, settleInfo)
     if (eltBeforeNewContent == null) {
-      newElt = parentElt(target).firstChild
+      newElt = parentNode.firstChild
     } else {
       newElt = eltBeforeNewContent.nextSibling
     }
@@ -1725,7 +1729,10 @@ var htmx = (function() {
    */
   function swapDelete(target) {
     cleanUpElement(target)
-    return parentElt(target).removeChild(target)
+    const parent = parentElt(target)
+    if (parent) {
+      return parent.removeChild(target)
+    }
   }
 
   /**

test/core/api.js

@@ -403,4 +403,26 @@ describe('Core htmx API test', function() {
     output.innerHTML.should.be.equal('<div>Swapped!</div>')
     oobDiv.innerHTML.should.be.equal('OOB Swapped!')
   })
+
+  it('swap delete works when parent is removed', function() {
+    this.server.respondWith('DELETE', '/test', 'delete')
+
+    var parent = make('<div><div id="d1" hx-swap="delete" hx-delete="/test">click me</div></div>')
+    var div = htmx.find(parent, '#d1')
+    div.click()
+    parent.remove()
+    this.server.respond()
+    parent.children.length.should.equal(0)
+  })
+
+  it('swap outerHTML works when parent is removed', function() {
+    this.server.respondWith('GET', '/test', 'delete')
+
+    var parent = make('<div><div id="d1" hx-swap="outerHTML" hx-get="/test">click me</div></div>')
+    var div = htmx.find(parent, '#d1')
+    div.click()
+    parent.remove()
+    this.server.respond()
+    parent.children.length.should.equal(0)
+  })
 })