Preserve templates containing ignored nested OOB swaps

src/htmx.js

@@ -1899,8 +1899,10 @@ var htmx = (function() {
    */
   function findAndSwapOobElements(fragment, settleInfo, rootNode) {
     var oobElts = findAll(fragment, '[hx-swap-oob], [data-hx-swap-oob]')
+    var hasOobSwaps = false
     forEach(oobElts, function(oobElement) {
       if (htmx.config.allowNestedOobSwaps || oobElement.parentElement === null) {
+        hasOobSwaps = true
         const oobValue = getAttributeValue(oobElement, 'hx-swap-oob')
         if (oobValue != null) {
           oobSwap(oobValue, oobElement, settleInfo, rootNode)
@@ -1910,7 +1912,7 @@ var htmx = (function() {
         oobElement.removeAttribute('data-hx-swap-oob')
       }
     })
-    return oobElts.length > 0
+    return hasOobSwaps
   }
 
   /**

test/attributes/hx-swap-oob.js

@@ -222,6 +222,22 @@ describe('hx-swap-oob attribute', function() {
     should.equal(byId('d1').innerHTML, 'Foo')
   })
 
+  for (const attribute of ['hx-swap-oob', 'data-hx-swap-oob']) {
+    it('keeps templates containing ignored nested oob swaps with ' + attribute, function() {
+      htmx.config.allowNestedOobSwaps = false
+      this.server.respondWith('GET', '/test', '<template id="kept"><div><span ' + attribute + '="innerHTML:#d1">Nested</span></div></template>')
+      var button = make('<button hx-get="/test">Click</button>')
+      var target = make('<div id="d1">Original</div>')
+      button.click()
+      this.server.respond()
+      target.innerHTML.should.equal('Original')
+      var template = button.querySelector('template')
+      should.not.equal(template, null)
+      template.content.querySelector('span').textContent.should.equal('Nested')
+      template.content.querySelector('span').hasAttribute(attribute).should.equal(false)
+    })
+  }
+
   it('oob swap keeps templates not used for oob swap encapsulation', function() {
     this.server.respondWith('GET', '/test', '' +
         'Clicked<template></template>')

www/content/attributes/hx-swap-oob.md

@@ -118,6 +118,7 @@ By default, any element with `hx-swap-oob=` attribute anywhere in the response i
 This can be problematic when using [template fragments](https://htmx.org/essays/template-fragments/) where a fragment may be reused as an oob-swap target and also as part of a bigger fragment. When the bigger fragment is the main response the inner fragment will still be processed as an oob swap, removing it from the dom.
 
 This behavior can be changed by setting the config `htmx.config.allowNestedOobSwaps` to `false`. If this config option is `false`, OOB swaps are only processed when the element is *adjacent to* the main response element, OOB swaps elsewhere will be ignored and oob-swap-related attributes stripped.
+Templates containing only ignored nested OOB elements are retained in the main response; they are not discarded as OOB encapsulation wrappers.
 
 ## Notes