[BUGFIX] {{#in-element}} with DocumentFragment targets, continued

packages/@ember/-internals/glimmer/lib/renderer.ts

@@ -353,15 +353,15 @@ export class Renderer extends BaseRenderer {
   }
 
   getBounds(component: View): {
-    parentElement: SimpleElement;
+    parentElement: SimpleNode;
     firstNode: SimpleNode;
     lastNode: SimpleNode;
   } {
     let bounds: Bounds | null = component[BOUNDS];
 
     assert('object passed to getBounds must have the BOUNDS symbol as a property', bounds);
 
-    let parentElement = bounds.parentElement();
+    let parentElement = bounds.parentNode();
     let firstNode = bounds.firstNode();
     let lastNode = bounds.lastNode();
 

packages/@ember/-internals/glimmer/lib/syntax/in-element.ts

@@ -21,8 +21,13 @@
 
  `{{in-element}}` requires a single positional argument:
 
- - `destinationElement` -- the DOM element to render into. It must exist at the time
- of rendering.
+ - `destinationElement` -- the DOM element, `DocumentFragment`, or `ShadowRoot` to
+ render into. It must exist at the time of rendering.
+
+ When the destination is a `DocumentFragment`, appending the fragment to the DOM
+ moves its children into the new parent. Content rendered by `{{in-element}}`
+ follows that move: subsequent updates apply to the content in its new location,
+ and destroying the block removes the content from its new location.
 
  It also supports an optional named argument:
 

packages/@glimmer-workspace/integration-tests/lib/dom/simple-utils.ts

@@ -21,12 +21,12 @@ import { clearElement } from '@glimmer/util';
 import Serializer from '@simple-dom/serializer';
 import voidMap from '@simple-dom/void-map';
 
-export function toInnerHTML(parent: SimpleElement | SimpleDocumentFragment): string {
+export function toInnerHTML(parent: SimpleNode): string {
   const serializer = new Serializer(voidMap);
   return serializer.serializeChildren(parent);
 }
 
-export function toOuterHTML(parent: SimpleElement | SimpleDocumentFragment): string {
+export function toOuterHTML(parent: SimpleNode): string {
   const serializer = new Serializer(voidMap);
   return serializer.serialize(parent);
 }

packages/@glimmer-workspace/integration-tests/lib/suites.ts

@@ -7,6 +7,7 @@ export * from './suites/entry-point';
 export * from './suites/has-block';
 export * from './suites/has-block-params';
 export * from './suites/in-element';
+export * from './suites/in-element-document-fragment';
 export * from './suites/initial-render';
 export * from './suites/scope';
 export * from './suites/shadowing';