From 7ee54abf20aa4c52f0bc0fa862999a98f7ffbc3f Mon Sep 17 00:00:00 2001
From: Geoff Rich <geoff.s.rich@gmail.com>
Date: Wed, 21 Oct 2020 08:14:36 -0700
Subject: [PATCH] fix: treat shadow DOM elements as in the document (#298)

---
 src/__tests__/to-be-in-the-document.js | 20 +++++++++++++++++++-
 src/to-be-in-the-document.js           |  4 +++-
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/src/__tests__/to-be-in-the-document.js b/src/__tests__/to-be-in-the-document.js
index e6e9287c..6dae6ba3 100644
--- a/src/__tests__/to-be-in-the-document.js
+++ b/src/__tests__/to-be-in-the-document.js
@@ -2,12 +2,29 @@ import {HtmlElementTypeError} from '../utils'
 import document from './helpers/document'
 
 test('.toBeInTheDocument', () => {
+  const window = document.defaultView
+
+  window.customElements.define(
+    'custom-element',
+    class extends window.HTMLElement {
+      constructor() {
+        super()
+        this.attachShadow({mode: 'open'}).innerHTML =
+          '<div data-testid="custom-element-child"></div>'
+      }
+    },
+  )
+
   document.body.innerHTML = `
     <span data-testid="html-element"><span>Html Element</span></span>
-    <svg data-testid="svg-element"></svg>`
+    <svg data-testid="svg-element"></svg>
+    <custom-element data-testid="custom-element"></custom-element>`
 
   const htmlElement = document.querySelector('[data-testid="html-element"]')
   const svgElement = document.querySelector('[data-testid="svg-element"]')
+  const customElementChild = document
+    .querySelector('[data-testid="custom-element"]')
+    .shadowRoot.querySelector('[data-testid="custom-element-child"]')
   const detachedElement = document.createElement('div')
   const fakeElement = {thisIsNot: 'an html element'}
   const undefinedElement = undefined
@@ -15,6 +32,7 @@ test('.toBeInTheDocument', () => {
 
   expect(htmlElement).toBeInTheDocument()
   expect(svgElement).toBeInTheDocument()
+  expect(customElementChild).toBeInTheDocument()
   expect(detachedElement).not.toBeInTheDocument()
   expect(nullElement).not.toBeInTheDocument()
 
diff --git a/src/to-be-in-the-document.js b/src/to-be-in-the-document.js
index 8dcf5f50..765b3cf5 100644
--- a/src/to-be-in-the-document.js
+++ b/src/to-be-in-the-document.js
@@ -6,7 +6,9 @@ export function toBeInTheDocument(element) {
   }
 
   const pass =
-    element === null ? false : element.ownerDocument.contains(element)
+    element === null
+      ? false
+      : element.ownerDocument === element.getRootNode({composed: true})
 
   const errorFound = () => {
     return `expected document not to contain element, found ${this.utils.stringify(