From 381e745ec8334aaf69f5fad48e3ad50a5fc24158 Mon Sep 17 00:00:00 2001
From: Tom Byers <tombaromba@gmail.com>
Date: Wed, 24 Jul 2019 17:47:43 +0100
Subject: [PATCH] Make helper plug gap in JSDOM's DOM API

Errors fired from JSDOM showed it doesn't support
`window.scrollTo` (or `window.scroll` for that
matter).

This stubs it, to the extent that our use (jQuery
really) of it works.
---
 tests/javascripts/support/helpers.js | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/tests/javascripts/support/helpers.js b/tests/javascripts/support/helpers.js
index 5d3df2c22..9e859e44a 100644
--- a/tests/javascripts/support/helpers.js
+++ b/tests/javascripts/support/helpers.js
@@ -228,6 +228,7 @@ class WindowMock {
     };
     this._jest = jest;
     this._setSpies();
+    this._plugJSDOM();
   }
 
   get top () {
@@ -260,6 +261,27 @@ class WindowMock {
 
   }
 
+  _plugJSDOM () {
+
+    const self = this;
+
+    // JSDOM doesn't support .scrollTo
+    window.scrollTo = function () {
+      let y;
+
+      // data sent as props in an object
+      if (arguments.length === 1) {
+        y = arguments[0].y;
+      } else {
+        y = arguments[1];
+      }
+
+      self.scrollTo(y);
+
+    };
+
+  }
+
   setHeightTo (height) {
 
     window.innerHeight = height;