Testing a Chart.js component with Vue test utils throws a window.matchMedia error - vue.js

Question

I'm trying to write Mocha/Chai tests for a Vue component which utilizes Chart.js. All tests pass, but I then get this error:
C:\repos\security-center-frontend-2\security-center-frontend\node_modules\mocha\lib\runner.js:726
err.uncaught = true;
^
TypeError: Cannot create property 'uncaught' on string
'window.matchMedia not found! Make sure you're using a polyfill.'
I think that this has to do with the way Vue test utils represent the window object, and that I should somehow stub it, but am not sure of the proper syntax.
My component:
<template>
<card>
<template slot="header">
<h4 v-if="$slots.title || title" class="card-title">
<slot name="title">
{{title}}
</slot>
</h4>
<p class="card-category">
<slot name="subTitle">
{{subTitle}}
</slot>
</p>
</template>
<div>
<div :id="chartId" class="ct-chart"></div>
<div class="footer">
<div class="chart-legend">
<slot name="legend"></slot>
</div>
<hr>
<div class="stats">
<slot name="footer"></slot>
</div>
<div class="pull-right">
</div>
</div>
</div>
</card>
</template>
<script>
import Card from './Card.vue';
export default {
name: 'chart-card',
components: {
Card
},
props: {
footerText: {
type: String,
default: ''
},
title: {
type: String,
default: ''
},
subTitle: {
type: String,
default: ''
},
chartType: {
type: String,
default: 'Line' // Line | Pie | Bar
},
chartOptions: {
type: Object,
default: () => {
return {};
}
},
chartData: {
type: Object,
default: () => {
return {
labels: [],
series: []
};
}
}
},
data () {
return {
chartId: 'no-id'
};
},
methods: {
/***
* Initializes the chart by merging the chart options sent via props and the default chart options
*/
initChart (Chartist) {
const chartIdQuery = `#${this.chartId}`;
Chartist[this.chartType](
chartIdQuery,
this.chartData,
this.chartOptions
);
},
/***
* Assigns a random id to the chart
*/
updateChartId () {
const currentTime = new Date().getTime().toString();
const randomInt = this.getRandomInt(0, currentTime);
this.chartId = `div_${randomInt}`;
},
getRandomInt (min, max) {
return Math.floor(Math.random() * (max - min + 1)) + min;
}
},
mounted () {
this.updateChartId();
import('chartist').then((Chartist) => {
let ChartistLib = Chartist.default || Chartist;
this.$nextTick(() => {
this.initChart(ChartistLib);
});
});
}
};
</script>
<style>
</style>
My tests:
import { expect } from 'chai';
import { mount } from '#vue/test-utils';
import ChartCard from '#/components/Cards/ChartCard.vue';
describe('ChartCard.vue', () => {
it('Has a title', () => {
const wrapper = mount(ChartCard);
wrapper.setProps({title: 'test title'});
expect(wrapper.contains('.card-title')).to.be.true;
});
it('Displays passed title', () => {
const wrapper = mount(ChartCard);
wrapper.setProps({title: 'test title'});
expect(wrapper.text()).to.include('test title');
});
});