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diff --git a/spec/frontend/analytics/usage_trends/components/usage_trends_count_chart_spec.js b/spec/frontend/analytics/usage_trends/components/usage_trends_count_chart_spec.js
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+import { GlAlert } from '@gitlab/ui';
+import { GlLineChart } from '@gitlab/ui/dist/charts';
+import { createLocalVue, shallowMount } from '@vue/test-utils';
+import VueApollo from 'vue-apollo';
+import createMockApollo from 'helpers/mock_apollo_helper';
+import UsageTrendsCountChart from '~/analytics/usage_trends/components/usage_trends_count_chart.vue';
+import statsQuery from '~/analytics/usage_trends/graphql/queries/usage_count.query.graphql';
+import ChartSkeletonLoader from '~/vue_shared/components/resizable_chart/skeleton_loader.vue';
+import { mockQueryResponse, mockApolloResponse } from '../apollo_mock_data';
+import { mockCountsData1 } from '../mock_data';
+
+const localVue = createLocalVue();
+localVue.use(VueApollo);
+
+const loadChartErrorMessage = 'My load error message';
+const noDataMessage = 'My no data message';
+
+const queryResponseDataKey = 'usageTrendsMeasurements';
+const identifier = 'MOCK_QUERY';
+const mockQueryConfig = {
+  identifier,
+  title: 'Mock Query',
+  query: statsQuery,
+  loadError: 'Failed to load mock query data',
+};
+
+const mockChartConfig = {
+  loadChartErrorMessage,
+  noDataMessage,
+  chartTitle: 'Foo',
+  yAxisTitle: 'Bar',
+  xAxisTitle: 'Baz',
+  queries: [mockQueryConfig],
+};
+
+describe('UsageTrendsCountChart', () => {
+  let wrapper;
+  let queryHandler;
+
+  const createComponent = ({ responseHandler }) => {
+    return shallowMount(UsageTrendsCountChart, {
+      localVue,
+      apolloProvider: createMockApollo([[statsQuery, responseHandler]]),
+      propsData: { ...mockChartConfig },
+    });
+  };
+
+  afterEach(() => {
+    wrapper.destroy();
+    wrapper = null;
+  });
+
+  const findLoader = () => wrapper.find(ChartSkeletonLoader);
+  const findChart = () => wrapper.find(GlLineChart);
+  const findAlert = () => wrapper.find(GlAlert);
+
+  describe('while loading', () => {
+    beforeEach(() => {
+      queryHandler = mockQueryResponse({ key: queryResponseDataKey, loading: true });
+      wrapper = createComponent({ responseHandler: queryHandler });
+    });
+
+    it('requests data', () => {
+      expect(queryHandler).toBeCalledTimes(1);
+    });
+
+    it('displays the skeleton loader', () => {
+      expect(findLoader().exists()).toBe(true);
+    });
+
+    it('hides the chart', () => {
+      expect(findChart().exists()).toBe(false);
+    });
+
+    it('does not show an error', () => {
+      expect(findAlert().exists()).toBe(false);
+    });
+  });
+
+  describe('without data', () => {
+    beforeEach(() => {
+      queryHandler = mockQueryResponse({ key: queryResponseDataKey, data: [] });
+      wrapper = createComponent({ responseHandler: queryHandler });
+    });
+
+    it('renders an no data message', () => {
+      expect(findAlert().text()).toBe(noDataMessage);
+    });
+
+    it('hides the skeleton loader', () => {
+      expect(findLoader().exists()).toBe(false);
+    });
+
+    it('renders the chart', () => {
+      expect(findChart().exists()).toBe(false);
+    });
+  });
+
+  describe('with data', () => {
+    beforeEach(() => {
+      queryHandler = mockQueryResponse({ key: queryResponseDataKey, data: mockCountsData1 });
+      wrapper = createComponent({ responseHandler: queryHandler });
+    });
+
+    it('requests data', () => {
+      expect(queryHandler).toBeCalledTimes(1);
+    });
+
+    it('hides the skeleton loader', () => {
+      expect(findLoader().exists()).toBe(false);
+    });
+
+    it('renders the chart', () => {
+      expect(findChart().exists()).toBe(true);
+    });
+
+    it('passes the data to the line chart', () => {
+      expect(findChart().props('data')).toMatchSnapshot();
+    });
+
+    it('does not show an error', () => {
+      expect(findAlert().exists()).toBe(false);
+    });
+  });
+
+  describe('when fetching more data', () => {
+    const recordedAt = '2020-08-01';
+    describe('when the fetchMore query returns data', () => {
+      beforeEach(async () => {
+        const newData = [{ recordedAt, count: 5 }];
+        queryHandler = mockQueryResponse({
+          key: queryResponseDataKey,
+          data: mockCountsData1,
+          additionalData: newData,
+        });
+
+        wrapper = createComponent({ responseHandler: queryHandler });
+        await wrapper.vm.$nextTick();
+      });
+
+      it('requests data twice', () => {
+        expect(queryHandler).toBeCalledTimes(2);
+      });
+
+      it('passes the data to the line chart', () => {
+        expect(findChart().props('data')).toMatchSnapshot();
+      });
+    });
+
+    describe('when the fetchMore query throws an error', () => {
+      beforeEach(async () => {
+        queryHandler = jest.fn().mockResolvedValueOnce(
+          mockApolloResponse({
+            key: queryResponseDataKey,
+            data: mockCountsData1,
+            hasNextPage: true,
+          }),
+        );
+
+        wrapper = createComponent({ responseHandler: queryHandler });
+        jest
+          .spyOn(wrapper.vm.$apollo.queries[identifier], 'fetchMore')
+          .mockImplementation(jest.fn().mockRejectedValue());
+
+        await wrapper.vm.$nextTick();
+      });
+
+      it('calls fetchMore', () => {
+        expect(wrapper.vm.$apollo.queries[identifier].fetchMore).toHaveBeenCalledTimes(1);
+      });
+
+      it('show an error message', () => {
+        expect(findAlert().text()).toBe(loadChartErrorMessage);
+      });
+    });
+  });
+});