add tests for Pager

tests/unit/components/Pager.spec.js

@@ -0,0 +1,33 @@
+import { expect } from 'chai'
+import sinon from 'sinon'
+import { mount, shallowMount } from '@vue/test-utils'
+import Pager from '@/components/Pager.vue'
+
+describe('Pager.vue', () => {
+  afterEach(() => {
+    sinon.restore()
+  })
+
+  it('emits input event with a page', async () => {
+    const wrapper = mount(Pager, { propsData: {
+      pageCount: 5
+    }})
+
+    // click on 'next page' link 
+    await wrapper.find('.paginator-next').trigger('click')
+    expect(wrapper.emitted('input')[0]).to.eql([2])
+
+    // click on the link to page 3 (it has index 2)
+    await wrapper.findAll('.paginator-page-link').at(2).trigger('click')
+    expect(wrapper.emitted('input')[1]).to.eql([3])
+  })
+
+  it('changes the page when value is changed', async () => {
+    const wrapper = mount(Pager, { propsData: {
+      pageCount: 5
+    }})
+
+    await wrapper.setProps({ value: 5 })
+    expect(wrapper.emitted('input')[0]).to.eql([5])
+  })
+})