1 files changed, 152 insertions, 0 deletions
diff --git a/spec/frontend/boards/components/sidebar/board_sidebar_milestone_select_spec.js b/spec/frontend/boards/components/sidebar/board_sidebar_milestone_select_spec.js
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index 00000000000..74d88d9f34c
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+++ b/spec/frontend/boards/components/sidebar/board_sidebar_milestone_select_spec.js
@@ -0,0 +1,152 @@
+import { shallowMount } from '@vue/test-utils';
+import { GlLoadingIcon } from '@gitlab/ui';
+import { mockMilestone as TEST_MILESTONE } from 'jest/boards/mock_data';
+import BoardSidebarMilestoneSelect from '~/boards/components/sidebar/board_sidebar_milestone_select.vue';
+import BoardEditableItem from '~/boards/components/sidebar/board_editable_item.vue';
+import { createStore } from '~/boards/stores';
+import createFlash from '~/flash';
+
+const TEST_ISSUE = { id: 'gid://gitlab/Issue/1', iid: 9, referencePath: 'h/b#2' };
+
+jest.mock('~/flash');
+
+describe('~/boards/components/sidebar/board_sidebar_milestone_select.vue', () => {
+  let wrapper;
+  let store;
+
+  afterEach(() => {
+    wrapper.destroy();
+    store = null;
+    wrapper = null;
+  });
+
+  const createWrapper = ({ milestone = null } = {}) => {
+    store = createStore();
+    store.state.issues = { [TEST_ISSUE.id]: { ...TEST_ISSUE, milestone } };
+    store.state.activeId = TEST_ISSUE.id;
+
+    wrapper = shallowMount(BoardSidebarMilestoneSelect, {
+      store,
+      provide: {
+        canUpdate: true,
+      },
+      data: () => ({
+        milestones: [TEST_MILESTONE],
+      }),
+      stubs: {
+        'board-editable-item': BoardEditableItem,
+      },
+      mocks: {
+        $apollo: {
+          loading: false,
+        },
+      },
+    });
+  };
+
+  const findCollapsed = () => wrapper.find('[data-testid="collapsed-content"]');
+  const findLoader = () => wrapper.find(GlLoadingIcon);
+  const findDropdownItem = () => wrapper.find('[data-testid="milestone-item"]');
+  const findUnsetMilestoneItem = () => wrapper.find('[data-testid="no-milestone-item"]');
+  const findNoMilestonesFoundItem = () => wrapper.find('[data-testid="no-milestones-found"]');
+
+  it('renders "None" when no milestone is selected', () => {
+    createWrapper();
+
+    expect(findCollapsed().text()).toBe('None');
+  });
+
+  it('renders milestone title when set', () => {
+    createWrapper({ milestone: TEST_MILESTONE });
+
+    expect(findCollapsed().text()).toContain(TEST_MILESTONE.title);
+  });
+
+  it('shows loader while Apollo is loading', async () => {
+    createWrapper({ milestone: TEST_MILESTONE });
+
+    expect(findLoader().exists()).toBe(false);
+
+    wrapper.vm.$apollo.loading = true;
+    await wrapper.vm.$nextTick();
+
+    expect(findLoader().exists()).toBe(true);
+  });
+
+  it('shows message when error or no milestones found', async () => {
+    createWrapper();
+
+    wrapper.setData({ milestones: [] });
+    await wrapper.vm.$nextTick();
+
+    expect(findNoMilestonesFoundItem().text()).toBe('No milestones found');
+  });
+
+  describe('when milestone is selected', () => {
+    beforeEach(async () => {
+      createWrapper();
+
+      jest.spyOn(wrapper.vm, 'setActiveIssueMilestone').mockImplementation(() => {
+        store.state.issues[TEST_ISSUE.id].milestone = TEST_MILESTONE;
+      });
+      findDropdownItem().vm.$emit('click');
+      await wrapper.vm.$nextTick();
+    });
+
+    it('collapses sidebar and renders selected milestone', () => {
+      expect(findCollapsed().isVisible()).toBe(true);
+      expect(findCollapsed().text()).toContain(TEST_MILESTONE.title);
+    });
+
+    it('commits change to the server', () => {
+      expect(wrapper.vm.setActiveIssueMilestone).toHaveBeenCalledWith({
+        milestoneId: TEST_MILESTONE.id,
+        projectPath: 'h/b',
+      });
+    });
+  });
+
+  describe('when milestone is set to "None"', () => {
+    beforeEach(async () => {
+      createWrapper({ milestone: TEST_MILESTONE });
+
+      jest.spyOn(wrapper.vm, 'setActiveIssueMilestone').mockImplementation(() => {
+        store.state.issues[TEST_ISSUE.id].milestone = null;
+      });
+      findUnsetMilestoneItem().vm.$emit('click');
+      await wrapper.vm.$nextTick();
+    });
+
+    it('collapses sidebar and renders "None"', () => {
+      expect(findCollapsed().isVisible()).toBe(true);
+      expect(findCollapsed().text()).toBe('None');
+    });
+
+    it('commits change to the server', () => {
+      expect(wrapper.vm.setActiveIssueMilestone).toHaveBeenCalledWith({
+        milestoneId: null,
+        projectPath: 'h/b',
+      });
+    });
+  });
+
+  describe('when the mutation fails', () => {
+    const testMilestone = { id: '1', title: 'Former milestone' };
+
+    beforeEach(async () => {
+      createWrapper({ milestone: testMilestone });
+
+      jest.spyOn(wrapper.vm, 'setActiveIssueMilestone').mockImplementation(() => {
+        throw new Error(['failed mutation']);
+      });
+      findDropdownItem().vm.$emit('click');
+      await wrapper.vm.$nextTick();
+    });
+
+    it('collapses sidebar and renders former milestone', () => {
+      expect(findCollapsed().isVisible()).toBe(true);
+      expect(findCollapsed().text()).toContain(testMilestone.title);
+      expect(createFlash).toHaveBeenCalled();
+    });
+  });
+});