Add latest changes from gitlab-org/gitlab@master

2 files changed, 61 insertions, 0 deletions

diff --git a/spec/frontend/helpers/keep_alive_component_helper.js b/spec/frontend/helpers/keep_alive_component_helper.js
new file mode 100644
index 00000000000..54f40bf9093
--- /dev/null
+++ b/spec/frontend/helpers/keep_alive_component_helper.js
@@ -0,0 +1,29 @@
+import Vue from 'vue';
+
+export function keepAlive(KeptAliveComponent) {
+  return Vue.extend({
+    components: {
+      KeptAliveComponent,
+    },
+    data() {
+      return {
+        view: 'KeptAliveComponent',
+      };
+    },
+    methods: {
+      async activate() {
+        this.view = 'KeptAliveComponent';
+        await this.$nextTick();
+      },
+      async deactivate() {
+        this.view = 'div';
+        await this.$nextTick();
+      },
+      async reactivate() {
+        await this.deactivate();
+        await this.activate();
+      },
+    },
+    template: `<keep-alive><component :is="view"></component></keep-alive>`,
+  });
+}
diff --git a/spec/frontend/helpers/keep_alive_component_helper_spec.js b/spec/frontend/helpers/keep_alive_component_helper_spec.js
new file mode 100644
index 00000000000..dcccc14f396
--- /dev/null
+++ b/spec/frontend/helpers/keep_alive_component_helper_spec.js
@@ -0,0 +1,32 @@
+import { mount } from '@vue/test-utils';
+import { keepAlive } from './keep_alive_component_helper';
+
+const component = {
+  template: '<div>Test Component</div>',
+};
+
+describe('keepAlive', () => {
+  let wrapper;
+
+  beforeEach(() => {
+    wrapper = mount(keepAlive(component));
+  });
+
+  afterEach(() => {
+    wrapper.destroy();
+  });
+
+  it('converts a component to a keep-alive component', async () => {
+    const { element } = wrapper.find(component);
+
+    await wrapper.vm.deactivate();
+    expect(wrapper.find(component).exists()).toBe(false);
+
+    await wrapper.vm.activate();
+
+    // assert that when the component is destroyed and re-rendered, the
+    // newly rendered component has the reference to the old component
+    // (i.e. the old component was deactivated and activated)
+    expect(wrapper.find(component).element).toBe(element);
+  });
+});