feat: 🎸 implement live relative datetime component (#1080)

addons/core/tests/integration/components/relative-datetime-live-test.js

@@ -0,0 +1,38 @@
+import { module, test } from 'qunit';
+import { setupRenderingTest } from 'ember-qunit';
+import { render } from '@ember/test-helpers';
+import { hbs } from 'ember-cli-htmlbars';
+
+module('Integration | Component | relative-datetime-live', function (hooks) {
+  setupRenderingTest(hooks);
+
+  test('it renders a relative datetime', async function (assert) {
+    assert.expect(6);
+
+    const now = Date.now();
+
+    this.date = now - 10 * 1000;
+    await render(hbs`<RelativeDatetimeLive @date={{this.date}} />`);
+    assert.dom(this.element).hasText('10 seconds ago');
+
+    this.date = now - 10 * 60 * 1000;
+    await render(hbs`<RelativeDatetimeLive @date={{this.date}} />`);
+    assert.dom(this.element).hasText('10 minutes ago');
+
+    this.date = now - 10 * 60 * 60 * 1000;
+    await render(hbs`<RelativeDatetimeLive @date={{this.date}} />`);
+    assert.dom(this.element).hasText('10 hours ago');
+
+    this.date = now - 10 * 24 * 60 * 60 * 1000;
+    await render(hbs`<RelativeDatetimeLive @date={{this.date}} />`);
+    assert.dom(this.element).hasText('10 days ago');
+
+    this.date = now - 10 * 31 * 24 * 60 * 60 * 1000;
+    await render(hbs`<RelativeDatetimeLive @date={{this.date}} />`);
+    assert.dom(this.element).hasText('10 months ago');
+
+    this.date = now - 10 * 12 * 31 * 24 * 60 * 60 * 1000;
+    await render(hbs`<RelativeDatetimeLive @date={{this.date}} />`);
+    assert.dom(this.element).hasText('10 years ago');
+  });
+});