Adds message forwarding

ts/test-both/state/ducks/linkPreviews_test.ts

@@ -0,0 +1,48 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { assert } from 'chai';
+
+import {
+  actions,
+  getEmptyState,
+  reducer,
+} from '../../../state/ducks/linkPreviews';
+import { LinkPreviewType } from '../../../types/message/LinkPreviews';
+
+describe('both/state/ducks/linkPreviews', () => {
+  function getMockLinkPreview(): LinkPreviewType {
+    return {
+      title: 'Hello World',
+      domain: 'signal.org',
+      url: 'https://www.signal.org',
+      isStickerPack: false,
+    };
+  }
+
+  describe('addLinkPreview', () => {
+    const { addLinkPreview } = actions;
+
+    it('updates linkPreview', () => {
+      const state = getEmptyState();
+      const linkPreview = getMockLinkPreview();
+      const nextState = reducer(state, addLinkPreview(linkPreview));
+
+      assert.strictEqual(nextState.linkPreview, linkPreview);
+    });
+  });
+
+  describe('removeLinkPreview', () => {
+    const { removeLinkPreview } = actions;
+
+    it('removes linkPreview', () => {
+      const state = {
+        ...getEmptyState(),
+        linkPreview: getMockLinkPreview(),
+      };
+      const nextState = reducer(state, removeLinkPreview());
+
+      assert.isUndefined(nextState.linkPreview);
+    });
+  });
+});