More permissive username search

ts/test-electron/util/Username_test.ts

@@ -0,0 +1,34 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { assert } from 'chai';
+
+import * as Username from '../../util/Username';
+
+describe('Username', () => {
+  describe('getUsernameFromSearch', () => {
+    const { getUsernameFromSearch } = Username;
+
+    it('matches invalid username searches', () => {
+      assert.isUndefined(getUsernameFromSearch('us'));
+      assert.isUndefined(getUsernameFromSearch('123'));
+    });
+
+    it('matches partial username searches without discriminator', () => {
+      assert.strictEqual(getUsernameFromSearch('use'), 'use');
+      assert.strictEqual(getUsernameFromSearch('use.'), 'use.');
+    });
+
+    it('matches valid username searches', () => {
+      assert.strictEqual(getUsernameFromSearch('username.12'), 'username.12');
+      assert.strictEqual(getUsernameFromSearch('xyz.568'), 'xyz.568');
+    });
+
+    it('does not match something that looks like a phone number', () => {
+      assert.isUndefined(getUsernameFromSearch('+'));
+      assert.isUndefined(getUsernameFromSearch('2223'));
+      assert.isUndefined(getUsernameFromSearch('+3'));
+      assert.isUndefined(getUsernameFromSearch('+234234234233'));
+    });
+  });
+});