Discriminator in username

ts/test-node/util/Username_test.ts

@@ -0,0 +1,82 @@
+// 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.strictEqual(getUsernameFromSearch('use'), 'use');
+      assert.strictEqual(
+        getUsernameFromSearch('username9012345678901234567'),
+        'username9012345678901234567'
+      );
+    });
+
+    it('matches valid username searches', () => {
+      assert.strictEqual(getUsernameFromSearch('username_34'), 'username_34');
+      assert.strictEqual(getUsernameFromSearch('u5ername'), 'u5ername');
+      assert.strictEqual(getUsernameFromSearch('username.12'), 'username.12');
+      assert.strictEqual(getUsernameFromSearch('user'), 'user');
+      assert.strictEqual(
+        getUsernameFromSearch('username901234567890123456'),
+        'username901234567890123456'
+      );
+    });
+
+    it('matches valid and invalid usernames with @ prefix', () => {
+      assert.strictEqual(getUsernameFromSearch('@username!'), 'username!');
+      assert.strictEqual(getUsernameFromSearch('@1username'), '1username');
+      assert.strictEqual(getUsernameFromSearch('@username_34'), 'username_34');
+      assert.strictEqual(getUsernameFromSearch('@username.34'), 'username.34');
+      assert.strictEqual(getUsernameFromSearch('@u5ername'), 'u5ername');
+    });
+
+    it('matches valid and invalid usernames with @ suffix', () => {
+      assert.strictEqual(getUsernameFromSearch('username!@'), 'username!');
+      assert.strictEqual(getUsernameFromSearch('1username@'), '1username');
+      assert.strictEqual(getUsernameFromSearch('username_34@'), 'username_34');
+      assert.strictEqual(getUsernameFromSearch('username.34@'), 'username.34');
+      assert.strictEqual(getUsernameFromSearch('u5ername@'), 'u5ername');
+    });
+
+    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'));
+    });
+  });
+
+  describe('isValidUsername', () => {
+    const { isValidUsername } = Username;
+
+    it('does not match invalid username searches', () => {
+      assert.isFalse(isValidUsername('username!'));
+      assert.isFalse(isValidUsername('1username'));
+      assert.isFalse(isValidUsername('u'));
+      assert.isFalse(isValidUsername('username9012345678901234567890123'));
+      assert.isFalse(isValidUsername('username.abc'));
+    });
+
+    it('matches valid usernames', () => {
+      assert.isTrue(isValidUsername('username_34'));
+      assert.isTrue(isValidUsername('u5ername'));
+      assert.isTrue(isValidUsername('_username'));
+      assert.isTrue(isValidUsername('use'));
+      assert.isTrue(isValidUsername('username901234567890123456789012'));
+      assert.isTrue(isValidUsername('username.0123'));
+    });
+
+    it('does not match valid and invalid usernames with @ prefix or suffix', () => {
+      assert.isFalse(isValidUsername('@username_34'));
+      assert.isFalse(isValidUsername('@1username'));
+      assert.isFalse(isValidUsername('username_34@'));
+      assert.isFalse(isValidUsername('1username@'));
+    });
+  });
+});