Fix SMS-only check for unregistered convo

ts/test-both/util/isConversationSMSOnly_test.ts

@@ -6,14 +6,32 @@ import { assert } from 'chai';
 import { isConversationSMSOnly } from '../../util/isConversationSMSOnly';
 
 describe('isConversationSMSOnly', () => {
-  it('returns false if passed an undefined discoveredUnregisteredAt', () => {
-    assert.isFalse(isConversationSMSOnly({}));
+  it('returns false if passed an undefined type', () => {
     assert.isFalse(
-      isConversationSMSOnly({ discoveredUnregisteredAt: undefined })
+      isConversationSMSOnly({
+        type: undefined,
+      })
     );
   });
 
   ['direct', 'private'].forEach(type => {
+    it('returns false if passed an undefined discoveredUnregisteredAt', () => {
+      assert.isFalse(
+        isConversationSMSOnly({ type, discoveredUnregisteredAt: undefined })
+      );
+    });
+
+    it('returns true if passed a very old discoveredUnregisteredAt', () => {
+      assert.isTrue(
+        isConversationSMSOnly({
+          type,
+          e164: 'e164',
+          uuid: 'uuid',
+          discoveredUnregisteredAt: 1,
+        })
+      );
+    });
+
     it(`returns true if passed a time fewer than 6 hours ago and is ${type}`, () => {
       assert.isTrue(
         isConversationSMSOnly({

ts/util/isConversationSMSOnly.ts

@@ -1,8 +1,6 @@
 // Copyright 2021 Signal Messenger, LLC
 // SPDX-License-Identifier: AGPL-3.0-only
 
-import { isConversationUnregistered } from './isConversationUnregistered';
-
 export type MinimalConversationType = Readonly<{
   type?: string;
   e164?: string;
@@ -23,5 +21,5 @@ export function isConversationSMSOnly(
     return true;
   }
 
-  return isConversationUnregistered(conversation);
+  return conversation.discoveredUnregisteredAt !== undefined;
 }