autocomplete test [nfc]: Bring details next to details in end-to-end test

This way it's possible to look at the expected results at the end of
this test and compare them with the test data that leads to those
results, without scanning past a lot of other code that isn't related
to why these particular results are the right answers.

Author: gnprice

test/model/autocomplete_test.dart

@@ -575,46 +575,11 @@ void main() {
     });
 
     test('final results end-to-end', () async {
-      // The order should be:
-      // 1. Users most recent in the current topic/stream.
-      // 2. Users most recent in the DM conversations.
-
-      final stream = eg.stream();
-      const topic = 'topic';
-      final topicNarrow = TopicNarrow(stream.streamId, topic);
-
-      final users = [
-        eg.user(userId: 1, fullName: 'User One'),
-        eg.user(userId: 2, fullName: 'User Two'),
-        eg.user(userId: 3, fullName: 'User Three'),
-        eg.user(userId: 4, fullName: 'User Four'),
-        eg.user(userId: 5, fullName: 'User Five'),
-      ];
-
-      final dmConversations = [
-        RecentDmConversation(userIds: [4],    maxMessageId: 300),
-        RecentDmConversation(userIds: [1],    maxMessageId: 200),
-        RecentDmConversation(userIds: [1, 2], maxMessageId: 100),
-      ];
-
-      StreamMessage streamMessage({required int id, required int senderId, String? topic}) =>
-        eg.streamMessage(id: id, sender: users[senderId-1], topic: topic, stream: stream);
-
-      final messages = [
-        streamMessage(id: 50, senderId: 1, topic: topic),
-        streamMessage(id: 60, senderId: 5),
-      ];
-
-      Future<void> prepareStore() async {
-        await prepare(users: users, dmConversations: dmConversations,
-          messages: messages);
-      }
-
-      Future<void> fetchInitialMessagesIn(Narrow narrow) async {
+      Future<void> fetchInitialMessagesIn(Narrow narrow, List<Message> messages) async {
         final connection = store.connection as FakeApiConnection;
         connection.prepare(json: newestResult(
           foundOldest: false,
-          messages: messages.where((m) => m.topic == topic).toList(),
+          messages: messages,
         ).toJson());
         final messageList = MessageListView.init(store: store, narrow: narrow);
         await messageList.fetchInitial();
@@ -634,11 +599,38 @@ void main() {
         return results;
       }
 
-      await prepareStore();
-      await fetchInitialMessagesIn(topicNarrow);
+      final stream = eg.stream();
+      const topic = 'topic';
+      final topicNarrow = TopicNarrow(stream.streamId, topic);
+
+      final users = [
+        eg.user(userId: 1, fullName: 'User One'),
+        eg.user(userId: 2, fullName: 'User Two'),
+        eg.user(userId: 3, fullName: 'User Three'),
+        eg.user(userId: 4, fullName: 'User Four'),
+        eg.user(userId: 5, fullName: 'User Five'),
+      ];
+
+      final messages = [
+        eg.streamMessage(id: 50, sender: users[1-1], stream: stream, topic: topic),
+        eg.streamMessage(id: 60, sender: users[5-1], stream: stream),
+      ];
+
+      await prepare(users: users, messages: messages, dmConversations: [
+        RecentDmConversation(userIds: [4],    maxMessageId: 300),
+        RecentDmConversation(userIds: [1],    maxMessageId: 200),
+        RecentDmConversation(userIds: [1, 2], maxMessageId: 100),
+      ]);
+      await fetchInitialMessagesIn(topicNarrow,
+        messages.where((m) => m.topic == topic).toList());
+
       // Check the ranking of the full list of users.
+      // The order should be:
+      // 1. Users most recent in the current topic/stream.
+      // 2. Users most recent in the DM conversations.
       check(await getResults(topicNarrow, MentionAutocompleteQuery('')))
         .deepEquals([1, 5, 4, 2, 3]);
+
       // Check the ranking applies also to results filtered by a query.
       check(await getResults(topicNarrow, MentionAutocompleteQuery('t')))
         .deepEquals([2, 3]);