msglist [nfc]: Use ZulipBinding.instance.utcNow().toLocal() in DateText

Thanks Komyyy for this idea, which I took from PR zulip#1363.

Co-authored-by: Komyyy <[email protected]>

Author: 2 people

lib/widgets/message_list.dart

@@ -8,6 +8,7 @@ import 'package:intl/intl.dart' hide TextDirection;
 
 import '../api/model/model.dart';
 import '../generated/l10n/zulip_localizations.dart';
+import '../model/binding.dart';
 import '../model/database.dart';
 import '../model/message.dart';
 import '../model/message_list.dart';
@@ -1854,7 +1855,7 @@ class DateText extends StatelessWidget {
       formatHeaderDate(
         zulipLocalizations,
         DateTime.fromMillisecondsSinceEpoch(timestamp * 1000),
-        now: DateTime.now()));
+        now: ZulipBinding.instance.utcNow().toLocal()));
   }
 }
 

test/widgets/message_list_test.dart

@@ -2,6 +2,7 @@ import 'dart:convert';
 import 'dart:io';
 
 import 'package:checks/checks.dart';
+import 'package:clock/clock.dart';
 import 'package:collection/collection.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
@@ -1654,8 +1655,16 @@ void main() {
     ];
     for (final (dateTime, expected) in testCases) {
       test('$dateTime returns $expected', () {
-        check(formatHeaderDate(zulipLocalizations, DateTime.parse(dateTime), now: now))
-          .equals(expected);
+        addTearDown(testBinding.reset);
+
+        withClock(Clock.fixed(now), () {
+          check(formatHeaderDate(
+            zulipLocalizations,
+            DateTime.parse(dateTime),
+            now: testBinding.utcNow().toLocal(),
+          ))
+            .equals(expected);
+        });
       });
     }
   });