1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'package:flutter/scheduler.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter_test/flutter_test.dart';
import 'common.dart';
void main() {
WidgetsFlutterBinding.ensureInitialized();
initTimelineTests();
test('Widgets with updated keys produce well formed timelines', () async {
await runFrame(() { runApp(const TestRoot()); });
await SchedulerBinding.instance.endOfFrame;
debugProfileBuildsEnabled = true;
await runFrame(() {
TestRoot.state.updateKey();
});
int buildCount = 0;
for (final TimelineEvent event in await fetchTimelineEvents()) {
if (event.json!['name'] == 'BUILD') {
final String ph = event.json!['ph'] as String;
if (ph == 'B') {
buildCount++;
} else if (ph == 'E') {
buildCount--;
}
}
}
expect(buildCount, 0);
debugProfileBuildsEnabled = false;
}, skip: isBrowser); // [intended] uses dart:isolate and io.
}
class TestRoot extends StatefulWidget {
const TestRoot({super.key});
static late TestRootState state;
@override
State<TestRoot> createState() => TestRootState();
}
class TestRootState extends State<TestRoot> {
final Key _globalKey = GlobalKey();
Key _localKey = UniqueKey();
@override
void initState() {
super.initState();
TestRoot.state = this;
}
void updateKey() {
setState(() {
_localKey = UniqueKey();
});
}
@override
Widget build(BuildContext context) {
return Center(
key: _localKey,
child: SizedBox(
key: _globalKey,
width: 100,
height: 100,
),
);
}
}