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// 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/widgets.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:leak_tracker_flutter_testing/leak_tracker_flutter_testing.dart';
void main() {
testWidgetsWithLeakTracking('setState can be called from build, initState, didChangeDependencies, and didUpdateWidget', (WidgetTester tester) async {
// Initial build.
await tester.pumpWidget(
const Directionality(
textDirection: TextDirection.ltr,
child: TestWidget(value: 1),
),
);
final _TestWidgetState state = tester.state(find.byType(TestWidget));
expect(state.calledDuringBuild, 1);
expect(state.calledDuringInitState, 1);
expect(state.calledDuringDidChangeDependencies, 1);
expect(state.calledDuringDidUpdateWidget, 0);
// Update Widget.
late Widget child;
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.ltr,
child: child = const TestWidget(value: 2),
),
);
expect(state.calledDuringBuild, 2); // Increased.
expect(state.calledDuringInitState, 1);
expect(state.calledDuringDidChangeDependencies, 1);
expect(state.calledDuringDidUpdateWidget, 1); // Increased.
// Build after state is dirty.
state.markNeedsBuild();
await tester.pump();
expect(state.calledDuringBuild, 3); // Increased.
expect(state.calledDuringInitState, 1);
expect(state.calledDuringDidChangeDependencies, 1);
expect(state.calledDuringDidUpdateWidget, 1);
// Change dependency.
await tester.pumpWidget(
Directionality(
textDirection: TextDirection.rtl, // Changed.
child: child,
),
);
expect(state.calledDuringBuild, 4); // Increased.
expect(state.calledDuringInitState, 1);
expect(state.calledDuringDidChangeDependencies, 2); // Increased.
expect(state.calledDuringDidUpdateWidget, 1);
});
}
class TestWidget extends StatefulWidget {
const TestWidget({super.key, required this.value});
final int value;
@override
State<TestWidget> createState() => _TestWidgetState();
}
class _TestWidgetState extends State<TestWidget> {
int calledDuringBuild = 0;
int calledDuringInitState = 0;
int calledDuringDidChangeDependencies = 0;
int calledDuringDidUpdateWidget = 0;
void markNeedsBuild() {
setState(() {
// Intentionally left empty.
});
}
@override
void initState() {
super.initState();
setState(() {
calledDuringInitState++;
});
}
@override
void didChangeDependencies() {
super.didChangeDependencies();
setState(() {
calledDuringDidChangeDependencies++;
});
}
@override
void didUpdateWidget(TestWidget oldWidget) {
super.didUpdateWidget(oldWidget);
setState(() {
calledDuringDidUpdateWidget++;
});
}
@override
Widget build(BuildContext context) {
setState(() {
calledDuringBuild++;
});
return SizedBox.expand(
child: Text('${widget.value}: ${Directionality.of(context)}'),
);
}
}