flutter_flutter/packages/flutter/test/animation/animation_sheet_test.dart

// 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.

// This file is run as part of a reduced test set in CI on Mac and Windows
// machines.
@Tags(<String>['reduced-test-set'])
library;

import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';

void main() {
  /*
   * Here lies tests for packages/flutter_test/lib/src/animation_sheet.dart
   * because [matchesGoldenFile] does not use Skia Gold in its native package.
   */

  testWidgets(
    'recording disposes images',
    (WidgetTester tester) async {
      final builder = AnimationSheetBuilder(frameSize: _DecuplePixels.size);
      addTearDown(builder.dispose);

      await tester.pumpFrames(
        builder.record(const _DecuplePixels(Duration(seconds: 1))),
        const Duration(milliseconds: 200),
        const Duration(milliseconds: 100),
      );
    },
    skip: isBrowser, // [intended] https://github.com/flutter/flutter/issues/56001
  );

  testWidgets(
    'correctly records frames using collate',
    (WidgetTester tester) async {
      final builder = AnimationSheetBuilder(frameSize: _DecuplePixels.size);
      addTearDown(builder.dispose);

      await tester.pumpFrames(
        builder.record(const _DecuplePixels(Duration(seconds: 1))),
        const Duration(milliseconds: 200),
        const Duration(milliseconds: 100),
      );

      await tester.pumpFrames(
        builder.record(const _DecuplePixels(Duration(seconds: 1)), recording: false),
        const Duration(milliseconds: 200),
        const Duration(milliseconds: 100),
      );

      await tester.pumpFrames(
        builder.record(const _DecuplePixels(Duration(seconds: 1))),
        const Duration(milliseconds: 400),
        const Duration(milliseconds: 100),
      );

      await expectLater(
        builder.collate(5),
        matchesGoldenFile('test.animation_sheet_builder.collate.png'),
      );
    },
    skip: isBrowser, // [intended] https://github.com/flutter/flutter/issues/56001
  ); // https://github.com/flutter/flutter/issues/56001

  testWidgets(
    'use allLayers to record out-of-subtree contents',
    (WidgetTester tester) async {
      final builder = AnimationSheetBuilder(frameSize: const Size(8, 2), allLayers: true);
      addTearDown(builder.dispose);

      // The `record` (sized 8, 2) is placed on top of `_DecuplePixels`
      // (sized 12, 3), aligned at its top left.
      await tester.pumpFrames(
        Directionality(
          textDirection: TextDirection.ltr,
          child: Stack(
            children: <Widget>[
              const _DecuplePixels(Duration(seconds: 1)),
              Align(alignment: Alignment.topLeft, child: builder.record(Container())),
            ],
          ),
        ),
        const Duration(milliseconds: 600),
        const Duration(milliseconds: 100),
      );

      await expectLater(
        builder.collate(5),
        matchesGoldenFile('test.animation_sheet_builder.out_of_tree.png'),
      );
    },
    skip: isBrowser, // [intended] https://github.com/flutter/flutter/issues/56001
  );
}

// An animation of a yellow pixel moving from left to right, in a container of
// (10, 1) with a 1-pixel-wide black border.
class _DecuplePixels extends StatefulWidget {
  const _DecuplePixels(this.duration);

  static const Size size = Size(12, 3);

  final Duration duration;

  @override
  State<StatefulWidget> createState() => _DecuplePixelsState();
}

class _DecuplePixelsState extends State<_DecuplePixels>
    with SingleTickerProviderStateMixin<_DecuplePixels> {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(duration: widget.duration, vsync: this);
    _controller.repeat();
  }

  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _controller.view,
      builder: (BuildContext context, Widget? child) {
        return CustomPaint(painter: _PaintDecuplePixels(_controller.value));
      },
    );
  }
}

class _PaintDecuplePixels extends CustomPainter {
  _PaintDecuplePixels(this.value);

  final double value;

  @override
  bool shouldRepaint(_PaintDecuplePixels oldDelegate) {
    return oldDelegate.value != value;
  }

  @override
  void paint(Canvas canvas, Size size) {
    canvas.save();
    final Rect rect = RectTween(
      begin: const Rect.fromLTWH(1, 1, 1, 1),
      end: const Rect.fromLTWH(11, 1, 1, 1),
    ).transform(value)!;
    canvas.drawRect(rect, Paint()..color = Colors.yellow);
    final black = Paint()..color = Colors.black;
    canvas
      // Top border
      ..drawRect(const Rect.fromLTRB(0, 0, 12, 1), black)
      // Bottom border
      ..drawRect(const Rect.fromLTRB(0, 2, 12, 3), black)
      // Left border
      ..drawRect(const Rect.fromLTRB(0, 0, 1, 3), black)
      // Right border
      ..drawRect(const Rect.fromLTRB(11, 0, 12, 3), black);

    canvas.restore();
  }
}