fade_in_image_test.dart 19.8 KB
Newer Older
Ian Hickson's avatar
Ian Hickson committed
1
// Copyright 2014 The Flutter Authors. All rights reserved.
2 3 4
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

5
import 'dart:async';
6
import 'dart:typed_data';
7 8 9 10
import 'dart:ui' as ui;

import 'package:flutter/widgets.dart';
import 'package:flutter_test/flutter_test.dart';
11 12

import '../image_data.dart';
13
import '../painting/image_test_utils.dart';
14

15 16 17 18 19 20 21 22
const Duration animationDuration = Duration(milliseconds: 50);

class FadeInImageParts {
  const FadeInImageParts(this.fadeInImageElement, this.placeholder, this.target)
      : assert(fadeInImageElement != null),
        assert(target != null);

  final ComponentElement fadeInImageElement;
23
  final FadeInImageElements? placeholder;
24 25
  final FadeInImageElements target;

26 27
  State? get state {
    StatefulElement? animatedFadeOutFadeInElement;
28 29
    fadeInImageElement.visitChildren((Element child) {
      expect(animatedFadeOutFadeInElement, isNull);
30
      animatedFadeOutFadeInElement = child as StatefulElement;
31 32
    });
    expect(animatedFadeOutFadeInElement, isNotNull);
33
    return animatedFadeOutFadeInElement!.state;
34 35
  }

36 37
  Element? get semanticsElement {
    Element? result;
38
    fadeInImageElement.visitChildren((Element child) {
39
      if (child.widget is Semantics) {
40
        result = child;
41
      }
42 43 44 45 46 47
    });
    return result;
  }
}

class FadeInImageElements {
48
  const FadeInImageElements(this.rawImageElement);
49 50 51

  final Element rawImageElement;

52
  RawImage get rawImage => rawImageElement.widget as RawImage;
53
  double get opacity => rawImage.opacity?.value ?? 1.0;
54
  BoxFit? get fit => rawImage.fit;
55 56
}

57
class LoadTestImageProvider extends ImageProvider<Object> {
58 59 60 61
  LoadTestImageProvider(this.provider);

  final ImageProvider provider;

62 63
  ImageStreamCompleter testLoad(Object key, DecoderBufferCallback decode) {
    return provider.loadBuffer(key, decode);
64 65 66
  }

  @override
67 68
  Future<Object> obtainKey(ImageConfiguration configuration) {
    throw UnimplementedError();
69 70 71
  }

  @override
72 73
  ImageStreamCompleter load(Object key, DecoderCallback decode) {
    throw UnimplementedError();
74 75 76
  }
}

77 78 79
FadeInImageParts findFadeInImage(WidgetTester tester) {
  final List<FadeInImageElements> elements = <FadeInImageElements>[];
  final Iterable<Element> rawImageElements = tester.elementList(find.byType(RawImage));
80
  ComponentElement? fadeInImageElement;
81
  for (final Element rawImageElement in rawImageElements) {
82
    rawImageElement.visitAncestorElements((Element ancestor) {
83
      if (ancestor.widget is FadeInImage) {
84
        if (fadeInImageElement == null) {
85
          fadeInImageElement = ancestor as ComponentElement;
86 87 88 89 90 91 92 93
        } else {
          expect(fadeInImageElement, same(ancestor));
        }
        return false;
      }
      return true;
    });
    expect(fadeInImageElement, isNotNull);
94
    elements.add(FadeInImageElements(rawImageElement));
95 96
  }
  if (elements.length == 2) {
97
    return FadeInImageParts(fadeInImageElement!, elements.last, elements.first);
98 99
  } else {
    expect(elements, hasLength(1));
100
    return FadeInImageParts(fadeInImageElement!, null, elements.first);
101 102 103
  }
}

104
Future<void> main() async {
105 106 107
  // These must run outside test zone to complete
  final ui.Image targetImage = await createTestImage();
  final ui.Image placeholderImage = await createTestImage();
108
  final ui.Image replacementImage = await createTestImage();
109 110

  group('FadeInImage', () {
111
    testWidgets('animates an uncached image', (WidgetTester tester) async {
112 113
      final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
      final TestImageProvider imageProvider = TestImageProvider(targetImage);
114

115
      await tester.pumpWidget(FadeInImage(
116 117
        placeholder: placeholderProvider,
        image: imageProvider,
118 119 120 121 122
        fadeOutDuration: animationDuration,
        fadeInDuration: animationDuration,
        fadeOutCurve: Curves.linear,
        fadeInCurve: Curves.linear,
        excludeFromSemantics: true,
123 124
      ));

125
      expect(findFadeInImage(tester).placeholder!.rawImage.image, null);
126 127
      expect(findFadeInImage(tester).target.rawImage.image, null);

128 129
      placeholderProvider.complete();
      await tester.pump();
130
      expect(findFadeInImage(tester).placeholder!.rawImage.image!.isCloneOf(placeholderImage), true);
131
      expect(findFadeInImage(tester).target.rawImage.image, null);
132

133 134 135 136
      imageProvider.complete();
      await tester.pump();
      for (int i = 0; i < 5; i += 1) {
        final FadeInImageParts parts = findFadeInImage(tester);
137 138 139
        expect(parts.placeholder!.rawImage.image!.isCloneOf(placeholderImage), true);
        expect(parts.target.rawImage.image!.isCloneOf(targetImage), true);
        expect(parts.placeholder!.opacity, moreOrLessEquals(1 - i / 5));
140
        expect(parts.target.opacity, 0);
141 142
        await tester.pump(const Duration(milliseconds: 10));
      }
143 144 145

      for (int i = 0; i < 5; i += 1) {
        final FadeInImageParts parts = findFadeInImage(tester);
146 147 148
        expect(parts.placeholder!.rawImage.image!.isCloneOf(placeholderImage), true);
        expect(parts.target.rawImage.image!.isCloneOf(targetImage), true);
        expect(parts.placeholder!.opacity, 0);
149
        expect(parts.target.opacity, moreOrLessEquals(i / 5));
150 151 152
        await tester.pump(const Duration(milliseconds: 10));
      }

153
      await tester.pumpWidget(FadeInImage(
154 155 156
        placeholder: placeholderProvider,
        image: imageProvider,
      ));
157
      expect(findFadeInImage(tester).target.rawImage.image!.isCloneOf(targetImage), true);
158 159 160
      expect(findFadeInImage(tester).target.opacity, 1);
    });

161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236
    testWidgets("FadeInImage's image obeys gapless playback", (WidgetTester tester) async {
      final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
      final TestImageProvider imageProvider = TestImageProvider(targetImage);
      final TestImageProvider secondImageProvider = TestImageProvider(replacementImage);

      await tester.pumpWidget(FadeInImage(
        placeholder: placeholderProvider,
        image: imageProvider,
        fadeOutDuration: animationDuration,
        fadeInDuration: animationDuration,
      ));

      imageProvider.complete();
      placeholderProvider.complete();
      await tester.pump();
      await tester.pump(animationDuration * 2);
      // Calls setState after the animation, which removes the placeholder image.
      await tester.pump(const Duration(milliseconds: 100));

      await tester.pumpWidget(FadeInImage(
        placeholder: placeholderProvider,
        image: secondImageProvider,
      ));
      await tester.pump();

      FadeInImageParts parts = findFadeInImage(tester);
      // Continually shows previously loaded image,
      expect(parts.placeholder, isNull);
      expect(parts.target.rawImage.image!.isCloneOf(targetImage), isTrue);
      expect(parts.target.opacity, 1);

      // Until the new image provider provides the image.
      secondImageProvider.complete();
      await tester.pump();

      parts = findFadeInImage(tester);
      expect(parts.target.rawImage.image!.isCloneOf(replacementImage), isTrue);
      expect(parts.target.opacity, 1);
    });

    testWidgets("FadeInImage's placeholder obeys gapless playback", (WidgetTester tester) async {
      final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
      final TestImageProvider secondPlaceholderProvider = TestImageProvider(replacementImage);
      final TestImageProvider imageProvider = TestImageProvider(targetImage);

      await tester.pumpWidget(FadeInImage(
        placeholder: placeholderProvider,
        image: imageProvider,
      ));

      placeholderProvider.complete();
      await tester.pump();

      FadeInImageParts parts = findFadeInImage(tester);
      expect(parts.placeholder!.rawImage.image!.isCloneOf(placeholderImage), true);
      expect(parts.placeholder!.opacity, 1);

      await tester.pumpWidget(FadeInImage(
        placeholder: secondPlaceholderProvider,
        image: imageProvider,
      ));

      parts = findFadeInImage(tester);
      // continually shows previously loaded image.
      expect(parts.placeholder!.rawImage.image!.isCloneOf(placeholderImage), true);
      expect(parts.placeholder!.opacity, 1);

      // Until the new image provider provides the image.
      secondPlaceholderProvider.complete();
      await tester.pump();

      parts = findFadeInImage(tester);
      expect(parts.placeholder!.rawImage.image!.isCloneOf(replacementImage), true);
      expect(parts.placeholder!.opacity, 1);
    });

237 238 239
    testWidgets('shows a cached image immediately when skipFadeOnSynchronousLoad=true', (WidgetTester tester) async {
      final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
      final TestImageProvider imageProvider = TestImageProvider(targetImage);
240
      imageProvider.resolve(ImageConfiguration.empty);
241 242
      imageProvider.complete();

243
      await tester.pumpWidget(FadeInImage(
244 245 246
        placeholder: placeholderProvider,
        image: imageProvider,
      ));
247

248
      expect(findFadeInImage(tester).target.rawImage.image!.isCloneOf(targetImage), true);
249 250 251
      expect(findFadeInImage(tester).placeholder, isNull);
      expect(findFadeInImage(tester).target.opacity, 1);
    });
252

253
    testWidgets('handles updating the placeholder image', (WidgetTester tester) async {
254
      final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
255
      final TestImageProvider secondPlaceholderProvider = TestImageProvider(replacementImage);
256
      final TestImageProvider imageProvider = TestImageProvider(targetImage);
257

258
      await tester.pumpWidget(FadeInImage(
259 260
        placeholder: placeholderProvider,
        image: imageProvider,
261 262 263
        fadeOutDuration: animationDuration,
        fadeInDuration: animationDuration,
        excludeFromSemantics: true,
264
      ));
265

266
      final State? state = findFadeInImage(tester).state;
267 268
      placeholderProvider.complete();
      await tester.pump();
269
      expect(findFadeInImage(tester).placeholder!.rawImage.image!.isCloneOf(placeholderImage), true);
270

271
      await tester.pumpWidget(FadeInImage(
272 273
        placeholder: secondPlaceholderProvider,
        image: imageProvider,
274 275 276
        fadeOutDuration: animationDuration,
        fadeInDuration: animationDuration,
        excludeFromSemantics: true,
277
      ));
278

279 280
      secondPlaceholderProvider.complete();
      await tester.pump();
281
      expect(findFadeInImage(tester).placeholder!.rawImage.image!.isCloneOf(replacementImage), true);
282 283 284
      expect(findFadeInImage(tester).state, same(state));
    });

285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306
    testWidgets('does not keep the placeholder in the tree if it is invisible', (WidgetTester tester) async {
      final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
      final TestImageProvider imageProvider = TestImageProvider(targetImage);

      await tester.pumpWidget(FadeInImage(
        placeholder: placeholderProvider,
        image: imageProvider,
        fadeOutDuration: animationDuration,
        fadeInDuration: animationDuration,
        excludeFromSemantics: true,
      ));

      placeholderProvider.complete();
      await tester.pumpAndSettle();

      expect(find.byType(Image), findsNWidgets(2));

      imageProvider.complete();
      await tester.pumpAndSettle();
      expect(find.byType(Image), findsOneWidget);
    });

307
    testWidgets("doesn't interrupt in-progress animation when animation values are updated", (WidgetTester tester) async {
308 309
      final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
      final TestImageProvider imageProvider = TestImageProvider(targetImage);
310

311 312 313 314 315 316 317 318
      await tester.pumpWidget(FadeInImage(
        placeholder: placeholderProvider,
        image: imageProvider,
        fadeOutDuration: animationDuration,
        fadeInDuration: animationDuration,
        excludeFromSemantics: true,
      ));

319
      final State? state = findFadeInImage(tester).state;
320 321 322 323
      placeholderProvider.complete();
      imageProvider.complete();
      await tester.pump();
      await tester.pump(animationDuration);
324

325 326 327 328 329 330 331 332 333
      await tester.pumpWidget(FadeInImage(
        placeholder: placeholderProvider,
        image: imageProvider,
        fadeOutDuration: animationDuration * 2,
        fadeInDuration: animationDuration * 2,
        excludeFromSemantics: true,
      ));

      expect(findFadeInImage(tester).state, same(state));
334
      expect(findFadeInImage(tester).placeholder!.opacity, moreOrLessEquals(0));
335 336
      expect(findFadeInImage(tester).target.opacity, moreOrLessEquals(0));
      await tester.pump(animationDuration);
337
      expect(findFadeInImage(tester).placeholder!.opacity, moreOrLessEquals(0));
338 339 340
      expect(findFadeInImage(tester).target.opacity, moreOrLessEquals(1));
    });

341
    group('ImageProvider', () {
342

343
      test('memory placeholder cacheWidth and cacheHeight is passed through', () async {
344 345 346 347 348 349 350 351 352 353 354
        final Uint8List testBytes = Uint8List.fromList(kTransparentImage);
        final FadeInImage image = FadeInImage.memoryNetwork(
          placeholder: testBytes,
          image: 'test.com',
          placeholderCacheWidth: 20,
          placeholderCacheHeight: 30,
          imageCacheWidth: 40,
          imageCacheHeight: 50,
        );

        bool called = false;
355
        Future<ui.Codec> decode(ui.ImmutableBuffer buffer, {int? cacheWidth, int? cacheHeight, bool allowUpscaling = false}) {
356 357
          expect(cacheWidth, 20);
          expect(cacheHeight, 30);
358
          expect(allowUpscaling, false);
359
          called = true;
360
          return PaintingBinding.instance.instantiateImageCodecFromBuffer(buffer, cacheWidth: cacheWidth, cacheHeight: cacheHeight, allowUpscaling: allowUpscaling);
361
        }
362 363 364 365
        final ImageProvider resizeImage = image.placeholder;
        expect(image.placeholder, isA<ResizeImage>());
        expect(called, false);
        final LoadTestImageProvider testProvider = LoadTestImageProvider(image.placeholder);
366 367 368 369 370 371 372 373
        final ImageStreamCompleter streamCompleter = testProvider.testLoad(await resizeImage.obtainKey(ImageConfiguration.empty), decode);

        final Completer<void> completer = Completer<void>();
        streamCompleter.addListener(ImageStreamListener((ImageInfo imageInfo, bool syncCall) {
          completer.complete();
        }));
        await completer.future;

374 375 376
        expect(called, true);
      });

377
      test('do not resize when null cache dimensions', () async {
378 379 380 381 382 383 384
        final Uint8List testBytes = Uint8List.fromList(kTransparentImage);
        final FadeInImage image = FadeInImage.memoryNetwork(
          placeholder: testBytes,
          image: 'test.com',
        );

        bool called = false;
385
        Future<ui.Codec> decode(ui.ImmutableBuffer buffer, {int? cacheWidth, int? cacheHeight, bool allowUpscaling = false}) {
386 387
          expect(cacheWidth, null);
          expect(cacheHeight, null);
388
          expect(allowUpscaling, false);
389
          called = true;
390
          return PaintingBinding.instance.instantiateImageCodecFromBuffer(buffer, cacheWidth: cacheWidth, cacheHeight: cacheHeight);
391
        }
392 393 394 395 396
        // image.placeholder should be an instance of MemoryImage instead of ResizeImage
        final ImageProvider memoryImage = image.placeholder;
        expect(image.placeholder, isA<MemoryImage>());
        expect(called, false);
        final LoadTestImageProvider testProvider = LoadTestImageProvider(image.placeholder);
397 398 399 400 401 402 403 404
        final ImageStreamCompleter streamCompleter = testProvider.testLoad(await memoryImage.obtainKey(ImageConfiguration.empty), decode);

        final Completer<void> completer = Completer<void>();
        streamCompleter.addListener(ImageStreamListener((ImageInfo imageInfo, bool syncCall) {
          completer.complete();
        }));
        await completer.future;

405 406 407 408
        expect(called, true);
      });
    });

409 410
    group('semantics', () {
      testWidgets('only one Semantics node appears within FadeInImage', (WidgetTester tester) async {
411 412
        final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
        final TestImageProvider imageProvider = TestImageProvider(targetImage);
413

414
        await tester.pumpWidget(FadeInImage(
415 416
          placeholder: placeholderProvider,
          image: imageProvider,
417 418
        ));

419
        expect(find.byType(Semantics), findsOneWidget);
420 421
      });

422
      testWidgets('is excluded if excludeFromSemantics is true', (WidgetTester tester) async {
423 424
        final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
        final TestImageProvider imageProvider = TestImageProvider(targetImage);
425

426
        await tester.pumpWidget(FadeInImage(
427 428 429
          placeholder: placeholderProvider,
          image: imageProvider,
          excludeFromSemantics: true,
430 431
        ));

432
        expect(find.byType(Semantics), findsNothing);
433 434
      });

435 436 437 438 439 440 441 442 443
      group('label', () {
        const String imageSemanticText = 'Test image semantic label';

        testWidgets('defaults to image label if placeholder label is unspecified', (WidgetTester tester) async {
          Semantics semanticsWidget() => tester.widget(find.byType(Semantics));

          final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
          final TestImageProvider imageProvider = TestImageProvider(targetImage);

444 445 446 447 448 449 450 451 452
          await tester.pumpWidget(Directionality(
            textDirection: TextDirection.ltr,
            child: FadeInImage(
              placeholder: placeholderProvider,
              image: imageProvider,
              fadeOutDuration: animationDuration,
              fadeInDuration: animationDuration,
              imageSemanticLabel: imageSemanticText,
            ),
453
          ));
454

455 456 457
          placeholderProvider.complete();
          await tester.pump();
          expect(semanticsWidget().properties.label, imageSemanticText);
458

459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486
          imageProvider.complete();
          await tester.pump();
          await tester.pump(const Duration(milliseconds: 51));
          expect(semanticsWidget().properties.label, imageSemanticText);
        });

        testWidgets('is empty without any specified semantics labels', (WidgetTester tester) async {
          Semantics semanticsWidget() => tester.widget(find.byType(Semantics));

          final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
          final TestImageProvider imageProvider = TestImageProvider(targetImage);

          await tester.pumpWidget(FadeInImage(
              placeholder: placeholderProvider,
              image: imageProvider,
              fadeOutDuration: animationDuration,
              fadeInDuration: animationDuration,
          ));

          placeholderProvider.complete();
          await tester.pump();
          expect(semanticsWidget().properties.label, isEmpty);

          imageProvider.complete();
          await tester.pump();
          await tester.pump(const Duration(milliseconds: 51));
          expect(semanticsWidget().properties.label, isEmpty);
        });
487 488
      });
    });
489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519

    group("placeholder's BoxFit", () {
      testWidgets("should be the image's BoxFit when not set", (WidgetTester tester) async {
        final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
        final TestImageProvider imageProvider = TestImageProvider(targetImage);

        await tester.pumpWidget(FadeInImage(
          placeholder: placeholderProvider,
          image: imageProvider,
          fit: BoxFit.cover,
        ));

        expect(findFadeInImage(tester).placeholder!.fit, equals(findFadeInImage(tester).target.fit));
        expect(findFadeInImage(tester).placeholder!.fit, equals(BoxFit.cover));
      });

      testWidgets('should be the given value when set', (WidgetTester tester) async {
        final TestImageProvider placeholderProvider = TestImageProvider(placeholderImage);
        final TestImageProvider imageProvider = TestImageProvider(targetImage);

        await tester.pumpWidget(FadeInImage(
          placeholder: placeholderProvider,
          image: imageProvider,
          fit: BoxFit.cover,
          placeholderFit: BoxFit.fill,
        ));

        expect(findFadeInImage(tester).target.fit, equals(BoxFit.cover));
        expect(findFadeInImage(tester).placeholder!.fit, equals(BoxFit.fill));
      });
    });
520 521
  });
}