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
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
// 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 separate from viewport_test.dart because we can't use both
// testWidgets and rendering_tester in the same file - testWidgets will
// initialize a binding, which rendering_tester will attempt to re-initialize
// (or vice versa).
import 'package:flutter/rendering.dart';
import 'package:flutter_test/flutter_test.dart';
import 'rendering_tester.dart';
void main() {
TestRenderingFlutterBinding.ensureInitialized();
const double width = 800;
const double height = 600;
Rect rectExpandedOnAxis(double value) => Rect.fromLTRB(0.0, 0.0 - value, width, height + value);
late List<RenderSliver> children;
setUp(() {
children = <RenderSliver>[
RenderSliverToBoxAdapter(
child: RenderSizedBox(const Size(800, 400)),
),
];
});
test('Cache extent - null, pixels', () async {
final RenderViewport renderViewport = RenderViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
children: children,
);
layout(renderViewport, phase: EnginePhase.flushSemantics);
expect(
renderViewport.describeSemanticsClip(null),
rectExpandedOnAxis(RenderAbstractViewport.defaultCacheExtent),
);
});
test('Cache extent - 0, pixels', () async {
final RenderViewport renderViewport = RenderViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
cacheExtent: 0.0,
children: children,
);
layout(renderViewport, phase: EnginePhase.flushSemantics);
expect(renderViewport.describeSemanticsClip(null), rectExpandedOnAxis(0.0));
});
test('Cache extent - 500, pixels', () async {
final RenderViewport renderViewport = RenderViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
cacheExtent: 500.0,
children: children,
);
layout(renderViewport, phase: EnginePhase.flushSemantics);
expect(renderViewport.describeSemanticsClip(null), rectExpandedOnAxis(500.0));
});
test('Cache extent - nullx viewport', () async {
await expectLater(
() => RenderViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
cacheExtentStyle: CacheExtentStyle.viewport,
children: children,
),
throwsAssertionError,
);
});
test('Cache extent - 0x viewport', () async {
final RenderViewport renderViewport = RenderViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
cacheExtent: 0.0,
cacheExtentStyle: CacheExtentStyle.viewport,
children: children,
);
layout(renderViewport);
expect(renderViewport.describeSemanticsClip(null), rectExpandedOnAxis(0));
});
test('Cache extent - .5x viewport', () async {
final RenderViewport renderViewport = RenderViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
cacheExtent: .5,
cacheExtentStyle: CacheExtentStyle.viewport,
children: children,
);
layout(renderViewport);
expect(renderViewport.describeSemanticsClip(null), rectExpandedOnAxis(height / 2));
});
test('Cache extent - 1x viewport', () async {
final RenderViewport renderViewport = RenderViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
cacheExtent: 1.0,
cacheExtentStyle: CacheExtentStyle.viewport,
children: children,
);
layout(renderViewport);
expect(renderViewport.describeSemanticsClip(null), rectExpandedOnAxis(height));
});
test('Cache extent - 2.5x viewport', () async {
final RenderViewport renderViewport = RenderViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
cacheExtent: 2.5,
cacheExtentStyle: CacheExtentStyle.viewport,
children: children,
);
layout(renderViewport);
expect(renderViewport.describeSemanticsClip(null), rectExpandedOnAxis(height * 2.5));
});
test('RenderShrinkWrappingViewport describeApproximatePaintClip with infinite viewportMainAxisExtent returns finite rect', () {
final RenderSliver child = CustomConstraintsRenderSliver(const SliverConstraints(
axisDirection: AxisDirection.down,
cacheOrigin: 0.0,
crossAxisDirection: AxisDirection.left,
crossAxisExtent: 400.0,
growthDirection: GrowthDirection.forward,
overlap: 1.0, // must not equal 0 for this test
precedingScrollExtent: 0.0,
remainingPaintExtent: double.infinity,
remainingCacheExtent: 0.0,
scrollOffset: 0.0,
userScrollDirection: ScrollDirection.idle,
viewportMainAxisExtent: double.infinity, // must == infinity
));
final RenderShrinkWrappingViewport viewport = RenderShrinkWrappingViewport(
crossAxisDirection: AxisDirection.left,
offset: ViewportOffset.zero(),
children: <RenderSliver>[ child ],
);
layout(viewport);
expect(
viewport.describeApproximatePaintClip(child),
const Rect.fromLTRB(0.0, 0.0, 800.0, 600.0),
);
});
}
class CustomConstraintsRenderSliver extends RenderSliver {
CustomConstraintsRenderSliver(this.constraints);
@override
SliverGeometry get geometry => SliverGeometry.zero;
@override
final SliverConstraints constraints;
@override
void performLayout() {}
}