Spot

用于 Flutter widget 测试的链式查找器和更好的断言

用法

// Spotters
final homePage = spot.byType(MaterialApp).childByType(Scaffold);
final appBar = homePage.childByType(AppBar);

// Assertions
appBar.childByIcon(
  Icons.settings,
  parents: [spot.byType(IconButton)],
).existsOnce();

更好的错误信息

如果设置图标不存在，通常在使用 findsOneWidget 时会得到以下错误：

expect(find.byIcon(Icons.settings), findsOneWidget);

>>> Expected: exactly one matching node in the widget tree
>>>   Actual: _WidgetIconFinder:<zero widgets with icon "IconData(U+0E57F)" (ignoring offstage widgets)>
>>>    Which: means none were found but one was expected

上面的错误信息实际上没有太大帮助，因为实际的错误不是没有图标，而是使用了 Icons.home 而不是 Icons.settings。Spot 会打印一个大而有帮助的错误信息，其中包含显示的图标（IconData(U+0E318)）。

Could not find 'icon "IconData(U+0E57F)"' as child of #2 type "IconButton"
There are 1 possible parents for 'icon "IconData(U+0E57F)"' matching #2 type "IconButton". But non matched. The widget trees starting at #2 type "IconButton" are:
Possible parent 0:
IconButton(Icon, padding: EdgeInsets.all(8.0), dependencies: [_InheritedTheme, IconTheme, _LocalizationsScope-[GlobalKey#bdafc]])
└Semantics(container: false, properties: SemanticsProperties, renderObject: RenderSemanticsAnnotations#9b22d relayoutBoundary=up13)
 └InkResponse
  └_InkResponseStateWidget(gestures: [tap], mouseCursor: SystemMouseCursor(click), BoxShape.circle, dependencies: [MediaQuery], state: _InkResponseState#181bf)
   └_ParentInkResponseProvider
    └Actions(dispatcher: null, actions: {ActivateIntent: CallbackAction<ActivateIntent>#fded7, ButtonActivateIntent: CallbackAction<ButtonActivateIntent>#5d1ad}, state: _ActionsState#f4947)
     └_ActionsMarker
      └Focus(dependencies: [_FocusMarker], state: _FocusState#3db93)
       └_FocusMarker
        └Semantics(container: false, properties: SemanticsProperties, renderObject: RenderSemanticsAnnotations#d907f relayoutBoundary=up14)
         └MouseRegion(listeners: [enter, exit], cursor: SystemMouseCursor(click), renderObject: RenderMouseRegion#49c96 relayoutBoundary=up15)
          └Semantics(container: false, properties: SemanticsProperties, renderObject: RenderSemanticsAnnotations#e83d5 relayoutBoundary=up16)
           └GestureDetector(startBehavior: start, dependencies: [MediaQuery])
            └RawGestureDetector(state: RawGestureDetectorState#2d012(gestures: [tap], excludeFromSemantics: true, behavior: opaque))
             └Listener(listeners: [down], behavior: opaque, renderObject: RenderPointerListener#cab1c relayoutBoundary=up17)
              └ConstrainedBox(BoxConstraints(48.0<=w<=Infinity, 48.0<=h<=Infinity), renderObject: RenderConstrainedBox#96a26 relayoutBoundary=up18)
               └Padding(padding: EdgeInsets.all(8.0), dependencies: [Directionality], renderObject: RenderPadding#c223d relayoutBoundary=up19)
                └SizedBox(width: 24.0, height: 24.0, renderObject: RenderConstrainedBox#d47d4 relayoutBoundary=up20)
                 └Align(alignment: Alignment.center, dependencies: [Directionality], renderObject: RenderPositionedBox#ac4b6)
                  └Builder(dependencies: [IconTheme])
                   └IconTheme(color: Color(0xffffffff), size: 24.0)
                    └Icon(IconData(U+0E318), dependencies: [Directionality, IconTheme])
                     └Semantics(container: false, properties: SemanticsProperties, renderObject: RenderSemanticsAnnotations#ec9ab relayoutBoundary=up1)
                      └ExcludeSemantics(excluding: true, renderObject: RenderExcludeSemantics#5b179 relayoutBoundary=up2)
                       └SizedBox(width: 24.0, height: 24.0, renderObject: RenderConstrainedBox#eefd6 relayoutBoundary=up3)
                        └Center(alignment: Alignment.center, dependencies: [Directionality], renderObject: RenderPositionedBox#4c194)
                         └RichText(textDirection: ltr, softWrap: wrapping at box width, overflow: visible, maxLines: unlimited, text: "", dependencies: [_LocalizationsScope-[GlobalKey#bdafc]], renderObject: RenderParagraph#35451 relayoutBoundary=up1)
══╡ EXCEPTION CAUGHT BY FLUTTER TEST FRAMEWORK ╞════════════════════════════════════════════════════
The following TestFailure was thrown running a test:
Could not find 'icon "IconData(U+0E57F)"' as child of [type "MaterialApp" > 'type "Scaffold"' >
'type "AppBar"' && type "IconButton"]

目标

  • 创建可链式的小部件查找器，能够在断言失败时生成更好的错误信息
  • find.ancestor() 和 find.descendant() 速度较慢，spot 旨在通过遍历小部件树的子集来提高速度

项目状态

API 处于实验阶段，可能会发生变化。

许可证

Copyright 2022 Pascal Welsch

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   https://apache.ac.cn/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

GitHub

查看 Github