'package:extended_text/src/extended/text_overflow_mixin.dart': Failed assertion: line 1309 pos 45: 'start <= end': is not true

[JDongKhan]

Version

15.0.2

Platforms

dart

Device Model

iPhone 15模拟器

flutter info

[✓] Flutter (Channel stable, 3.41.8, on macOS 26.4.1 25E253 darwin-arm64, locale zh-Hans-CN) [787ms]
    • Flutter version 3.41.8 on channel stable at /Users/jd/fvm/versions/3.41.8
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    • Dart version 3.11.5
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[✓] Android toolchain - develop for Android devices (Android SDK version 36.0.0) [4.4s]
    • Android SDK at /Users/jd/Documents/sdk/android-sdk-macosx
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    • Platform android-36, build-tools 36.0.0
    • ANDROID_HOME = /Users/jd/Documents/sdk/android-sdk-macosx
    • Java binary at: /Applications/Android Studio.app/Contents/jbr/Contents/Home/bin/java
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[✓] Chrome - develop for the web [5ms]
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Connected device (5 available) [8.6s]
    • 公司的iPhone 12 mini (wireless) (mobile) • 00008101-000E20DC0C28001E            • ios            • iOS 17.3.1 21D61
    • 王金东的iPhone (wireless) (mobile)        • 00008101-001E518E21FA001E            • ios            • iOS 26.5.2 23F84
    • iPhone 15 (mobile)                    • CDB690EF-693F-49F0-BB7A-B3E899D14D08 • ios            • com.apple.CoreSimulator.SimRuntime.iOS-17-5 (simulator)
    • macOS (desktop)                       • macos                                • darwin-arm64   • macOS 26.4.1 25E253 darwin-arm64
    • Chrome (web)                          • chrome                               • web-javascript • Google Chrome 148.0.7778.168
    ! Error: Browsing on the local area network for iPhone 12. Ensure the device is unlocked and attached with a cable or associated with the same local area network as this Mac.
      The device must be opted into Developer Mode to connect wirelessly. (code -27)
    ! Error: Browsing on the local area network for 顾杰的iPhone. Ensure the device is unlocked and attached with a cable or associated with the same local area network as this Mac.
      The device must be opted into Developer Mode to connect wirelessly. (code -27)
    ! Error: Browsing on the local area network for iPhone (7). Ensure the device is unlocked and attached with a cable or associated with the same local area network as this Mac.
      The device must be opted into Developer Mode to connect wirelessly. (code -27)

[✓] Network resources [565ms]
    • All expected network resources are available.

• No issues found!
Process finished with exit code 0

How to reproduce?

ExtendedText放到列表中，进入后不会报错，多次滑动就报错了

Logs

flutter: 'package:extended_text/src/extended/text_overflow_mixin.dart': Failed assertion: line 1309 pos 45: 'start <= end': is not true.
flutter: 
#0      _AssertionError._doThrowNew (dart:core-patch/errors_patch.dart:67:4)
#1      _AssertionError._throwNew (dart:core-patch/errors_patch.dart:49:5)
#2      new _TextRange (package:extended_text/src/extended/text_overflow_mixin.dart:1309:45)
#3      _TextRange.copyWith (package:extended_text/src/extended/text_overflow_mixin.dart:1319:50)
#4      TextOverflowMixin._findNoOverflow (package:extended_text/src/extended/text_overflow_mixin.dart:491:38)
#5      TextOverflowMixin.layoutOverflow (package:extended_text/src/extended/text_overflow_mixin.dart:126:29)
#6      ExtendedRenderParagraph.performLayout (package:extended_text/src/extended/rendering/paragraph.dart:175:5)
#7      RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#8      ChildLayoutHelper.layoutChild (package:flutter/src/rendering/layout_helper.dart:62:11)
#9      RenderFlex._computeSizes (package:flutter/src/rendering/flex.dart:1275:26)
#10     RenderFlex.performLayout (package:flutter/src/rendering/flex.d<…>
flutter: ----------------------------------------------------

======== Exception caught by Flutter framework =====================================================
The following assertion was thrown:
'package:extended_text/src/extended/text_overflow_mixin.dart': Failed assertion: line 1309 pos 45: 'start <= end': is not true.

When the exception was thrown, this was the stack: 
#2      new _TextRange (package:extended_text/src/extended/text_overflow_mixin.dart:1309:45)
#3      _TextRange.copyWith (package:extended_text/src/extended/text_overflow_mixin.dart:1319:50)
#4      TextOverflowMixin._findNoOverflow (package:extended_text/src/extended/text_overflow_mixin.dart:491:38)
#5      TextOverflowMixin.layoutOverflow (package:extended_text/src/extended/text_overflow_mixin.dart:126:29)
#6      ExtendedRenderParagraph.performLayout (package:extended_text/src/extended/rendering/paragraph.dart:175:5)
#7      RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#8      ChildLayoutHelper.layoutChild (package:flutter/src/rendering/layout_helper.dart:62:11)
#9      RenderFlex._computeSizes (package:flutter/src/rendering/flex.dart:1275:26)
#10     RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:1329:32)
#11     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#12     ChildLayoutHelper.layoutChild (package:flutter/src/rendering/layout_helper.dart:62:11)
#13     RenderFlex._computeSizes (package:flutter/src/rendering/flex.dart:1275:26)
#14     RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:1329:32)
#15     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#16     ChildLayoutHelper.layoutChild (package:flutter/src/rendering/layout_helper.dart:62:11)
#17     RenderFlex._computeSizes (package:flutter/src/rendering/flex.dart:1237:28)
#18     RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:1329:32)
#19     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#20     RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:262:12)
#21     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#22     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:118:18)
#23     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#24     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:118:18)
#25     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#26     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:118:18)
#27     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#28     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:118:18)
#29     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#30     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:118:18)
#31     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#32     RenderSliverMultiBoxAdaptor.insertAndLayoutChild (package:flutter/src/rendering/sliver_multi_box_adaptor.dart:520:13)
#33     RenderSliverList.performLayout.advance (package:flutter/src/rendering/sliver_list.dart:238:19)
#34     RenderSliverList.performLayout (package:flutter/src/rendering/sliver_list.dart:278:12)
#35     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#36     RenderSliverEdgeInsetsPadding.performLayout (package:flutter/src/rendering/sliver_padding.dart:133:12)
#37     RenderSliverPadding.performLayout (package:flutter/src/rendering/sliver_padding.dart:368:11)
#38     RenderObject.layout (package:flutter/src/rendering/object.dart:2768:7)
#39     RenderViewportBase.layoutChildSequence (package:flutter/src/rendering/viewport.dart:673:13)
#40     RenderViewport._attemptLayout (package:flutter/src/rendering/viewport.dart:1684:12)
#41     RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:1575:20)
#42     RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:2616:7)
#43     PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:1174:18)
#44     PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:1187:15)
#45     RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:629:23)
#46     WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:1304:13)
#47     RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:495:5)
#48     SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1430:15)
#49     SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1345:9)
#50     SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:1198:5)
#54     _invoke (dart:ui/hooks.dart:358:10)
#55     PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:444:5)
#56     _drawFrame (dart:ui/hooks.dart:328:31)
(elided 5 frames from class _AssertionError and dart:async)
====================================================================================================

Example code (optional)

ExtendedText(
      text,
      style: const TextStyle(fontWeight: FontWeight.bold),
      maxLines: 1,
      overflowWidget: const TextOverflowWidget(
        position: TextOverflowPosition.start,
        child: Text('...'),
      ),
    )

Contact

No response

[ggvle]

For the same issue, AI says the reason is a bug in the TextOverflowPosition.middle algorithm in extended_text 15.0.2: it calculates the character range on either side of the ellipsis by subtracting the width already used by each line from the total line width, and when this available width gets very small (even smaller than the ellipsis itself), the calculated start ends up greater than end, which triggers an assert(start <= end) in the _TextRange constructor and throws an exception.