我在调试模式下运行应用程序，当我尝试热重启或热重启时，显示此错误，并且应用程序完成，这是在进行全面升级之后发生的。我不知道这个错误在哪里，我的应用程序在发布模式下正常工作
NoSuchMethodError: The method 'isAfter' was called on null.
Receiver: null
Tried calling: isAfter(Instance of 'DateTime')
#0 Object.noSuchMethod (dart:core/runtime/lib/object_patch.dart:50:5)
#1 _ManifestAssetBundle.needsBuild (package:flutter_tools/src/asset.dart:91:41)
#2 HotRunner._updateDevFS (package:flutter_tools/src/run_hot.dart:311:44)
<asynchronous suspension>
#3 HotRunner._reloadSources (package:flutter_tools/src/run_hot.dart:622:47)
<asynchronous suspension>
#4 HotRunner.restart (package:flutter_tools/src/run_hot.dart:566:24)
<asynchronous suspension>
#5 HotRunner.handleTerminalCommand (package:flutter_tools/src/run_hot.dart:281:24)
<asynchronous suspension>
#6 ResidentRunner.processTerminalInput (package:flutter_tools/src/resident_runner.dart:890:15)
<asynchronous suspension>
#7 _rootRunUnary (dart:async/zone.dart:1132:38)
#8 _CustomZone.runUnary (dart:async/zone.dart:1029:19)
#9 _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
#10 _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
#11 _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
#12 _SyncBroadcastStreamController._sendData (dart:async/broadcast_stream_controller.dart:375:20)
#13 _BroadcastStreamController.add (dart:async/broadcast_stream_controller.dart:250:5)
#14 _AsBroadcastStreamController.add (dart:async/broadcast_stream_controller.dart:474:11)
#15 _rootRunUnary (dart:async/zone.dart:1132:38)
#16 _CustomZone.runUnary (dart:async/zone.dart:1029:19)
#17 _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
#18 _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
#19 _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
#20 _SinkTransformerStreamSubscription._add (dart:async/stream_transformers.dart:68:11)
#21 _EventSinkWrapper.add (dart:async/stream_transformers.dart:15:11)
#22 _StringAdapterSink.add (dart:convert/string_conversion.dart:236:11)
#23 _StringAdapterSink.addSlice (dart:convert/string_conversion.dart:241:7)
#24 _Utf8ConversionSink.addSlice (dart:convert/string_conversion.dart:312:20)
#25 _ErrorHandlingAsciiDecoderSink.addSlice (dart:convert/ascii.dart:252:17)
#26 _ErrorHandlingAsciiDecoderSink.add (dart:convert/ascii.dart:238:5)
#27 _ConverterStreamEventSink.add (dart:convert/chunked_conversion.dart:72:18)
#28 _SinkTransformerStreamSubscription._handleData (dart:async/stream_transformers.dart:120:24)
#29 _rootRunUnary (dart:async/zone.dart:1132:38)
#30 _CustomZone.runUnary (dart:async/zone.dart:1029:19)
#31 _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
#32 _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
#33 _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
#34 _SyncStreamController._sendData (dart:async/stream_controller.dart:764:19)
#35 _StreamController._add (dart:async/stream_controller.dart:640:7)
#36 _StreamController.add (dart:async/stream_controller.dart:586:5)
#37 _Socket._onData (dart:io/runtime/bin/socket_patch.dart:1774:41)
#38 _rootRunUnary (dart:async/zone.dart:1136:13)
#39 _CustomZone.runUnary (dart:async/zone.dart:1029:19)
#40 _CustomZone.runUnaryGuarded (dart:async/zone.dart:931:7)
#41 _BufferingStreamSubscription._sendData (dart:async/stream_impl.dart:336:11)
#42 _BufferingStreamSubscription._add (dart:async/stream_impl.dart:263:7)
#43 _SyncStreamController._sendData (dart:async/stream_controller.dart:764:19)
#44 _StreamController._add (dart:async/stream_controller.dart:640:7)
#45 _StreamController.add (dart:async/stream_controller.dart:586:5)
#46 new _RawSocket.<anonymous closure> (dart:io/runtime/bin/socket_patch.dart:1323:33)
#47 _NativeSocket.issueReadEvent.issue (dart:io/runtime/bin/socket_patch.dart:844:14)
#48 _microtaskLoop (dart:async/schedule_microtask.dart:41:21)
#49 _startMicrotaskLoop (dart:async/schedule_microtask.dart:50:5)
#50 _runPendingImmediateCallback (dart:isolate/runtime/lib/isolate_patch.dart:115:13)
#51 _RawReceivePortImpl._handleMessage (dart:isolate/runtime/lib/isolate_patch.dart:172:5)