[Dart-Analysis] Internal error: type 'LibraryElementImpl' is not a subtype of type 'Fragment' in type cast

[NiclasLeichsenring]

The Dart Analysis Server crashes while I am analyzing my project since I updated to Flutter 3.29:

Dart SDK version: 3.7.0 (stable) (Wed Feb 5 04:53:58 2025 -0800) on "macos_arm64"

Dart analysis issue

Internal error: type 'LibraryElementImpl' is not a subtype of type 'Fragment' in type cast

Version information

• Dart SDK 3.7.0
• Dart IntelliJ 242.24931
• Android Studio Ladybug Feature Drop | 2024.2.2 Patch 1
• Mac OS X 15.3

Details

Internal error: type 'LibraryElementImpl' is not a subtype of type 'Fragment' in type cast
#0 LocalVariableElementImpl.enclosingFragment (package:analyzer/src/dart/element/element.dart:7487:55)
#1 _VariableBinder.joinPatternVariables (package:analyzer/src/dart/resolver/resolution_visitor.dart:1976:35)
#2 VariableBinder.logicalOrPatternFinish (package:_fe_analyzer_shared/src/type_inference/variable_bindings.dart:109:11)
#3 ResolutionVisitor.visitLogicalOrPattern (package:analyzer/src/dart/resolver/resolution_visitor.dart:1037:23)
#4 LogicalOrPatternImpl.accept (package:analyzer/src/dart/ast/ast.dart:11472:50)
#5 ResolutionVisitor.visitLogicalOrPattern (package:analyzer/src/dart/resolver/resolution_visitor.dart:1034:22)
#6 LogicalOrPatternImpl.accept (package:analyzer/src/dart/ast/ast.dart:11472:50)
#7 ResolutionVisitor._resolveGuardedPattern (package:analyzer/src/dart/resolver/resolution_visitor.dart:1615:28)
#8 ResolutionVisitor.visitSwitchExpression. (package:analyzer/src/dart/resolver/resolution_visitor.dart:1324:9)
#9 ResolutionVisitor._withNameScope (package:analyzer/src/dart/resolver/resolution_visitor.dart:1899:8)
#10 ResolutionVisitor.visitSwitchExpression (package:analyzer/src/dart/resolver/resolution_visitor.dart:1323:7)
#11 SwitchExpressionImpl.accept (package:analyzer/src/dart/ast/ast.dart:17115:50)
#12 AstResolver.resolveExpression (package:analyzer/src/summary2/ast_resolver.dart:107:10)
#13 _PropertyInducingElementTypeInference.perform (package:analyzer/src/summary2/top_level_inference.dart:265:17)
#14 PropertyInducingElementImpl.type (package:analyzer/src/dart/element/element.dart:10031:28)
#15 _InitializerInference.perform (package:analyzer/src/summary2/top_level_inference.dart:155:15)
#16 TopLevelInference.infer (package:analyzer/src/summary2/top_level_inference.dart:108:26)
#17 Linker._performTopLevelInference (package:analyzer/src/summary2/link.dart:426:29)
#18 Linker._buildOutlines (package:analyzer/src/summary2/link.dart:270:5)

#19 Linker.link. (package:analyzer/src/summary2/link.dart:125:7)

#20 OperationPerformanceImpl.runAsync (package:analyzer/src/util/performance/operation_performance.dart:174:14)

#21 Linker.link (package:analyzer/src/summary2/link.dart:124:5)

#22 link (package:analyzer/src/summary2/link.dart:43:3)

#23 LibraryContext.load.loadBundle. (package:analyzer/src/dart/analysis/library_context.dart:201:22)

#24 OperationPerformanceImpl.runAsync (package:analyzer/src/util/performance/operation_performance.dart:174:14)

#25 LibraryContext.load.loadBundle (package:analyzer/src/dart/analysis/library_context.dart:198:24)

#26 LibraryContext.load. (package:analyzer/src/dart/analysis/library_context.dart:286:7)

#27 PerformanceLog.runAsync (package:analyzer/src/dart/analysis/performance_logger.dart:50:14)

#28 LibraryContext.load (package:analyzer/src/dart/analysis/library_context.dart:277:5)

#29 AnalysisDriver._produceErrors (package:analyzer/src/dart/analysis/driver.dart:1933:5)

#30 AnalysisDriver.performWork (package:analyzer/src/dart/analysis/driver.dart:1265:7)

#31 AnalysisDriverScheduler._run (package:analyzer/src/dart/analysis/driver.dart:2438:7)

#0 LibraryContext._throwLibraryCycleLinkException (package:analyzer/src/dart/analysis/library_context.dart:415:5)
#1 LibraryContext.load.loadBundle (package:analyzer/src/dart/analysis/library_context.dart:212:11)

#2 LibraryContext.load. (package:analyzer/src/dart/analysis/library_context.dart:286:7)

#3 PerformanceLog.runAsync (package:analyzer/src/dart/analysis/performance_logger.dart:50:14)

#4 LibraryContext.load (package:analyzer/src/dart/analysis/library_context.dart:277:5)

#5 AnalysisDriver._produceErrors (package:analyzer/src/dart/analysis/driver.dart:1933:5)

#6 AnalysisDriver.performWork (package:analyzer/src/dart/analysis/driver.dart:1265:7)

#7 AnalysisDriverScheduler._run (package:analyzer/src/dart/analysis/driver.dart:2438:7)

[scheglov]

Do you have code that can reproduce this issue?

[scheglov]

Ah, looking closer into the stack trace, I saw nested LogicalOrPatterns.
It does not reproduce with two of them.
But does reproduce with three.

var x = switch (0) {
  var a || var a || var a => 0;
}

[scheglov]

https://dart-review.googlesource.com/c/sdk/+/410840

[NiclasLeichsenring]

Hi @scheglov @johnniwinther , this issue has not been fixed with Flutter 3.29.2 and Dart 3.7.2

Dart analysis issue

Internal error: type 'LibraryElementImpl' is not a subtype of type 'Fragment' in type cast

Version information

• Dart SDK 3.7.2
• Dart IntelliJ 243.23177
• Android Studio Meerkat | 2024.3.1
• Mac OS X 15.3

Details

Internal error: type 'LibraryElementImpl' is not a subtype of type 'Fragment' in type cast
#0 LocalVariableElementImpl.enclosingFragment (package:analyzer/src/dart/element/element.dart:7487:55)
#1 _VariableBinder.joinPatternVariables (package:analyzer/src/dart/resolver/resolution_visitor.dart:1976:35)
#2 VariableBinder.logicalOrPatternFinish (package:_fe_analyzer_shared/src/type_inference/variable_bindings.dart:109:11)
#3 ResolutionVisitor.visitLogicalOrPattern (package:analyzer/src/dart/resolver/resolution_visitor.dart:1037:23)
#4 LogicalOrPatternImpl.accept (package:analyzer/src/dart/ast/ast.dart:11472:50)
#5 ResolutionVisitor.visitLogicalOrPattern (package:analyzer/src/dart/resolver/resolution_visitor.dart:1034:22)
#6 LogicalOrPatternImpl.accept (package:analyzer/src/dart/ast/ast.dart:11472:50)
#7 ResolutionVisitor._resolveGuardedPattern (package:analyzer/src/dart/resolver/resolution_visitor.dart:1615:28)
#8 ResolutionVisitor.visitSwitchExpression. (package:analyzer/src/dart/resolver/resolution_visitor.dart:1324:9)
#9 ResolutionVisitor._withNameScope (package:analyzer/src/dart/resolver/resolution_visitor.dart:1899:8)
#10 ResolutionVisitor.visitSwitchExpression (package:analyzer/src/dart/resolver/resolution_visitor.dart:1323:7)
#11 SwitchExpressionImpl.accept (package:analyzer/src/dart/ast/ast.dart:17115:50)
#12 AstResolver.resolveExpression (package:analyzer/src/summary2/ast_resolver.dart:107:10)
#13 _PropertyInducingElementTypeInference.perform (package:analyzer/src/summary2/top_level_inference.dart:265:17)
#14 PropertyInducingElementImpl.type (package:analyzer/src/dart/element/element.dart:10031:28)
#15 _InitializerInference.perform (package:analyzer/src/summary2/top_level_inference.dart:155:15)
#16 TopLevelInference.infer (package:analyzer/src/summary2/top_level_inference.dart:108:26)
#17 Linker._performTopLevelInference (package:analyzer/src/summary2/link.dart:426:29)
#18 Linker._buildOutlines (package:analyzer/src/summary2/link.dart:270:5)

#19 Linker.link. (package:analyzer/src/summary2/link.dart:125:7)

#20 OperationPerformanceImpl.runAsync (package:analyzer/src/util/performance/operation_performance.dart:174:14)

#21 Linker.link (package:analyzer/src/summary2/link.dart:124:5)

#22 link (package:analyzer/src/summary2/link.dart:43:3)

#23 LibraryContext.load.loadBundle. (package:analyzer/src/dart/analysis/library_context.dart:201:22)

#24 OperationPerformanceImpl.runAsync (package:analyzer/src/util/performance/operation_performance.dart:174:14)

#25 LibraryContext.load.loadBundle (package:analyzer/src/dart/analysis/library_context.dart:198:24)

#26 LibraryContext.load.loadBundle (package:analyzer/src/dart/analysis/library_context.dart:148:9)

#27 LibraryContext.load. (package:analyzer/src/dart/analysis/library_context.dart:286:7)

#28 PerformanceLog.runAsync (package:analyzer/src/dart/analysis/performance_logger.dart:50:14)

#29 LibraryContext.load (package:analyzer/src/dart/analysis/library_context.dart:277:5)

#30 AnalysisDriver._produceErrors (package:analyzer/src/dart/analysis/driver.dart:1933:5)

#31 AnalysisDriver.performWork (package:analyzer/src/dart/analysis/driver.dart:1265:7)

#32 AnalysisDriverScheduler._run (package:analyzer/src/dart/analysis/driver.dart:2438:7)

#0      LibraryContext._throwLibraryCycleLinkException (package:analyzer/src/dart/analysis/library_context.dart:415:5)
#1      LibraryContext.load.loadBundle (package:analyzer/src/dart/analysis/library_context.dart:212:11)
<asynchronous suspension>
#2      LibraryContext.load.loadBundle (package:analyzer/src/dart/analysis/library_context.dart:148:9)
<asynchronous suspension>
#3      LibraryContext.load.<anonymous closure> (package:analyzer/src/dart/analysis/library_context.dart:286:7)
<asynchronous suspension>
#4      PerformanceLog.runAsync (package:analyzer/src/dart/analysis/performance_logger.dart:50:14)
<asynchronous suspension>
#5      LibraryContext.load (package:analyzer/src/dart/analysis/library_context.dart:277:5)
<asynchronous suspension>
#6      AnalysisDriver._produceErrors (package:analyzer/src/dart/analysis/driver.dart:1933:5)
<asynchronous suspension>
#7      AnalysisDriver.performWork (package:analyzer/src/dart/analysis/driver.dart:1265:7)
<asynchronous suspension>
#8      AnalysisDriverScheduler._run (package:analyzer/src/dart/analysis/driver.dart:2438:7)
<asynchronous suspension>

[johnniwinther]

The fix has landed but will unfortunately not be available before Dart 3.8. It is available in the dev builds and will be part of the first 3.8 beta release.

[NiclasLeichsenring]

The fix has landed but will unfortunately not be available before Dart 3.8. It is available in the dev builds and will be part of the first 3.8 beta release.

ok thank you for the info. I thought it will land in 3.7.2