Compiler Error: Invalid argument(s): Type parameter T is not indexed

[marktanner1331]

Version information

Dart VM version: 2.7.0 (Fri Dec 6 16:26:51 2019 +0100) on "windows_x64"`

Code to replicate

Future main() async {
  MyClass sc = MyClass();
}

 class MyClass {
  final AwaitLock awaitLock = AwaitLock();

  Future<void> run() async {
    await awaitLock(() => Future<void>.sync(() => print("here")));
  }
}

class AwaitLock {
  Future<T> call<T>(Future<T> Function() f) async {
    return await f();
  }
}

Error

Invalid argument(s): Type parameter T is not indexed
#0      TypeParameterIndexer.[]  (package:kernel/binary/ast_to_binary.dart:2573:8)
#1      BinaryPrinter.visitTypeParameterType  (package:kernel/binary/ast_to_binary.dart:2125:38)
#2      TypeParameterType.accept  (package:kernel/ast.dart:5996:42)
#3      BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)

#4      LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)
#5      BinaryPrinter.writeNodeList  (package:kernel/binary/ast_to_binary.dart:302:7)
#6      BinaryPrinter.visitArguments  (package:kernel/binary/ast_to_binary.dart:1492:5)
#7      Arguments.accept  (package:kernel/ast.dart:3158:38)
#8      BinaryPrinter.writeArgumentsNode  (package:kernel/binary/ast_to_binary.dart:406:10)
#9      BinaryPrinter.visitStaticInvocation  (package:kernel/binary/ast_to_binary.dart:1476:5)
#10     StaticInvocation.accept  (package:kernel/ast.dart:3413:44)
#11     BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)

#12     LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)
#13     BinaryPrinter.visitExpressionStatement  (package:kernel/binary/ast_to_binary.dart:1791:5)
#14     ExpressionStatement.accept  (package:kernel/ast.dart:4491:43)
#15     BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)
#16     LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)
#17     BinaryPrinter.writeNodeList  (package:kernel/binary/ast_to_binary.dart:302:7)
#18     BinaryPrinter.visitBlock  (package:kernel/binary/ast_to_binary.dart:1799:5)

#19     Block.accept  (package:kernel/ast.dart:4519:43)
#20     BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)
#21     LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)
#22     BinaryPrinter.visitLabeledStatement  (package:kernel/binary/ast_to_binary.dart:1833:5)
#23     LabeledStatement.accept  (package:kernel/ast.dart:4633:43)
#24     BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)
#25     LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)

#26     BinaryPrinter.writeNodeList  (package:kernel/binary/ast_to_binary.dart:302:7)
#27     BinaryPrinter.visitBlock  (package:kernel/binary/ast_to_binary.dart:1799:5)
#28     Block.accept  (package:kernel/ast.dart:4519:43)
#29     BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)
#30     LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)
#31     BinaryPrinter.visitTryCatch  (package:kernel/binary/ast_to_binary.dart:1950:5)
#32     TryCatch.accept  (package:kernel/ast.dart:4984:43)
#33     BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)
#34     LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)

#35     BinaryPrinter.writeOptionalNode  (package:kernel/binary/ast_to_binary.dart:485:7)
#36     BinaryPrinter.visitFunctionNode  (package:kernel/binary/ast_to_binary.dart:1324:5)
#37     FunctionNode.accept  (package:kernel/ast.dart:2499:38)
#38     BinaryPrinter.writeFunctionNode  (package:kernel/binary/ast_to_binary.dart:399:10)
#39     BinaryPrinter.visitFunctionDeclaration  (package:kernel/binary/ast_to_binary.dart:2026:5)
#40     FunctionDeclaration.accept  (package:kernel/ast.dart:5328:43)
#41     BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)
#42     LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)
#43     BinaryPrinter.writeNodeList  (package:kernel/binary/ast_to_binary.dart:302:7)
#44     BinaryPrinter.visitBlock  (package:kernel/binary/ast_to_binary.dart:1799:5)
#45     Block.accept  (package:kernel/ast.dart:4519:43)
#46     BinaryPrinter.writeNode  (package:kernel/binary/ast_to_binary.dart:392:10)

#47     LimitedBinaryPrinter.writeNode  (package:kernel/binary/limited_ast_to_binary.dart:59:11)
#48     BinaryPrinter.writeOptionalNode  (package:kernel/binary/ast_to_binary.dart:485:7)
#49     BinaryPrinter.visitFunctionNode  (package:kernel/binary/ast_to_binary.dart:1324:5)
#50     FunctionNode.accept  (package:kernel/ast.dart:2499:38)
#51     BinaryPrinter.writeFunctionNode  (package:kernel/binary/ast_to_binary.dart:399:10)
#52     BinaryPrinter.writeOptionalFunctionNode  (package:kernel/binary/ast_to_binary.dart:494:7)
#53     BinaryPrinter.visitProcedure  (package:kernel/binary/ast_to_binary.dart:1200:5)
#54     Procedure.accept  (package:kernel/ast.dart:2140:40)
#55     BinaryPrinter.writeProcedureNode  (package:kernel/binary/ast_to_binary.dart:420:10)
#56     BinaryPrinter.writeProcedureNodeList  (package:kernel/binary/ast_to_binary.dart:311:7)
#57     BinaryPrinter.visitClass  (package:kernel/binary/ast_to_binary.dart:1128:5)
#58     Class.accept  (package:kernel/ast.dart:1218:38)
#59     BinaryPrinter.writeClassNode  (package:kernel/binary/ast_to_binary.dart:434:10)
#60     BinaryPrinter.writeClassNodeList  (package:kernel/binary/ast_to_binary.dart:329:7)
#61     BinaryPrinter.visitLibrary  (package:kernel/binary/ast_to_binary.dart:958:5)
#62     Library.accept  (package:kernel/ast.dart:532:38)
#63     BinaryPrinter.writeLibraryNode  (package:kernel/binary/ast_to_binary.dart:413:10)
#64     LimitedBinaryPrinter.writeLibraries  (package:kernel/binary/limited_ast_to_binary.dart:52:31)
#65     BinaryPrinter.writeComponentFile.<anonymous closure>  (package:kernel/binary/ast_to_binary.dart:562:7)
#66     Timeline.timeSync  (dart:developer/timeline.dart:163:22)
#67     BinaryPrinter.writeComponentFile  (package:kernel/binary/ast_to_binary.dart:546:14)
#68     serializeComponent  (package:front_end/src/fasta/kernel/utils.dart:75:11)
#69     _processLoadRequest  (file:///C:/b/s/w/ir/cache/builder/sdk/pkg/vm/bin/kernel_service.dart:724:41)
<asynchronous suspension>
#70     _RawReceivePortImpl._handleMessage  (dart:isolate-patch/isolate_patch.dart:174:12)

Remarks
This seems to be an issue with using the call method with generic arguments and await.

[mraleph]

Thank you for the report @marktanner1331

Does not reproduce on master, so I presume it is fixed.

/cc @jensjoha

[jensjoha]

A bisect shows it was fixed in a9485e8.