|  | library; | 
|  | // | 
|  | // Problems in library: | 
|  | // | 
|  | // pkg/front_end/testcases/general/issue50382.dart:6:3: Error: The superclass, 'B', has no unnamed constructor that takes no arguments. | 
|  | //   A({required super.field}); | 
|  | //   ^ | 
|  | // | 
|  | // pkg/front_end/testcases/general/issue50382.dart:16:3: Error: The superclass, 'D', has no unnamed constructor that takes no arguments. | 
|  | //   C({required int super.field}); | 
|  | //   ^ | 
|  | // | 
|  | import self as self; | 
|  | import "dart:core" as core; | 
|  |  | 
|  | class A extends self::B { | 
|  | constructor •({required invalid-type field}) → self::A | 
|  | : final dynamic #t1 = invalid-expression "pkg/front_end/testcases/general/issue50382.dart:6:3: Error: The superclass, 'B', has no unnamed constructor that takes no arguments. | 
|  | A({required super.field}); | 
|  | ^" | 
|  | ; | 
|  | } | 
|  | class B extends core::Object { | 
|  | final field core::int field; | 
|  | constructor named({required core::int field}) → self::B | 
|  | : self::B::field = field, super core::Object::•() | 
|  | ; | 
|  | } | 
|  | class C extends self::D { | 
|  | constructor •({required core::int field}) → self::C | 
|  | : final dynamic #t2 = invalid-expression "pkg/front_end/testcases/general/issue50382.dart:16:3: Error: The superclass, 'D', has no unnamed constructor that takes no arguments. | 
|  | C({required int super.field}); | 
|  | ^" | 
|  | ; | 
|  | } | 
|  | class D extends core::Object { | 
|  | final field core::int field; | 
|  | constructor named({required core::int field}) → self::D | 
|  | : self::D::field = field, super core::Object::•() | 
|  | ; | 
|  | } |