anchor.diff:    }
   
     test_variable_getterInLib_setterInPart() async {
  -    addSource('/a.dart', '''
  +    addSource('$testPackageLibPath/a.dart', '''
   part of my.lib;
   void set x(int _) {}
   ''');
  
positive.code:     checkElementText(library, r'''
  library
    imports
      c.dart
    definingUnit
      topLevelVariables
        static v @19
  
negative.code:         supertype: NullSafeObject
          constructors
            synthetic @-1
              superConstructor: package:test/nullSafe.dart::@class::NullSafeObject::@constructor::•
          methods
            == @145
              parameters
  