anchor.diff:      String context = 'in $member:\n'
           'Expected: $expectedImpact\nActual: $typeUses';
       for (TypeUse typeUse in typeUses) {
  -      String type = '${typeUse.type}';
  +      String type = printType(typeUse.type);
         switch (typeUse.kind) {
           case TypeUseKind.AS_CAST:
             Expect.isTrue(asCasts.contains(type), "Extra $typeUse $context");
  
positive.code: }
  ''';
  
    Map<String, Impact> expectedImpactMap = <String, Impact>{
      'method1': const Impact(),
      'method2': new Impact(implicitCasts: ['int']),
      'method3': new Impact(parameterChecks: ['int']),
  
negative.code:     'method13': new Impact(implicitCasts: ['int'], parameterChecks: ['String']),
    };
  
    Map<String, Impact> expectedImpactMapNnbdOn = <String, Impact>{
      'method1': const Impact(),
      'method2': new Impact(implicitCasts: ['int*']),
      'method3': new Impact(parameterChecks: ['int*']),
      'method4': new Impact(asCasts: ['int*']),
      'method5': const Impact(),
      'method6': const Impact(),
      'method7': const Impact(),
      'method8': const Impact(),
      'method9': new Impact(implicitCasts: ['int*']),
      'method10': const Impact(),
      'method11': const Impact(),
      'method12': const Impact(),
      'method13':
          new Impact(implicitCasts: ['int*'], parameterChecks: ['String*']),
    };
  
    Map<String, Impact> expectedImpactMap =
        isDart2jsNnbd ? expectedImpactMapNnbdOn : expectedImpactMapNnbdOff;
    retainDataForTesting = true;
    CompilationResult result =
        await runCompiler(memorySourceFiles: {'main.dart': source});
    Expect.isTrue(result.isSuccess);
    Compiler compiler = result.compiler;
    var options = compiler.options;
  
    String printType(DartType type) {
      return type.toStructuredText(
          printLegacyStars: true, useLegacySubtyping: options.useLegacySubtyping);
    }
  
    KClosedWorld closedWorld = compiler.frontendClosedWorldForTesting;
    ElementEnvironment elementEnvironment = closedWorld.elementEnvironment;
  