anchor.diff:    }
   }
   
  -class MockFuchsiaKernelCompiler extends Mock implements FuchsiaKernelCompiler {
  +class FakeFuchsiaKernelCompiler extends Fake implements FuchsiaKernelCompiler {
     @override
     Future<void> build({
       @required FuchsiaProject fuchsiaProject,
  
positive.code:   }
  }
  
  class MockFuchsiaSdk extends Mock implements FuchsiaSdk {
    @override
    final FuchsiaPM fuchsiaPM = MockFuchsiaPM();
  
    @override
    final FuchsiaKernelCompiler fuchsiaKernelCompiler =
        MockFuchsiaKernelCompiler();
  }
  
negative.code: import 'package:flutter_tools/src/fuchsia/fuchsia_sdk.dart';
  import 'package:flutter_tools/src/project.dart';
  import 'package:meta/meta.dart';
  import 'package:process/process.dart';
  import 'package:test/fake.dart';
  
  import '../../src/common.dart';
  import '../../src/context.dart';
  import '../../src/testbed.dart';
  
  // Defined globally for fakes to use.
  FileSystem fileSystem;
  
  void main() {
  