anchor.diff:              expect(jsModules[0], contains('<<d2>>'));
               expect(jsModules[0], contains('<<e>>'));
   
  -            streamController.add('accept\n'.codeUnits);
  +            frontendServer.accept();
   
               fileE.writeAsStringSync("""
   import 'c.dart';
  
positive.code:           // The constant environment variable should be inlined as a boolean
            // literal.
            expect(resultFile.readAsStringSync(), contains('return true;'));
            outputParser.expectSources = false;
            count += 1;
            streamController.add('quit\n'.codeUnits);
          }
        });
        expect(await result, 0);
        expect(count, 2);
      });
  
      test('mixed compile expression commands with web target', () async {
  
negative.code:         '--incremental-serialization',
        ];
  
        final frontendServer = FrontendServer();
        Future<int> result = frontendServer.open(args);
        frontendServer.compile(file.path);
        int count = 0;
        frontendServer.listen((Result compiledResult) {
          CompilationResult result =
              CompilationResult.parse(compiledResult.status);
          switch (count) {
  