anchor.diff:    return process2.exitCode;
   }
   
  -// Expects to be called with the path to the package root.
  -// See .test_config.
  -main(List<String> arguments) async {
  +/// Expects to be called with the path to the package root.
  +/// See .test_config.
  +void main(List<String> arguments) async {
     String packagePath = arguments[0];
     print("^^^ Run 'annotated_steps.dart' in $packagePath");
     int exitCode = await runBuildRunnerInDirectory(packagePath);
  
positive.code: 
  Uri baseUri = Platform.script.resolve("../../../../../");
  
  int runBuildRunnerInDirectory(String directory) async {
    print("^^^ Current working directory: ${Directory.current}");
    Map<String, String> environment =
        new Map<String, String>.from(Platform.environment);
    Directory.current = directory;
    print("^^^ Current working directory after change: ${Directory.current}");
  
    Process process1 =
        await Process.start('pub', ['get'], environment: environment);
    stdout.addStream(process1.stdout);
  
negative.code:   int exitCode = await process1.exitCode;
    if (exitCode != 0) return process1.exitCode;
  
    // Run `pub run build_runner test` and report exit code.
    Process process2 = await Process.start('pub', ['run', 'build_runner', 'test'],
        environment: environment);
    stdout.addStream(process2.stdout);
  