anchor.diff:    client.close();
     var builds = object["builds"] as List<dynamic>;
     if (builds == null || builds.isEmpty) {
  -    throw CommitNotBuiltException(
  +    throw NoResultsForCommitException(
           "Builder $builder hasn't built commit $commit");
     }
     var build = builds.last;
  
positive.code: }
  
  /// Exception thrown when looking up the build for a commit failed.
  class CommitNotBuiltException implements Exception {
    final String reason;
  
    CommitNotBuiltException(this.reason);
  
    String toString() => reason;
  }
  
negative.code:             "Warning: Searching for inexact baseline build: $e, continuing...");
        }
      }
      throw NoResultsForCommitException(
          "Failed to locate approximate baseline results for "
          "$commit in past $limit commits");
    }
  