import'package:build/build.dart';/// The builder factory used by the `build.yaml` script.BuildersimpleBuilder(BuilderOptionsoptions)=>SimpleBuilder();/// A trivial builder which copies the contents of a `spec` file into a `dart` file.classSimpleBuilderextendsBuilder{@overrideMap<String,List<String>>getbuildExtensions=>const<String,List<String>>{'.spec':<String>['.dart']};@overrideFuture<void>build(BuildStepbuildStep)async{finalAssetIdoutput=buildStep.inputId.changeExtension('.dart');finalStringcontents=awaitbuildStep.readAsString(buildStep.inputId);buildStep.writeAsString(output,contents);}}