Typescript transform test tool

transform-test.ts

function transformSourceFile(sourceText: string, transformers: ts.TransformerFactory<ts.SourceFile>[]) {
  const transformed = ts.transform(ts.createSourceFile('source.ts', sourceText, ts.ScriptTarget.ES2015), transformers);
  const printer = ts.createPrinter({ newLine: ts.NewLineKind.CarriageReturnLineFeed }, {
      onEmitNode: transformed.emitNodeWithNotification,
      substituteNode: transformed.substituteNode
  });
  const result = printer.printBundle(ts.createBundle(transformed.transformed));
  transformed.dispose();
  return result;
}