parse(content, sourceName = '<compiler-parse-input>') {
    sourceName = this.normalize(sourceName);
    this.sourceMapCache_ = null;
    this.sourceMapConfiguration_ = null;

    let errorReporter = new CollectingErrorReporter();
    let sourceFile = new SourceFile(sourceName, content);
    let parser = new Parser(sourceFile, errorReporter, this.options_);
    let tree =
        this.options_.script ? parser.parseScript() : parser.parseModule();
    this.throwIfErrors(errorReporter);

    return tree;
  }
@param {string} content to be compiled.
@param {string} sourceName inserted into sourceMaps
@return {ParseTree}