Tools like acorn[1] and Esprima[2] can parse the JavaScript source and output an ESTree compliant syntax tree. Then you can traverse it and modify it like any

Tools like acorn[1] and Esprima[2] can parse the JavaScript source and output an ESTree compliant syntax tree. Then you can traverse it and modify it like any other AST. [1] https://github.com/ternjs/acorn https://github.com/ternjs/acorn [2] http://esprima.org/ http://esprima.org/ [3] https://github.com/estree/estree https://github.com/estree/estree