jscodeshift

jscodeshift is a toolkit for running codemods over multiple JavaScript or TypeScript files. It provides A runner, which executes the provided transform for each file passed to it. It also outputs a summary of how many files have (not) been transformed. A wrapper around recast, providing a different API. Recast is an AST-to-AST transform tool and also tries to preserve the style of original code as much as possible. As already mentioned, jscodeshift also provides a wrapper around recast. In order to properly use the jscodeshift API, one has to understand the basic building blocks of recast (and ASTs) as well. An AST node is a plain JavaScript object with a specific set of fields, in accordance with the Mozilla Parser API. The primary way to identify nodes is via their type. It's OK to not know the structure of every AST node type. The (esprima) AST explorer is an online tool to inspect the AST for a given piece of JS code.