flow-codemod

This repository contains a collection of codemod scripts for use with JSCodeshift that help update Flowified JS code.

Setup & Run

• npm install -g jscodeshift
• git clone https://github.com/flowtype/flow-codemod.git
• jscodeshift -t <codemod-script> <path> (but note that individual transforms may require additional options, as documented)
• Use the -d option for a dry-run and use -p to print the output for comparison

KNOWN ISSUES

• jscodeshift currently uses Babel 5, which fails to parse certain JS idioms. Files that fail to parse will not be transformed, unfortunately.

Included Scripts

The following codemods can be found under the transforms directory:

strict-type-args

Adds explicit arguments to polymorphic type application expressions, based on errors from Flow. For example,

let map: Map = ...

...becomes

let map: Map<any, any> = ...

This prepares code for an upcoming change to strict type argument processing. For instructions and more info, see documentation in the transform subdirectory.

License

flow-codemod is MIT licensed, as found in the LICENSE file.