CONTRIBUTING.md

pf-codemods

An eslint plugin (with an extra CLI utility) to help ease products transitioning to our new major @patternfly/react-core 4.0.0 release.

Goals

• We want to minimize code changes and respect existing code
• We only want to make safe modifications
  • Don't touch code that might not be PatternFly

redallen rationale

• Most consumers are using JSX, so we can write rules that target JSXElements
  • When they're using React.createElement or React.cloneElement that introduces unsafe complications

Design

• Use a JSX parser that leaves formatting alone as much as possible
• Add basic ESM import parsing to make sure we're only modifying PatternFly <Button>s

Development

This is what @redallen does to develop a rule:

1. Copy a similar rule from eslint-plugin-pf-codemods/lib/rules/*
2. Add it to the rules object at the top of eslint-plugin-pf-codemods/index.js
3. Copy a test at test/rules/* and write your test cases.

We now have a generator.

1. Run node generate new-rule-name to create the rule files
2. Run node test/rules/new-rule-name.js to test the rule

If you're having trouble writing a rule, you can:

1. Put code into an AST explorer like https://astexplorer.net/ to inspect all the AST nodes
2. console.dir(node, { depth: 5 }) to better inspect a node you're dealing with
3. Write rule targeting an AST node that has all the information you need. Confirm AST node exists in lib/rules/ast-node-types.d.ts.
4. Ask zallen on the RHUX or PatternFly Slack