codemod: react 16 event prop warning if passes in boolean

react16_event_handler_undefined_or_function.js

/* eslint-disable */
const EVENT_NAMES = ['onMouseDown', 'onMouseUp', 'onClick', 'onKeyUp', 'onKeyDown']
// Press ctrl+space for code completion
export default function transformer(file, api) {
  const j = api.jscodeshift;
  let foundAttrs = j(file.source).find(j.JSXAttribute)

  var replacements = []

  foundAttrs = foundAttrs.forEach(path => {
    const k = j; // codeshift api
	var propsStartsWithOn = path.value.name.name.startsWith('on')


    const isAmpConditional = path.value.value && path.value.value.expression && path.value.value.expression.type === 'LogicalExpression' && path.value.value.expression.operator === '&&'
    if(path.value.name.name === 'onClick') { debugger }
    if (!(propsStartsWithOn && isAmpConditional)) return;


    var eventReplacer = `${j(path.value.value.expression.left).toSource()} ? ${j(path.value.value.expression.right).toSource()} : undefined`;
    var callbackReplacer = `${j(path.value.value.expression.left).toSource()} ? ${j(path.value.value.expression.right).toSource()} : _.noop`;
    var smartReplacer = eventReplacer
	replacements.push(
      [
        `${path.value.name.name}={${j(path.value.value.expression).toSource()}}`,
        `${path.value.name.name}={${smartReplacer}}`,
      ]
    )

	return true
  })

  var source = j(file.source)
    .find(j.Identifier)
    .toSource();
  source = replacements.reduce((source, rep) => source.replace(rep[0], rep[1]), source)
  debugger
  return source
}

/* eslint-enable */