Codemod to migrate from Q to Bluebird

codemod.js

const replacements = {
  'thenResolve': 'thenReturn',
  'thenReject': 'thenThrow',
  'fcall': 'try'
}

export default function transformer(file, api) {
  const j = api.jscodeshift;
  const sourceCalls = [];
  const f = j(file.source);
  
  function replaceMethod(path) {
    const {callee, arguments: args} = path.node;
    const {object, property} = callee;
    const replacement = replacements[property.name];
    
    
    j(path).replaceWith(
      j.callExpression(j.memberExpression(
        object,
        j.identifier(replacement)
      ), args)
    )
  }
  
  function replaceQCall(path) {
    const {arguments: args} = path.node;
	j(path).replaceWith(
      j.callExpression(
        j.memberExpression(j.identifier('Promise'), j.identifier('resolve')),
        args
      )
    )
  }
  
  function replaceQ(path) {
    j(path).replaceWith(j.identifier('Promise'))
  }
  
  function isRequireQ(node) {
    return node.callee.name === 'require' &&
      node.arguments.length === 1 &&
      node.arguments[0].value === 'q';
  }
  
  function replaceRequire(path) {
    j(path).replaceWith(
      j.callExpression(
        path.node.callee,
        [j.literal('bluebird')]
      )
    )
  }
  
  f.find(j.CallExpression, node => {
    return node.callee.type === 'MemberExpression' &&
      replacements.hasOwnProperty(node.callee.property.name)
  })
  .forEach(replaceMethod);
  
  f.find(j.CallExpression, { callee: { name: 'q' }})
   .forEach(replaceQCall);
  
  f.find(j.Identifier, { name: 'q'} )
     .forEach(replaceQ);
  
  f.find(j.CallExpression, isRequireQ)
  	.forEach(replaceRequire)
  
  return f.toSource({quote: 'single'})
}