ember-memory-leaks-codemod/transforms/prototype-reference-leaks/index.js

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const { getParser } = require('codemod-cli').jscodeshift;
const { getOptions } = require('codemod-cli');

module.exports = function transformer(file, api) {
  const j = getParser(api);
  const options = getOptions();
  const root = j(file.source);

  const ignoreProps = [
    'classNames', 
    'classNameBindings',
    'attributeBindings',
    'queryParams'
  ];

  const createInit = (props, exp) => {
    // First create the super call for init
    let superCall = j.expressionStatement(
      j.callExpression(
        j.memberExpression(
          j.thisExpression(),
          j.identifier('_super'),
          false
        ),[j.identifier('...arguments')]));

    let initProp = j.objectMethod(
      "method",
      j.identifier('init'), 
      [],
      j.blockStatement([superCall, exp]));

    props.push(initProp);

  };

  const createThisExp = (name, value) => {
    return j.expressionStatement(
      j.assignmentExpression(
        '=',
        j.memberExpression(
          j.thisExpression(),
          j.identifier(name), 
          false)
        ,value));
  };

  root.find(j.ExportDefaultDeclaration).forEach(path => {
    let dec = path.value.declaration;
    let props = dec.arguments[0].properties;

    let initFn = props.filter(p => { 
      return p.key.name === "init"
    })[0];


    let arrExps = props.filter(p => {
      return p.value ? p.value.type === "ArrayExpression" : p.type === "ArrayExpression";
    });

    let objExps = props.filter(p => {
      return p.value ? p.value.type === "CallExpression" && p.value.callee.object.name === "Object"
        : p.type === "CallExpression" && p.callee.object.name === "Object";
    })

    // Adding new assignment expressions for each array expression
    arrExps.forEach(a => {

      let thisExp = createThisExp(a.key.name, a.value);
      let initFnBody;

      if(initFn) {
        initFnBody =  initFn.body.body;
        initFnBody.push(thisExp);
      } else {
        // We don't have an init() , hence create one
        createInit(props, thisExp);

      }

      // Removing array expression values from properties
      props.splice(props.findIndex(p => {
        let _type = p.value ? p.value.type : p.type;
        return _type === "ArrayExpression" && !ignoreProps.includes(p.key.name);
      }),1);

    });

    // Adding new assignment expressions for each object expression
    objExps.forEach(o => {

      let thisExp = createThisExp(o.key.name, o.value);
      let initFnBody;

      if(initFn) {
        initFnBody =  initFn.body.body;
        initFnBody.push(thisExp);
      } else {
        // We don't have an init() , hence create one
        createInit(props, thisExp);
      }

      // Removing object expression values from properties
      props.splice(props.findIndex(p => p.value.type === "CallExpression" && p.value.callee.object.name === "Object"),1);

    });

  });

  return root.toSource();
}