TypeError: Cannot read property 'start' of null in pure_component.js

[ritz078]

Here's the error:

TypeError: Cannot read property 'start' of null
    at reportSkipped (pure-component.js:86:28)
    at pure-component.js:97:9
    at Array.filter (native)
    at Collection.filter (/Users/ritz078/.npm-packages/lib/node_modules/jscodeshift/dist/Collection.js:60:46)
    at module.exports (pure-component.js:94:6)

[keyz]

Thanks for reporting this. Could you provide a sample code that causes this error?

[ritz078]

import React, { Component, PropTypes } from 'react';

import autoBind from '../utils/autoBind';

export default class Tag extends Component {
  constructor (props) {
    super(props);

    autoBind([
      'handleRemove'
    ], this);
  }

  handleRemove () {
    this.props.onRemove({
      id: this.props.id,
      text: this.props.text
    });
  }

  render () {
    const { showRemove, id, text } = this.props;
    return (
      <div className='ac-tag' data-id={id}>
        <span className='ac-tag-text'>{text}</span>
           {showRemove &&
             <span
               onClick={this.handleRemove}
               className='ac-tag-remove'
             >
                &#x2715;
             </span>
           }
      </div>
    );
  }
}

Tag.propTypes = {
  id: PropTypes.oneOfType([
    PropTypes.number, PropTypes.string
  ]),
  text: PropTypes.string.isRequired,
  onRemove: PropTypes.func,
  showRemove: PropTypes.bool
};

[DrewML]

Huh. So this was/is failing because the node being returned for this ClassDeclaration is missing the loc object (it's null). Reproducible here.

Could be fixed in this codemod itself by not reporting line/column information whenever it's missing (luckily this is only happening when the codemod tries to report that a Class was skipped), but this is probably an issue with the babel-core v5 parser that jscodeshift is using by default.

I tried stepping around the issue by specifying --parser babylon to jscodeshift, but ast-types then fails under the hood because Babylon diverges from the ESTree spec and uses the StringLiteral node type instead of the Literal type, which ast-types doesn't recognize yet (more discussion about this situation here).

@keyanzhang Interested in a PR just to prevent throwing an exception, or you want to leave as-is?

[keyz]

Thanks @DrewML! Sorry I've been traveling and just got back to the states. Could you try to switch to the Flow parser to see if it fixes the issue?

[ritz078]

any update on this ?

[surgeboris]

I've encountered same problem. Neither --parser babylon nor --parser flow does solve issue.
So I've created PR #78