React-docgen fails to parse components with optional chaining.

[mjhenkes]

If a component contains optional chaining it will now fail to parse. This used to work.

I'm on version 4.1.1.

Now you get this error:

Error: did not recognize object of type "ChainExpression"
    at Object.getFieldNames (/proj/node_modules/ast-types/lib/types.js:661:19)
    at visitChildren (/proj/node_modules/ast-types/lib/path-visitor.js:186:36)
    at Visitor.PVp.visitWithoutReset (/proj/node_modules/ast-types/lib/path-visitor.js:168:20)
    at visitChildren (/proj/node_modules/ast-types/lib/path-visitor.js:205:25)
    at Visitor.PVp.visitWithoutReset (/proj/node_modules/ast-types/lib/path-visitor.js:168:20)
    at NodePath.each (/proj/node_modules/ast-types/lib/path.js:89:26)
    at visitChildren (/proj/node_modules/ast-types/lib/path-visitor.js:180:18)
    at Visitor.PVp.visitWithoutReset (/proj/node_modules/ast-types/lib/path-visitor.js:168:20)
    at visitChildren (/proj/node_modules/ast-types/lib/path-visitor.js:205:25)
    at Visitor.PVp.visitWithoutReset (/proj/node_modules/ast-types/lib/path-visitor.js:168:20)

I kind of suspect this has to do with one of the transitive dependencies more that react-docgen but I'm logging this here first.

How to recreate, run the following test against the below jsx file.

test.js

const reactDocs = require('react-docgen');
const fs = require('fs');

const filePath = './file.jsx';

const source = fs.readFileSync(filePath, 'utf8');

const parsedProps = reactDocs.parse(source);

console.log('parsed', parsedProps);

file.jsx

import React from 'react';

const ApplicationBase = () => {
  const thing = {
    stuff: 'stuff',
  };

  // Parse works when the next line is commented out.
  const string = thing?.stuff;
  // Works when un-commented
  // const string = 'stuff';

  return (
    <div>
      {string}
    </div>
  );
};

export default ApplicationBase;

Also an issue template would help me remember all the things you'd like to see on an issue 😄

[mjhenkes]

I think this is likely related to @babel/parser@7.11.0 which released yesterday
https://www.npmjs.com/package/@babel/parser

[mjhenkes]

Here is a repo re-creating this issue: https://github.com/mjhenkes/react-doc-gen-test

[mjhenkes]

Looks like babel parser estree plugin made a change that is incompatible with ast-types
I've logged this issue babel/babel#11908 to babel to check if this considered a non passive change or if it's a bug that ast-types doesn't support the chainedExpression type.

[mjhenkes]

You can work around this problem by locking in your babel dependencies in your project's package.json

For example:

  "devDependencies": {
-    "@babel/core": "^7.5.0",
+    "@babel/core": "7.10.5",
+    "@babel/parser": "7.10.5",

Here's the change we made to our project:
https://github.com/cerner/terra-ui/pull/290/files

[mjhenkes]

Update: Babel says it's an intentional change. I've logged an issue to ast-types to add support for the chainExpression type.

[nafg]

@mjhenkes can you link the issue

[mjhenkes]

@nafg Sorry, I should have added that to my previous reply. benjamn/ast-types#383

[eps1lon]

On a different note: Should the AST even be handled by ast-types and not by @babel/types? Seems like babel is not tied to the AST spec that ast-types is using.

[jquense]

There isn't any need to use AST-types any more I don't think

[info-bit]

As I can see ast-types released a version to support the new ChainExpression. Should react-docgen update his internal dependency to close the issue?

[ethancrook99]

+1 for using the new version of ast-types

[brianespinosa]

@danez it appears that the above referenced PR resolves this issue with the new version of ast-types. I looked at the commit history and except for the above PR that resolves this, and a doc update, all of the commits since the last release seem to be Dependabot updates.

Based on this info, what are the chances we can get a patch or minor version release published since this particular issue is breaking a number of other projects, as seen from incoming references? Also, let me know if there is any way I can assist with this in case there is any work needed to evaluate the version bumps on dependencies to understand what our semantic version should be.

[lucantini]

Hi!

When can we expect a new release from react-docgen with these changes?

[jquense]

ping

[eps1lon]

Note that you can't fix this in your project without using e.g. resolutions in yarn. Package managers treat 0.x minor bumps as major and won't use ast-types@0.14.x for react-docgen even on fresh installations. So even if this is just a minor version bump it still requires a new release.

[Brianzchen]

Note that you can't fix this in your project without using e.g. resolutions in yarn. Package managers treat 0.x minor bumps as major and won't use ast-types@0.14.x for react-docgen even on fresh installations. So even if this is just a minor version bump it still requires a new release.

In case anyone is interested in what this means, in your package.json just add a resolutions key like so

  "resolutions": {
    "ast-types": "^0.14.0"
  },

[idbartosz]

bump, @danez when we can expect a release containing this update?

[jquense]

please share the maintenance burden with more people. many projects rely on this project and folks would be happy to help out. It's totally understandable @danez to not have a ton of time to devote to this project, please enable others to share the burden.

[danez]

I just did a release, I can't change the situation, I don't have admin access.

[jquense]

@gaearon or @bvaughn can we give @danez here admin access to this repo?

[bvaughn]

Sure. Done.