Codegen flow and typescript parsers infinite loop caused by circular aliases

[leotm]

Description

For libs using ESLint plugin @react-native/eslint-plugin-specs rule @react-native/specs/react-native-modules

when a type alias name matches the RHS, e.g.

import { TurboModule, TurboModuleRegistry } from 'react-native';
import type { CodegenTypes } from 'react-native';

type Double = CodegenTypes.Double; // 👀

ESLint never finishes (the Node process hangs)

a current workaround is to either use the namespace e.g. CodegenTypes.Double everywhere
or rename your type alias to e.g. type _Double = CodegenTypes.Double for now

e.g. appandflow/react-native-safe-area-context#744 (review)

seems like the AST is being parsed like
type Double = CodegenTypes.Double → resolves to Double (same GenericTypeAnnotation TypeAlias) → repeat

digging deeper

react-native/packages/eslint-plugin-specs/react-native-modules.js

Line 37 in d07bd6f

only: [/react-native-codegen\/src\//],

react-native/packages/eslint-plugin-specs/react-native-modules.js

Line 75 in 704c2b1

parser: new RNFlowParser.FlowParser(),

isolates this to codegen flow parser (not the ts one)

i.e. packages\react-native-codegen\src\parsers\flow\parser.js

it looks like getResolvedTypeAnnotation (called indirectly in RNFlowParser/RNModuleParser/RNParserCommons)
is looping infinitely in the for loop so we need to break on circular type aliases

by monkey patching node_modules\@react-native\codegen\lib\parsers\flow\parser.js
managed to get it working so can propose a fix for the flow parser

it looks like it also happens with the ts parser, so can follow-up with a similar (if not the same) fix there too

also tested latest stable

  "resolutions": {
    "@react-native/codegen": "0.87.0"
  },

Steps to reproduce

1. fix: replace deep RN imports with public API appandflow/react-native-safe-area-context#744 (review)
2. yarn validate:eslint

React Native Version

0.85.3, 0.87.0, main

Affected Platforms

Build - Linux, Build - Windows, Build - MacOS

Output of npx @react-native-community/cli info

N/A

Stacktrace or Logs

yarn validate:eslint --debug

MANDATORY Reproducer

appandflow/react-native-safe-area-context#744 (review)

Screenshots and Videos

No response

[react-native-bot]

Warning

Missing reproducer: We could not detect a reproducible example in your issue report. Reproducers are mandatory and we can accept only one of those as a valid reproducer:

• For majority of bugs: send us a Pull Request with the RNTesterPlayground.js edited to reproduce your bug.
• If your bug is UI related: a Snack
• If your bug is build/upgrade related: a project using our Reproducer Template

You can read more about about it on our website: How to report a bug.