[Fix] Null check rootNode before calling getScope with it

[crnhrv]

I'm getting this error while linting some valid React/TS code after upgrading to the latest version (7.34.2):

Stack trace

Oops! Something went wrong! :(

  ESLint: 8.57.0
  
  TypeError: Missing required argument: node.
  Occurred while linting ./OptionsTable.tsx:599
  Rule: "react/display-name"
      at SourceCode.getScope (./node_modules/eslint/lib/source-code/source-code.js:773:19)
      at getScope (./node_modules/eslint-plugin-react/lib/util/eslint.js:19:23)
      at resolveValueForIdentifierNode (./node_modules/eslint-plugin-react/lib/util/propTypes.js:378:21)
      at buildReactDeclarationTypes (./node_modules/eslint-plugin-react/lib/util/propTypes.js:420:5)
      at ./node_modules/eslint-plugin-react/lib/util/propTypes.js:788:39
      at iterateProperties (./node_modules/eslint-plugin-react/lib/util/propTypes.js:71:7)
      at ./node_modules/eslint-plugin-react/lib/util/propTypes.js:773:23
      at Array.forEach (<anonymous>)
      at DeclarePropTypesForTSTypeAnnotation.convertReturnTypeToPropTypes (./node_modules/eslint-plugin-react/lib/util/propTypes.js:762:34)
      at DeclarePropTypesForTSTypeAnnotation.searchDeclarationByName (./node_modules/eslint-plugin-react/lib/util/propTypes.js:667:14)

I don't really understand enough about the codebase to say whether this is the correct fix, or if this really should be passing in node instead of rootNode to getScope or something like that. This resolves the immediate issue for me at least and seemed reasonable to check the value is valid before it tries to call something that requires it.

[ljharb]

Thanks - we'd need a regression test in order to land this tho.

[crnhrv]

@ljharb I've attempted to add some regression tests by trying to find a minimal reproduction. I think the issue relates to using ReturnType<typeof object> for the type parameter for a component, but I don't really know the details.

I get the expected failure without the nullcheck:

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.76%. Comparing base (417e1ca) to head (f877a50).

❗ Current head f877a50 differs from pull request most recent head e27ef81

Please upload reports for the commit e27ef81 to get more accurate results.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3762      +/-   ##
==========================================
- Coverage   97.79%   97.76%   -0.04%     
==========================================
  Files         134      134              
  Lines        9613     9614       +1     
  Branches     3486     3487       +1     
==========================================
- Hits         9401     9399       -2     
- Misses        212      215       +3     

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[crnhrv]

I see that code coverage is failing on some indirect changes related to code beneath a node.type === 'TSParenthesizedType' conditional. Not sure why that would happen, but is this code actually necessary since TSParenthesizedType seems to no longer be generated as a node type?

[ljharb]

@crnhrv that PR seems to be in v5 of the parser, but we still support down to v2

[ljharb]

wonderful, thanks! don't worry about the coverage.

[crnhrv]

Cool, thanks for the help. Will leave it with you then