feat(typescript-estree): add type checker wrapper APIs to ParserServicesWithTypeInformation

[JoshuaKGoldberg]

PR Checklist

• Addresses an existing open issue: fixes Make a "shortcut" API around TypeScript for node types #6244
• That issue was marked as accepting prs
• Steps in CONTRIBUTING.md were taken

Overview

Adds to ParserServicesWithTypeInformation the two most commonly used TypeScript type checking APIs: getSymbolAtLocation and getTypeAtLocation. Then converts all places in code that I could find that used either after immediately retrieving the TS node for an ES node.

Also applies a few standardizations that helped me find-and-replace:

• const services = util.getParserServices(context) - not a variable named parserServices, or variables from { ... }
• const checker = services.program.getTypeChecker() - not a variable named typeChecker or types, and not an intermediate program variable

Updates the Custom Rules docs page to reflect this.

[typescript-eslint]

Thanks for the PR, @JoshuaKGoldberg!

typescript-eslint is a 100% community driven project, and we are incredibly grateful that you are contributing to that community.

The core maintainers work on this in their personal time, so please understand that it may not be possible for them to review your work immediately.

Thanks again!

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[nx-cloud]

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✅ Successfully ran 47 targets

• Node 14 - nx test eslint-plugin --coverage=false
• Node 18 - nx test eslint-plugin
• Node 14 - nx test typescript-estree --coverage=false
• nx run-many --target=lint --parallel
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test ast-spec --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test type-utils --coverage=false
• Node 14 - nx test eslint-plugin-tslint --coverage=false
• Node 14 - nx test utils --coverage=false
• Node 18 - nx test typescript-estree
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test eslint-plugin-internal --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test parser --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test scope-manager --coverage=false
• Node 14 - nx test visitor-keys --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test visitor-keys
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test utils
• nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test type-utils
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=typecheck --parallel
• nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test eslint-plugin-internal
• Node 18 - nx test eslint-plugin-tslint
• Node 18 - nx test scope-manager
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test ast-spec
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=build --parallel --exclude website
• Node 18 - nx test parser
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=build --parallel --exclude website
• nx run-many --target=build --parallel --exclude website

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[codecov]

Codecov Report

Merging #6404 (506bf57) into v6 (1c3f470) will decrease coverage by 0.28%.
The diff coverage is 97.73%.

❗ Current head 506bf57 differs from pull request most recent head e7977f1. Consider uploading reports for the commit e7977f1 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##               v6    #6404      +/-   ##
==========================================
- Coverage   91.87%   91.60%   -0.28%     
==========================================
  Files         359      355       -4     
  Lines       12400    12155     -245     
  Branches     3653     3581      -72     
==========================================
- Hits        11393    11134     -259     
- Misses        703      723      +20     
+ Partials      304      298       -6     

Flag	Coverage Δ
unittest	91.60% <97.73%> (-0.28%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...ges/type-utils/src/getConstrainedTypeAtLocation.ts	0.00% <0.00%> (ø)
packages/type-utils/src/getDeclaration.ts	0.00% <0.00%> (ø)
...ages/typescript-estree/src/createParserServices.ts	71.42% <71.42%> (ø)
...gin-internal/src/rules/no-poorly-typed-ts-props.ts	87.50% <100.00%> (-1.39%)	⬇️
...lugin-internal/src/rules/plugin-test-formatting.ts	79.76% <100.00%> (ø)
packages/eslint-plugin-tslint/src/rules/config.ts	97.22% <100.00%> (ø)
packages/eslint-plugin/src/rules/await-thenable.ts	100.00% <100.00%> (ø)
...eslint-plugin/src/rules/consistent-type-exports.ts	97.67% <100.00%> (-0.03%)	⬇️
packages/eslint-plugin/src/rules/dot-notation.ts	96.29% <100.00%> (-0.14%)	⬇️
...gin/src/rules/naming-convention-utils/validator.ts	96.79% <100.00%> (-0.03%)	⬇️
... and 62 more

[bradzacher]

I'm happy with this! Noice