feat(typescript-estree): experimental option to cache type checking APIs

[JoshuaKGoldberg]

PR Checklist

• Addresses an existing open issue: fixes Enhancement: Investigate caching type checking APIs #6425
• That issue was marked as accepting prs
• Steps in Contributing were taken

Overview

Applies a thin memoization layer on top of getSymbolAtLocation and getTypeAtLocation.

hyperfine measurements are not very promising:

Package	v6	Memoizing shortcut API	Memoizing type checker
eslint-plugin	21.467 s ± 0.096 s	21.465 s ± 0.121 s	26.675 s ± 0.096 s
typescript-estree	11.755 s ± 0.052 s	11.983 s ± 0.113 s	12.128 s ± 0.045 s

I'm betting I'll want to add caching around the native type checker (checker.getContextualType) too.

I'll probably want to add an EXPERIMENTAL_ option so we can put this in v6 and get easier real world testing.

Co-authored-by: @bradzacher

[typescript-eslint]

Thanks for the PR, @JoshuaKGoldberg!

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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.

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🟥 Failed Commands
Node 18 - nx test typescript-estree

✅ Successfully ran 45 targets

• Node 14 - nx test ast-spec --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test scope-manager --coverage=false
• Node 14 - nx test utils --coverage=false
• 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 14 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test eslint-plugin --coverage=false
• Node 14 - nx run-many --target=build --parallel --exclude website
• Node 14 - nx test eslint-plugin-tslint --coverage=false
• 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 type-utils --coverage=false
• 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 18 - nx test utils
• Node 14 - nx test visitor-keys --coverage=false
• Node 14 - 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=build --parallel --exclude website
• Node 18 - nx test parser
• 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
• nx run-many --target=typecheck --parallel
• Node 18 - nx run-many --target=build --parallel --exclude website
• Node 18 - nx test eslint-plugin-internal
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=lint --parallel
• Node 18 - nx test eslint-plugin-tslint
• Node 18 - nx run-many --target=build --parallel --exclude website
• nx run-many --target=build --parallel --exclude website
• Node 18 - nx test eslint-plugin
• 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
• 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 #6426 (3a8b206) into v6 (c036fe3) will decrease coverage by 0.09%.
The diff coverage is 0.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##               v6    #6426      +/-   ##
==========================================
- Coverage   87.46%   87.38%   -0.09%     
==========================================
  Files         374      374              
  Lines       12879    12891      +12     
  Branches     3811     3813       +2     
==========================================
  Hits        11265    11265              
- Misses       1229     1241      +12     
  Partials      385      385              

Flag	Coverage Δ
unittest	87.38% <0.00%> (-0.09%)	⬇️

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

Impacted Files	Coverage Δ
...ages/typescript-estree/src/createParserServices.ts	26.31% <0.00%> (-45.12%)	⬇️
...pt-estree/src/parseSettings/createParseSettings.ts	85.71% <ø> (ø)

[bradzacher]

hyperfine measurements are not very promising:

What's the command you used to grab the hyperfine measurement?
I've been raw-dogging the entire codebase lint run via ./node_modules/.bin/eslint . (to work around yarn and ensure i run eslint directly).

Do we have a bigger type-aware codebase we can test on?
Maybe we can just turn on every single rule in our codebase for the test run to increase the possibility of cache hits (I know we're fairly conservative in our type-aware linting ATM).

[JoshuaKGoldberg]

yarn lint --skip-nx-cache - it's deep in the edit history. I do want to do more thorough checking, including on the codebase as a whole. And there might be more type checker APIs that should be cached. I like the turning on every rule, good idea!

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✅ Successfully ran 30 targets

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

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[JoshuaKGoldberg]

@bradzacher not-very-promising news on this:

• Running time MEMOIZE_TYPE_CHECKING_APIS=true yarn lint --skip-nx-cache takes ~60 seconds for me - same as time yarn lint
• Running time MEMOIZE_TYPE_CHECKING_APIS=true yarn lint-many runs out of memory (instead of taking ~110 seconds)

I think it'd make sense to ship this change, since it's small and additive and labeled as EXPERIMENTAL_. Thoughts?

[JoshuaKGoldberg]

This was unintentionally auto-closed when we merged the v6 branch 🙃 it'll be recreated.

[JoshuaKGoldberg]

I'm more hopeful about the EXPERIMENTAL_useProjectService parser option (#6754). Closing this for now.

If someone does think this PR would benefit them, feel free to post an explanation why! We can always re-open - or even better, you the reader can open it and take ownership.