WIP: feat: add experimental virtual code cache for faster type-aware linting

[baseballyama]

Took benchmark in https://github.com/mcous/eslint-svelte-ts-perf repo.

1. Lint time without this PR

% time pnpm lint:svelte:slow

> eslint-svelte-ts-perf@0.0.1 lint:svelte:slow /Users/baseballyama/git/eslint-svelte-ts-perf
> eslint -c eslint.slow.config.js "src/lib/**/*.svelte"


/Users/baseballyama/git/eslint-svelte-ts-perf/src/lib/component.svelte
  12:3   error  Unexpected console statement  no-console
  19:21  error  Unexpected console statement  no-console

✖ 2 problems (2 errors, 0 warnings)

 ELIFECYCLE  Command failed with exit code 1.
pnpm lint:svelte:slow  20.82s user 1.56s system 101% cpu 22.117 total

2. Lint time with this PR

% time pnpm lint:svelte:slow

> eslint-svelte-ts-perf@0.0.1 lint:svelte:slow /Users/baseballyama/git/eslint-svelte-ts-perf
> eslint -c eslint.slow.config.js "src/lib/**/*.svelte"


/Users/baseballyama/git/eslint-svelte-ts-perf/src/lib/component.svelte
  12:3   error  Unexpected console statement  no-console
  19:21  error  Unexpected console statement  no-console

✖ 2 problems (2 errors, 0 warnings)

 ELIFECYCLE  Command failed with exit code 1.
pnpm lint:svelte:slow  7.40s user 2.02s system 75% cpu 12.548 total

3. Lint time with this PR and cache

% time pnpm lint:svelte:slow

> eslint-svelte-ts-perf@0.0.1 lint:svelte:slow /Users/baseballyama/git/eslint-svelte-ts-perf
> eslint -c eslint.slow.config.js "src/lib/**/*.svelte"


/Users/baseballyama/git/eslint-svelte-ts-perf/src/lib/component.svelte
  12:3   error  Unexpected console statement  no-console
  19:21  error  Unexpected console statement  no-console

✖ 2 problems (2 errors, 0 warnings)

 ELIFECYCLE  Command failed with exit code 1.
pnpm lint:svelte:slow  4.19s user 1.03s system 121% cpu 4.306 total

[changeset-bot]

⚠️ No Changeset found

Latest commit: c385c7b

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

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[github-actions]

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npm i https://pkg.pr.new/svelte-eslint-parser@c385c7b

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View Commit

[coveralls]

Pull Request Test Coverage Report for Build 21560162352

Details

• 1275 of 1696 (75.18%) changed or added relevant lines in 15 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-2.5%) to 92.211%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/virtual-code/dts-generator.ts	22	25	88.0%
src/virtual-code/project-root.ts	42	45	93.33%
src/virtual-code/tsconfig-generator.ts	114	118	96.61%
src/virtual-code/file-scanner.ts	70	75	93.33%
src/parser/index.ts	10	17	58.82%
src/virtual-code/tsconfig-reader.ts	73	85	85.88%
src/virtual-code/hash.ts	117	141	82.98%
src/parser/typescript/index.ts	10	56	17.86%
src/virtual-code/import-rewriter.ts	281	328	85.67%
src/parser/virtual-code-initializer.ts	30	124	24.19%

Totals
Change from base Build 21375485649:	-2.5%
Covered Lines:	11957
Relevant Lines:	12851

---

💛 - Coveralls