BREAKING: Bump ESLint to ^9.11.1, bump related ESLint dependencies, and rewrite configs to use flat configs

[Mrtenz]

ESLint 8 will be end-of-life from 2024-10-05. ESLint 8 introduced a new config format, which is now the default in ESLint 9, and only opt-out through an environment flag. We could enable that flag and keep the current configs, but it's better to just update the configs now and be done with it.

I've updated all configs to use the new format. The most notable changes are:

• All ESLint-related dependencies are now on the latest version.
• All configs now use ESM, as this is now supported out-of-the-box in ESLint 9.
• I've updated the default ECMAScript version to 2022, which is in line with what the MetaMask extension supports.
• Each config now includes a TypeScript declaration file to support type-checking.

Closes #362.

Breaking changes

All configs

• All packages are now pure ESM, and cannot be imported from a CJS configuration.
  • ESLint 9 supports ESM configurations out of the box.
• The minimum ESLint version is now ^9.11.0, and all configs were updated to use the flat config format.
  • See the migration guide for more information.
• All dependencies have been updated, so some rules have been replaced or removed.

@metamask/eslint-config-typescript

• @typescript-eslint/parser and @typescript-eslint/eslint-plugin are replaced with typescript-eslint@^8.6.0, which is now a peer dependency.
• For proper linting using type information, languageOptions.parserOptions.tsconfigRootDir must be set to the current directory, e.g., using import.meta.dirname.

[socket-security]

New and removed dependencies detected. Learn more about Socket for GitHub ↗︎

Package	New capabilities	Transitives	Size	Publisher
npm/@ampproject/remapping@2.2.1	None	0	76 kB	jridgewell
npm/@babel/plugin-syntax-jsx@7.22.5	None	0	4.13 kB	nicolo-ribaudo
npm/@babel/plugin-syntax-typescript@7.22.5	None	0	6.86 kB	nicolo-ribaudo
npm/@es-joy/jsdoccomment@0.48.0	None	0	121 kB	brettz9
npm/@eslint-community/regexpp@4.11.1	None	0	446 kB	eslint-community-bot
npm/@eslint/config-array@0.18.0	None	0	113 kB	eslintbot
npm/@eslint/eslintrc@3.1.0	filesystem, unsafe	0	668 kB	eslintbot
npm/@eslint/js@9.11.0	None	0	14.2 kB	eslintbot, openjsfoundation
npm/@eslint/object-schema@2.1.4	None	0	55.5 kB	eslintbot
npm/@eslint/plugin-kit@0.2.0	None	0	76.7 kB	eslintbot
npm/@humanwhocodes/retry@0.3.0	None	0	44.3 kB	nzakas
npm/@types/eslint__js@8.42.3	None	0	3.17 kB	types
npm/@types/eslint@9.6.1	None	0	196 kB	types
npm/@types/json-schema@7.0.15	None	0	31.7 kB	types
npm/@types/node@22.5.5	None	0	2.2 MB	types
npm/@typescript-eslint/eslint-plugin@8.6.0	None	0	2.63 MB	bradzacher, jameshenry
npm/@typescript-eslint/parser@8.6.0	None	0	18.7 kB	jameshenry
npm/@typescript-eslint/scope-manager@8.6.0	None	0	602 kB	jameshenry
npm/@typescript-eslint/type-utils@8.6.0	None	0	121 kB	jameshenry
npm/@typescript-eslint/types@8.6.0	None	0	171 kB	jameshenry
npm/@typescript-eslint/typescript-estree@8.6.0	None	0	588 kB	jameshenry
npm/@typescript-eslint/utils@8.6.0	None	0	282 kB	jameshenry
npm/@typescript-eslint/visitor-keys@8.6.0	None	0	19.5 kB	bradzacher, jameshenry
npm/acorn@8.12.1	None	0	538 kB	marijn
npm/browserslist@4.23.3	environment, filesystem	0	63 kB	ai
npm/caniuse-lite@1.0.30001662	None	0	2.1 MB	ai, beneb, caniuse-lite
npm/debug@4.3.7	environment	0	42.1 kB	qix
npm/electron-to-chromium@1.5.27	None	0	148 kB	kilianvalkhof
npm/enhanced-resolve@5.17.1	unsafe	0	212 kB	evilebottnawi
npm/es-module-lexer@1.5.4	None	0	90.9 kB	guybedford
npm/eslint-config-prettier@9.1.0	None	0	20.8 kB	lydell
npm/eslint-plugin-import-x@4.3.0	None	0	683 kB	jounqin
npm/eslint-plugin-jest@28.8.3	filesystem	0	349 kB	aaronabramov, jeysal, jsonp, ...6 more
npm/eslint-plugin-jsdoc@50.2.4	None	0	2.08 MB	gajus
npm/eslint-plugin-n@17.10.3	None	0	437 kB	eslint-community-bot, weiran.zsd
npm/eslint-plugin-prettier@5.2.1	None	0	34.3 kB	jounqin
npm/eslint-plugin-promise@7.1.0	None	0	77.7 kB	eslint-community-bot
npm/eslint-scope@8.0.2	None	0	148 kB	eslintbot
npm/eslint@9.11.0	environment	0	3.3 MB	eslintbot
npm/espree@10.1.0	None	0	76.5 kB	eslintbot
npm/esquery@1.6.0	None	0	1.04 MB	michaelficarra
npm/file-entry-cache@8.0.0	filesystem	0	16 kB	jaredwray
npm/flat-cache@4.0.1	filesystem	0	29.3 kB	jaredwray
npm/flatted@3.3.1	None	0	40.3 kB	webreflection
npm/get-tsconfig@4.8.1	filesystem	0	105 kB	hirokiosame
npm/globals@15.9.0	None	0	174 kB	sindresorhus
npm/globby@13.2.2	None	0	25.1 kB	sindresorhus
npm/graceful-fs@4.2.11	environment, filesystem	0	32.5 kB	isaacs
npm/ignore@5.3.2	None	0	53.6 kB	kael
npm/jsdoc-type-pratt-parser@4.1.0	None	0	245 kB	jsdoc-type-pratt-parser
npm/json-buffer@3.0.1	None	0	5.4 kB	dominictarr
npm/keyv@4.5.4	None	0	27.8 kB	jaredwray
npm/ms@2.1.3	None	0	6.72 kB	styfle
npm/node-gyp@10.2.0	environment, shell	0	1.85 MB	nodejs-foundation
npm/parse-imports@2.2.1	None	0	39.1 kB	tomeraberbach
npm/prettier-plugin-packagejson@2.5.2	None	0	5.55 kB	matzkoh
npm/prettier@3.3.3	environment, filesystem, unsafe	0	7.7 MB	prettier-bot
npm/slashes@3.0.12	None	0	26 kB	chrisackerman
npm/socks@2.8.3	network	0	156 kB	joshglazebrook
npm/sort-package-json@2.10.1	None	0	33.3 kB	keithamus
npm/stable-hash@0.0.4	None	0	5.46 kB	quietshu
npm/synckit@0.9.1	environment	0	55.7 kB	jounqin
npm/tapable@2.2.1	None	0	46.9 kB	sokra
npm/tslib@2.7.0	None	0	86.2 kB	typescript-bot
npm/typescript-eslint@8.6.0	None	0	99.5 kB	jameshenry

🚮 Removed packages: npm/@eslint-community/regexpp@4.10.0, npm/@eslint/eslintrc@3.0.2, npm/@eslint/js@8.57.0, npm/@humanwhocodes/config-array@0.11.14, npm/@humanwhocodes/object-schema@2.0.2, npm/@typescript-eslint/eslint-plugin@8.7.0, npm/@typescript-eslint/parser@8.7.0, npm/@typescript-eslint/scope-manager@7.12.0, npm/@typescript-eslint/types@7.12.0, npm/@typescript-eslint/typescript-estree@7.12.0, npm/@typescript-eslint/utils@7.12.0, npm/@typescript-eslint/visitor-keys@7.12.0, npm/acorn@8.11.3, npm/debug@4.3.4, npm/escalade@3.1.1, npm/eslint-plugin-import-x@0.5.1, npm/eslint-plugin-jest@27.9.0, npm/eslint-plugin-n@16.6.2, npm/eslint-plugin-promise@6.1.1, npm/eslint-visitor-keys@4.0.0, npm/eslint@8.57.0, npm/espree@10.0.1, npm/esquery@1.5.0, npm/flat-cache@3.0.4, npm/flatted@3.2.6, npm/get-tsconfig@4.7.5, npm/globals@15.0.0, npm/graceful-fs@4.2.10, npm/ignore@5.3.1, npm/ms@2.1.2, npm/node-gyp@10.1.0, npm/prettier-plugin-packagejson@2.5.0, npm/semver@7.6.2, npm/socks@2.8.1, npm/sort-package-json@2.10.0, npm/synckit@0.9.0, npm/tslib@2.6.2

View full report↗︎

[socket-security]

👍 Dependency issues cleared. Learn more about Socket for GitHub ↗︎

This PR previously contained dependency changes with security issues that have been resolved, removed, or ignored.

Ignoring: npm/eslint-plugin-jest@28.8.3, npm/node-gyp@10.2.0

View full report↗︎

Next steps

Take a deeper look at the dependency

Take a moment to review the security alert above. Review the linked package source code to understand the potential risk. Ensure the package is not malicious before proceeding. If you're unsure how to proceed, reach out to your security team or ask the Socket team for help at support [AT] socket [DOT] dev.

Remove the package

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To ignore an alert, reply with a comment starting with @SocketSecurity ignore followed by a space separated list of ecosystem/package-name@version specifiers. e.g. @SocketSecurity ignore npm/foo@1.0.0 or ignore all packages with @SocketSecurity ignore-all

[Mrtenz]

@SocketSecurity ignore npm/agentkeepalive@4.5.0
@SocketSecurity ignore npm/make-fetch-happen@10.2.1

Network access expected.

@SocketSecurity ignore npm/@npmcli/fs@2.1.2
@SocketSecurity ignore npm/nopt@6.0.0
@SocketSecurity ignore npm/npmlog@6.0.2
@SocketSecurity ignore npm/unique-slug@3.0.0

New author is ok.

@SocketSecurity ignore npm/gauge@4.0.4
@SocketSecurity ignore npm/@npmcli/move-file@2.0.1
@SocketSecurity ignore npm/are-we-there-yet@3.0.1

Deprecated is ok.

@SocketSecurity ignore npm/eslint-plugin-jest@28.8.3

Seems like a false positive.

[Mrtenz]

This script doesn't have the same functionality as the previous script. It's a bit hard to follow what exactly it was doing, so for the time being, this script simply checks and writes snapshots.

[MajorLift]

Is this safe because consumers always use this package as a devDep? Are we sure this doesn't affect downstream CJS packages?

[MajorLift]

Looking at the eslint v9 migrate guide, looks like we only need to worry about CJS configurations importing from our repo, and that shouldn't be a problem for long since eslint is now set up to use ESM by default?

[Mrtenz]

Consumers can add it and use it even if they use type: commonjs, as long as the config is a .mjs file. I figured we might as well update all places where we consume the libraries since we have to rewrite the majority of the configs anyway.

[MajorLift]

@metamaskbot publish-preview

[Mrtenz]

@SocketSecurity ignore npm/node-gyp@10.2.0

New author is ok.

[MajorLift]

LGTM! Confirmed that the updated config packages can be installed and are functional downstream. IMO any further fixes that may or may not be needed can be handled in separate PRs.