chore: upgrade eslint

[david-luna]

Updates eslint to v9 and switches to the new flat config.

[david-luna]

with the package-lock.json state from main you can install with warnings. A cleanup of node_modules and a new install gives this error

Run npm ci
npm ERR! code ERESOLVE
npm ERR! ERESOLVE could not resolve
npm ERR! 
npm ERR! While resolving: eslint-plugin-import@2.29.1
npm ERR! Found: eslint@9.1.1
npm ERR! node_modules/eslint
npm ERR!   dev eslint@"^9.1.0" from the root project
npm ERR!   peer eslint@"^6.0.0 || ^7.0.0 || >=8.0.0" from @eslint-community/eslint-utils@[4](https://github.com/elastic/elastic-otel-node/actions/runs/8882442044/job/24387150370?pr=155#step:6:5).4.0
npm ERR!   node_modules/@eslint-community/eslint-utils
npm ERR!     @eslint-community/eslint-utils@"^4.2.0" from eslint@9.1.1
npm ERR!     @eslint-community/eslint-utils@"^4.1.2" from eslint-plugin-es-x@7.[5](https://github.com/elastic/elastic-otel-node/actions/runs/8882442044/job/24387150370?pr=155#step:6:6).0
npm ERR!     node_modules/eslint-plugin-es-x
npm ERR!       eslint-plugin-es-x@"^7.5.0" from eslint-plugin-n@17.3.1
npm ERR!       node_modules/eslint-plugin-n
npm ERR!         dev eslint-plugin-n@"^17.2.0" from the root project
npm ERR!     1 more (eslint-plugin-n)
npm ERR!   5 more (eslint-compat-utils, eslint-config-prettier, ...)
npm ERR! 
npm ERR! Could not resolve dependency:
npm ERR! peer eslint@"^2 || ^3 || ^4 || ^5 || ^[6](https://github.com/elastic/elastic-otel-node/actions/runs/8882442044/job/24387150370?pr=155#step:6:7) || ^7.2.0 || ^8" from eslint-plugin-import@2.29.1
npm ERR! node_modules/eslint-plugin-import
npm ERR!   dev eslint-plugin-import@"^2.29.0" from the root project
npm ERR! 
npm ERR! Conflicting peer dependency: eslint@8.5[7](https://github.com/elastic/elastic-otel-node/actions/runs/8882442044/job/24387150370?pr=155#step:6:8).0
npm ERR! node_modules/eslint
npm ERR!   peer eslint@"^2 || ^3 || ^4 || ^5 || ^6 || ^7.2.0 || ^[8](https://github.com/elastic/elastic-otel-node/actions/runs/8882442044/job/24387150370?pr=155#step:6:9)" from eslint-plugin-import@2.2[9](https://github.com/elastic/elastic-otel-node/actions/runs/8882442044/job/24387150370?pr=155#step:6:10).1
npm ERR!   node_modules/eslint-plugin-import
npm ERR!     dev eslint-plugin-import@"^2.29.0" from the root project
npm ERR! 
npm ERR! Fix the upstream dependency conflict, or retry
npm ERR! this command with --force, or --legacy-peer-deps
npm ERR! to accept an incorrect (and potentially broken) dependency resolution.
npm ERR! 
npm ERR! See /home/runner/.npm/eresolve-report.txt for a full report.

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/runner/.npm/_logs/2024-04-29T[17](https://github.com/elastic/elastic-otel-node/actions/runs/8882442044/job/24387150370?pr=155#step:6:18)_00_46_673Z-debug-0.log

It's odd this does not happen in apm-agent-nodejs repo.

[trentm]

It's odd this does not happen in apm-agent-nodejs repo.

Perhaps because apm-agent-nodejs repo has this:

% cat .npmrc
# Workaround unresolvable peerDependencies between graphql, @apollo-server,
# and apollo-server-express. npm v7 (included with node v15) makes these
# peerDependencies issues an install error. Until the community catches up
# and resolves peerDependencies issues or apm-agent-nodejs.git's tests are
# setup to not have competing deps in "devDependencies", we revert to the
# pre-v7 behavior.
# https://docs.npmjs.com/cli/v7/using-npm/config#legacy-peer-deps
legacy-peer-deps=true

[trentm]

Is there an issue or PR on eslint-plugin-import to have it update its peerDeps to include eslint v9?

[david-luna]

Is there an issue or PR on eslint-plugin-import to have it update its peerDeps to include eslint v9?

There is an issue to add support to eslint@9 import-js/eslint-plugin-import#2948

and theres is a draft PR import-js/eslint-plugin-import#2996 so the peerDependencies will be updated in a newer version

[trentm]

Wow, that's a big PR change to eslint-plugin-import.