tools: migrate to ESLint flat config and update ESLint to v9.2.0

[targos]

Closes: https://github.com/nodejs/node/issues/52567

Not completely ready. I have to double check some things because there are reported errors.

I'm opening the PR to ask a question: For now, I put the entire config in one file. I would like to split it into multiple files to make it more readable but I'm not sure what approach to take. My current idea is to create a new folder, probably somewhere in tools.

[nodejs-github-bot]

Review requested:

• [ ] @nodejs/web-standards

[targos]

@nodejs/linting

[aduh95]

For now, I put the entire config in one file. I would like to split it into multiple files to make it more readable but I'm not sure what approach to take. My current idea is to create a new folder, probably somewhere in tools.

To me, the most obvious choice would be to have them in each directory (e.g. lib/eslint.config.mjs, test/eslint.config.mjs)

[targos]

For now, I put the entire config in one file. I would like to split it into multiple files to make it more readable but I'm not sure what approach to take. My current idea is to create a new folder, probably somewhere in tools.

To me, the most obvious choice would be to have them in each directory (e.g. lib/eslint.config.mjs, test/eslint.config.mjs)

I think this would be confusing, because they would not be ESLint config files, just partials for the real config, and it would make people think they work like the old config system.

[aduh95]

Maybe we can use an non-confusing name, lib/eslint.partialconfig.mjs or whatnot.

[targos]

SGTM. I'll wait a few days to see if there are other suggestions.

[targos]

Done! I went with eslint.config_partial.mjs so I could colocate it with eslint.config_utils.mjs in tools.

[targos]

Looks like lib/eslint.config_partial.mjs is picked up by js2c.cc. Not sure what's the best way to ignore it. /cc @joyeecheung

[anonrig]

@targos Can we also enable indentation rule for "Makefile" file?

[joyeecheung]

You can hard-code to exclude it from the JS2C like this:

diff --git a/tools/js2c.cc b/tools/js2c.cc
index e0f3d88447..a536b5dcd8 100644
--- a/tools/js2c.cc
+++ b/tools/js2c.cc
@@ -928,6 +928,13 @@ int Main(int argc, char* argv[]) {
   auto mjs_it = file_map.find(".mjs");
   assert(js_it != file_map.end() && mjs_it != file_map.end());

+  auto it = std::find(mjs_it->second.begin(),
+                      mjs_it->second.end(),
+                      "lib/eslint.config_partial.mjs");
+  if (it != mjs_it->second.end()) {
+    mjs_it->second.erase(it);
+  }
+
   std::sort(js_it->second.begin(), js_it->second.end());
   std::sort(mjs_it->second.begin(), mjs_it->second.end());

(Or make it more flexible as another vector to ignore, or make it an argument, or prefix it with a dot and ignore all files beginning with a dot in SearchFiles, if you want)

[joyeecheung]

If you want to ignore all files beginning with a dot, probably just do this (not sure if we have any files starting with a dot that we actually want to include in the binary, I am guessing we don't):

diff --git a/tools/js2c.cc b/tools/js2c.cc
index e0f3d88447..d94fd33a0d 100644
--- a/tools/js2c.cc
+++ b/tools/js2c.cc
@@ -123,6 +123,10 @@ bool SearchFiles(const std::string& dir,
         break;
       }

+      if (StartsWith(dent.name, ".")) {
+        continue;
+      }
+
       std::string path = dir + '/' + dent.name;
       if (EndsWith(path, extension)) {
         files.emplace_back(path);

[targos]

@targos Can we also enable indentation rule for "Makefile" file?

@anonrig Maybe, but it doesn't seem related to what I'm doing here?

[targos]

This is ready for reviews.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/59027/

[targos]

09:25:44 Running JS linter...
09:25:46 
09:25:46 Oops! Something went wrong! :(
09:25:46 
09:25:46 ESLint: 8.57.0
09:25:46 
09:25:46 Error: EMFILE: too many open files, open '/home/iojs/build/workspace/node-test-linter/test/parallel/test-timers-immediate-unref-nested-once.js'

🤔

[MoLow]

Also worth running on a windows machine before landing

[targos]

I developed it on Windows.

[targos]

Note that .\vcbuild.bat lint-js is already broken on Windows on the main branch because of this file: https://github.com/nodejs/node/blob/main/tools/node_modules/eslint/node_modules/eslint

[targos]

Proof it works after deleting the symlink:

PS D:\Git\nodejs\node> .\vcbuild.bat lint-js nobuild noprojgen
Looking for Python
Python found in C:\Users\Targos\AppData\Local\Microsoft\WindowsApps\\python.exe
Python 3.12.3
Looking for NASM
Jonction créée pour Release <<===>> out\Release
running lint-js
PS D:\Git\nodejs\node>

[targos]

Retrying node-test-linter: https://ci.nodejs.org/job/node-test-linter/54555/

[targos]

It's probably https://github.com/eslint/eslint/issues/18301, only fixed in ESLint v9. I'll add the ESLint update to this PR.

[targos]

Blocked on https://github.com/nodejs/node/pull/52889

[targos]

Added the update to ESLint v9

[MoLow]

Triggered https://ci.nodejs.org/job/node-test-linter/54577/console and it failed :(

20:19:04 Running JS linter...
20:19:04 
20:19:04 Oops! Something went wrong! :(
20:19:04 
20:19:04 ESLint: 9.2.0
20:19:04 
20:19:04 ConfigError: Config (unnamed): Key "rules": Key "constructor-super": structuredClone is not defined
20:19:04     at rethrowConfigError (/home/iojs/build/workspace/node-test-linter/tools/node_modules/eslint/node_modules/@humanwhocodes/config-array/api.js:230:8)
20:19:04     at /home/iojs/build/workspace/node-test-linter/tools/node_modules/eslint/node_modules/@humanwhocodes/config-array/api.js:1032:5
20:19:04     at Array.reduce (<anonymous>)
20:19:04     at FlatConfigArray.getConfig (/home/iojs/build/workspace/node-test-linter/tools/node_modules/eslint/node_modules/@humanwhocodes/config-array/api.js:1028:39)
20:19:04     at FlatConfigArray.isFileIgnored (/home/iojs/build/workspace/node-test-linter/tools/node_modules/eslint/node_modules/@humanwhocodes/config-array/api.js:1060:15)
20:19:04     at /home/iojs/build/workspace/node-test-linter/tools/node_modules/eslint/lib/eslint/eslint-helpers.js:548:38
20:19:04     at Array.forEach (<anonymous>)
20:19:04     at findFiles (/home/iojs/build/workspace/node-test-linter/tools/node_modules/eslint/lib/eslint/eslint-helpers.js:537:11)
20:19:04     at async ESLint.lintFiles (/home/iojs/build/workspace/node-test-linter/tools/node_modules/eslint/lib/eslint/eslint.js:847:27)
20:19:04     at async Object.execute (/home/iojs/build/workspace/node-test-linter/tools/node_modules/eslint/lib/cli.js:500:23)

[targos]

It must be running a very old version of node !

[targos]

19:19:01 + node --version
19:19:01 v16.20.2

[richardlau]

19:19:01 + node --version
19:19:01 v16.20.2

FYI https://github.com/nodejs/build/blob/102f630f31a33cf9762e98bfd10da416d472010c/ansible/roles/jenkins-workspace/tasks/main.yml#L131-L134

[targos]

We need to upgrade the host. Node.js 18+ can't run on Ubuntu 18.

Opened https://github.com/nodejs/build/issues/3713

[targos]

Rebased, reworded the first commit so the PR can be squashed, and separated additional fixes from the ESLint update to ease reviews.

(this is still blocked on updates of the build machines)