tools: update-eslint.sh does not work with npm@7

[lpinca]

• Version: v15.10.0, npm version 7.5.3
• Platform: Darwin imac.local 20.3.0 Darwin Kernel Version 20.3.0: Thu Jan 21 00:07:06 PST 2021; root:xnu-7195.81.3~1/RELEASE_X86_64 x86_64
• Subsystem: tools

What steps will reproduce the bug?

Running the tools/update-eslint.sh with npm@7 fails with the following error:

npm ERR! code ERESOLVE
npm ERR! Cannot destructure property 'name' of 'node' as it is null.

How often does it reproduce? Is there a required condition?

Always. No required condition.

What is the expected behavior?

The script works without errors.

What do you see instead?

See above.

Additional information

Using the --legacy-peer-deps flag to install eslint-plugin-markdown does not help as it produces a new issue where the eslint-tmp/node_modules/eslint folder is removed.

I can only make it work with something like this

diff --git a/tools/update-eslint.sh b/tools/update-eslint.sh
index d0320ab8f8..69dab66a2c 100755
--- a/tools/update-eslint.sh
+++ b/tools/update-eslint.sh
@@ -8,20 +8,14 @@
 # $BASH_SOURCE[0] to determine directories to work in.
 
 cd "$( dirname "$0" )" || exit
-rm -rf node_modules/eslint
+rm -rf node_modules/eslint node_modules/eslint-plugin-markdown
 (
     mkdir eslint-tmp
     cd eslint-tmp || exit
     npm init --yes
 
     npm install --global-style --no-bin-links --production --no-package-lock eslint@latest
-
-    (
-        cd node_modules/eslint || exit
-
-        npm install --no-bin-links --production --no-package-lock eslint-plugin-markdown@latest
-    )
-
+    npm install --global-style --no-bin-links --production --no-package-lock eslint-plugin-markdown@latest
 
     # Use dmn to remove some unneeded files.
     npx dmn@2.2.2 -f clean
@@ -31,4 +25,6 @@ rm -rf node_modules/eslint
 )
 
 mv eslint-tmp/node_modules/eslint node_modules/eslint
+mv eslint-tmp/node_modules/eslint-plugin-markdown node_modules/eslint-plugin-markdown
+
 rm -rf eslint-tmp/

but that means adding a new folder and some dependencies are probably not deduplicated.

[lpinca]

cc: @nodejs/npm

[ruyadorno]

looks like a legit issue with peer deps in Arborist :

npm verb stack Error: unable to resolve dependency tree
npm verb stack     at Arborist.[failPeerConflict] (<path>/workspace/cli/main/node_modules/@npmcli/arborist/lib/arborist/build-ideal-tree.js:1141:25)
npm verb stack     at Arborist.[loadPeerSet] (<path>/workspace/cli/main/node_modules/@npmcli/arborist/lib/arborist/build-ideal-tree.js:1118:34)
npm verb stack     at processTicksAndRejections (node:internal/process/task_queues:94:5)
npm verb stack     at async Arborist.[buildDepStep] (<path>/workspace/cli/main/node_modules/@npmcli/arborist/lib/arborist/build-ideal-tree.js:836:11)
npm verb stack     at async Arborist.buildIdealTree (<path>/workspace/cli/main/node_modules/@npmcli/arborist/lib/arborist/build-ideal-tree.js:209:7)
npm verb stack     at async Promise.all (index 1)
npm verb stack     at async Arborist.reify (<path>/workspace/cli/main/node_modules/@npmcli/arborist/lib/arborist/reify.js:130:5)
npm verb stack     at async install (<path>/workspace/cli/main/lib/install.js:38:3)
npm verb cwd <path>/ruyadorno/nodejs/tools/eslint-tmp/node_modules/eslint
npm verb Darwin 19.6.0
npm verb argv "<path>/ruyadorno/nodejs/out/Release/node" "<path>/workspace/cli/main" "install" "--no-bin-links" "--production" "--no-package-lock" "eslint-plugin-markdown@latest" "--loglevel=verbose"
npm verb node v16.0.0-pre
npm verb npm  v7.6.0
npm ERR! code ERESOLVE
npm verb stack TypeError: Cannot destructure property 'name' of 'node' as it is null.
npm verb stack     at printNode (<path>/workspace/cli/main/lib/utils/explain-dep.js:29:5)
npm verb stack     at explainNode (<path>/workspace/cli/main/lib/utils/explain-dep.js:13:3)
npm verb stack     at explainEresolve (<path>/workspace/cli/main/lib/utils/explain-eresolve.js:24:24)
npm verb stack     at report (<path>/workspace/cli/main/lib/utils/explain-eresolve.js:50:3)
npm verb stack     at module.exports (<path>/workspace/cli/main/lib/utils/error-message.js:22:24)
npm verb stack     at errorHandler (<path>/workspace/cli/main/lib/utils/error-handler.js:175:15)
npm verb stack     at <path>/workspace/cli/main/lib/npm.js:125:9
npm verb stack     at processTicksAndRejections (node:internal/process/task_queues:94:5)
npm verb cwd <path>/ruyadorno/nodejs/tools/eslint-tmp/node_modules/eslint
npm verb Darwin 19.6.0
npm verb argv "<path>/ruyadorno/nodejs/out/Release/node" "<path>/workspace/cli/main" "install" "--no-bin-links" "--production" "--no-package-lock" "eslint-plugin-markdown@latest" "--loglevel=verbose"
npm verb node v16.0.0-pre
npm verb npm  v7.6.0
npm ERR! Cannot destructure property 'name' of 'node' as it is null.
npm verb exit 1

I'll open an issue on our end to make sure we follow up with it.

[ruyadorno]

@lpinca I'm just trying to reproduce it here and now I realize the current script is cding into a node_modules folder? That's not a supported use case as far as I'm aware.

What is the end goal here? I'm thinking that your proposed change (from the attached patch diff) might actually be a much better way to handle it - but again I don't have the full context here.

[lpinca]

Yes current script is adding eslint-plugin-markdown as a dependency of eslint after installing it. I don't know what are the motivations to do that. Perhaps moving only one directory and reduce dependencies?

Refs: #13895

cc: @Trott

I'm fine with the above patch if there is consensus.

[aduh95]

How does the git diff looks with this patch? Do you see a bunch of added files or does it just move them?

[Trott]

IIRC, the reason we cd into the node_modules/eslint is so that eslint can have its own node_modules so that we can move the eslint directory to a different location later and still have everything work.