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MaxListenersExceededWarning when lerna run --stream with 3+ packages

See original GitHub issue

Expected Behavior

I have 3 packages in my monorepo, each of them have a npm build script.

I run lerna run build --stream from the root folder, I expect to see the live output.

Current Behavior

I see the live output but also:

(node:48783) MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 4 error listeners added. Use emitter.setMaxListeners() to increase limit

Possible Solution

Steps to Reproduce (for bugs)

https://github.com/amaurymartiny/cra-lerna-electron/tree/am-try-no-npm

yarn lint works. yarn lint --stream outputs the warning.

lerna.json

{
  "lerna": "2.11.0",
  "npmClient": "yarn",
  "packages": [
    "packages/*"
  ],
  "useWorkspaces": false,
  "version": "0.1.0"
}

lerna-debug.log

Context

Your Environment

Executable	Version
`lerna --version`	2.11.0
`npm --version`	6.1.0
`yarn --version`	1.7.0
`node --version`	10.1.0

OS	Version
macOS Sierra	10.13.4

Issue Analytics

State:
Created 5 years ago
Reactions:17
Comments:5 (1 by maintainers)

Top GitHub Comments

1reaction

seanconnollydevcommented, Dec 7, 2018

I see the same warning when I try to run bootstrap. bootstrap does not seem to support the --concurrency flag so I’m not sure how I can correct this.

0reactions

hugebducommented, Aug 27, 2019

@evocateur might that be there’s missing .unpipe call upon child’s process exit?

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