Postinstall script is not being executed

[aamorozov]

Do you want to request a feature or report a bug?

Bug

What is the current behavior?

Postinstall script specified in the package.json is not being executed after yarn add PACKAGE_NAME

If the current behavior is a bug, please provide the steps to reproduce.

If it can depend on the specifics of the script I can put together a repo to reproduce.

What is the expected behavior?
Postinstall script should be executed after yarn add installs the package. The script is being installed without any issues within npm install.

Please mention your node.js, yarn and operating system version.
node - 9.7.1
yarn - 1.5.1
MacOS Sierra

[rally25rs]

From a quick test on OSX, Node 8.10, yarn 1.5.1 it seemed to work OK:

~/Projects/yarn-test/pkgB 🐒   cat ../pkgA/package.json
{
  "name": "pkgA",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "scripts": {
    "postinstall": "echo 'POST' > post.txt"
  }
}

~/Projects/yarn-test/pkgB 🐒   yarn add file:../pkgA
yarn add v1.5.1
[1/4] 🔍  Resolving packages...
[2/4] 🚚  Fetching packages...
[3/4] 🔗  Linking dependencies...
[4/4] 📃  Building fresh packages...
success Saved 1 new dependency.
info Direct dependencies
└─ pkgA@1.0.0
info All dependencies
└─ pkgA@1.0.0
✨  Done in 0.14s.

~/Projects/yarn-test/pkgB 🐒   cat node_modules/pkgA/post.txt
POST

(adding pkgA to pkgB runs pkgA's postinstall script, creating post.txt)

Could you provide a full example?

[Tom-Bonnike]

@rally25rs, your test seems to work fine.

But I can confirm that this is an issue with my package: clean-slate-lint.

Yarn:

$ yarn --version
1.5.1

$ yarn add -D clean-slate-lint
yarn add v1.5.1
warning package.json: No license field
warning test@1.0.0: No license field
[1/4] 🔍  Resolving packages...
[2/4] 🚚  Fetching packages...
[3/4] 🔗  Linking dependencies...
[4/4] 📃  Building fresh packages...
success Saved 1 new dependency.
info Direct dependencies
└─ clean-slate-lint@1.0.2
info All dependencies
└─ clean-slate-lint@1.0.2
warning test@1.0.0: No license field
✨  Done in 2.43s.

No message and nothing was added to the package.json as expected with this package.
Content of the package.json here: https://github.com/Tom-Bonnike/clean-slate/blob/master/package.json

Npm:

$ npm i --save-dev clean-slate-lint

> husky@0.15.0-rc.9 install /Users/tombonnike/Desktop/test/node_modules/husky
> node lib/installer/bin install

husky > setting up git hooks
husky > done

> clean-slate-lint@1.0.2 postinstall /Users/tombonnike/Desktop/test/node_modules/clean-slate-lint
> ./bin/post-install.js

✅  clean-slate post-commit hooks setup succeeded.

+ clean-slate-lint@1.0.2
added 121 packages from 66 contributors, removed 62 packages and updated 500 packages in 43.483s

[Tom-Bonnike]

As a smaller reproduction case:

$ cat ./pkgA/package.json
{
  "name": "pkgA",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "scripts": {
    "postinstall": "node test.js"
  }
}

$ cat ./pkgA/test.js
#!/usr/bin/env node
console.log('FOO BAR')

$ yarn add -D file:./pkgA
yarn add v1.5.1
warning package.json: No license field
warning test@1.0.0: No license field
[1/4] 🔍  Resolving packages...
[2/4] 🚚  Fetching packages...
[3/4] 🔗  Linking dependencies...
[4/4] 📃  Building fresh packages...
success Saved 1 new dependency.
info Direct dependencies
└─ pkgA@1.0.0
info All dependencies
└─ pkgA@1.0.0
warning test@1.0.0: No license field
✨  Done in 0.24s.

FOO BAR isn’t logged.

[AviVahl]

Yeah, happens for the latest sinon version as well.
npm i outputs:

> sinon@4.5.0 postinstall C:\projects\postinstall\node_modules\sinon
> node scripts/support-sinon.js

Have some ❤️ for Sinon? You can support the project via Open Collective:
 > https://opencollective.com/sinon/donate

while with yarn, the message isn't shown. (I personally prefer not to see the message, heh; feels like an abuse in this case)

Could be that the postinstall runs, but output isn't connected to stdout?

[aamorozov]

As an update, the script is being executed for me with Yarn v. 1.6. However, the output from the script is not being populated within cli.

[nevir]

Same thing on 1.7. The script is being run, but no stdout/stderr is visible (unless the script fails).

Is there a way for a postinstall script to flag that it wants some output printed as part of the regular install flow (e.g. advisory messages)?