yarn run command --production doesn't set NODE_ENV like npm does

[esprehn]

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

What is the current behavior?
yarn run --production foo sets NODE_ENV=production.
yarn run foo --production doesn't set NODE_ENV.

npm run foo --production does set NODE_ENV.
(verified with npm 5.6.0)

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

console.log(process.env.NODE_ENV) inside a script executed with 'run'.

What is the expected behavior?
--production should always set NODE_ENV.

Please mention your node.js, yarn and operating system version.
OS X 10.13.3, v8.9.4

[esprehn]

With package.json

  "scripts": {
    "build": "echo NODE_ENV=$NODE_ENV",
  }

I get:

$ yarn run --production build
yarn run v1.3.2
$ echo NODE_ENV=$NODE_ENV
NODE_ENV=production
✨  Done in 0.11s.
$ yarn run build --production
yarn run v1.3.2
$ echo NODE_ENV=$NODE_ENV --production
NODE_ENV= --production

Which seems wrong, it's setting NODE_ENV to neither development or production, but to the flag value with dashes.

[hulkish]

@esprehn

Which seems wrong, it's setting NODE_ENV to neither development or production, but to the flag value with dashes

looks like your line here is the cause: echo NODE_ENV=$NODE_ENV --production

[esprehn]

Ah yeah I misinterpreted the yarn output, thanks. It's not setting NODE_ENV at all there. So the original bug still stands.

[hulkish]

@esprehn i couldn't repro this. This sounds like expected environment behavior.. meaning if you wanted NODE_ENV value to persist.. you would need to do export NODE_ENV=production. Maybe im following the steps in the issue incorrectly?

[hulkish]

@esprehn this test should either confirm or deny the bug, right?

yarn/__tests__/integration.js

Line 83 in 5a24a4d

test('it should be true when NODE_ENV=production', async () => {

[esprehn]

Sorry I wasn't clear, the bug is if you have a script that prints NODE_ENV:

npm run my-script --production
npm run --production my-script

Both set NODE_ENV=production

yarn run my-script --production doesn't.

[hulkish]

shouldn't the above test validate this, though?

[esprehn]

I don't understand that test, but I don't think so. Now that I'm reading the docs more closely and writing examples this looks like a difference with how yarn and npm take arguments.

https://docs.npmjs.com/cli/run-script
npm run-script <command> [--silent] [-- <args>...]

https://yarnpkg.com/lang/en/docs/cli/run/
yarn run [script] [<args>]

yarn passes all args following the script name to the script itself, while npm passes them to npm unless you add a -- delimiter.

So npm is:

npm run <args for npm...> <script name> <more args for npm...> -- <args for script...>

and yarn is:

yarn run <args for yarn...> <script name> <args for script...>

So I think this is by design for how yarn takes arguments when running scripts. Maybe this could be mentioned as a difference on https://yarnpkg.com/lang/en/docs/migrating-from-npm/ That would be really great! :)

[kaylie-alexa]

@esprehn I believe this is the design starting from 1.0.0 so that arguments can be directly passed to scripts without -- double dash dash #4152

Closing this as an issue, but would love if you wanted to contribute to our docs in https://github.com/yarnpkg/website/blob/master/lang/en/docs/cli/run.md or https://github.com/yarnpkg/website/blob/master/lang/en/docs/migrating-from-npm.md