Can't use a CRA project inside Yarn Workspaces

[thomas-jeepe]

Is this a bug report?

Yes

Can you also reproduce the problem with npm 4.x?

I am using npm 4.6.1 and its a yarn specific bug anyways.

Which terms did you search for in User Guide?

I simply searched the github repo for workspace and yarn workspace I didn't see a relevant error message/issue.

Environment

1. node -v: 8.4.0
2. npm -v: 4.6.1
3. yarn --version: 0.27.5
4. npm ls react-scripts: Empty (no scripts to use)

Then, specify:

1. Operating system: OSX El Capitan 10.11.6

Steps to Reproduce

https://github.com/thomas-jeepe/err-demo

1. mkdir err-demo
2. cd err-demo
3. touch .yarnrc
4. echo "workspaces-experimental true" > .yarnrc
5. touch package.json
6. Write

{
  "name": "meme",
  "version": "1.0.0",
  "main": "index.js",
  "private": true,
  "workspaces": ["packages/*"]
}

to package.json
7. mkdir packages
8. cd packages
9. create-react-app test

Or: https://github.com/thomas-jeepe/err-demo/

Expected Behavior

create-react-app would use the tools installed at the workspace level.

Actual Behavior

Doesn't find the tools and just complains:

Aborting installation.
Unexpected error. Please report it as a bug:
{ Error: Cannot find module '/Users/PenguinSoccer/code/js/err-demo/packages/test/node_modules/react-scripts/package.json'
    at Function.Module._resolveFilename (module.js:489:15)
    at Function.Module._load (module.js:439:25)
    at Module.require (module.js:517:17)
    at require (internal/module.js:11:18)
    at checkNodeVersion (/Users/PenguinSoccer/.config/yarn/global/node_modules/create-react-app/createReactApp.js:476:23)
    at getPackageName.then.then.then.packageName (/Users/PenguinSoccer/.config/yarn/global/node_modules/create-react-app/createReactApp.js:285:7)
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:188:7) code: 'MODULE_NOT_FOUND' } 

Reproducible Demo

https://github.com/thomas-jeepe/err-demo/

So, just using regular logic, it seems that create-react-app is unaware about yarn workspaces, which install at the package level node_modules rather than for each individual folder in the workspace.

create-react-app goes for the folder's node_modules when the node_modules are kept in the workspace root.

Although from my understanding, yarn attempts to link node_modules in each directory to the root workspace, so then I don't know what the issue is.

Whether create-react-app should support yarn workspaces is up to you guys and low priority for me, since I probably won't use it anyway (think its a cool project though :))

[wgoodall01]

I am also experiencing this issue.

Because Yarn hoists package installs from the child workspaces into the parent package, the package.json isn't where create-react-app thinks it should be.

A workaround for this issue is to run create-react-app in a separate directory from the one with yarn workspaces enabled, then delete <react app>/node_modules, move the react app into the parent project, and then run yarn install again.

My system info

$ uname -srvo
Linux 4.4.0-93-generic #116-Ubuntu SMP Fri Aug 11 21:17:51 UTC 2017 GNU/Linux

$ lsb_release -rcd
Description:	Ubuntu 16.04.3 LTS
Release:	16.04
Codename:	xenial

$ node --version
v8.4.0

$ npm --version
y5.4.1

$ yarn --version
1.0.1

[rulonder]

I am experiencing the same problem, But might it be a yarn workspaces problem? In other words, is there any way that create-react-app can know where the applicable node_modules directory is located without making the guess that is in the package folder?

I think this is not Yarn fault, it's because of tools which search for node_modules by themself to show you a error, some info or other stuff and it doesn't go in upper level, that's why. Because Yarn with workspaces install almost all node_modules in project dir, not the workspace dir. Try to use it without create-react-app but for e.g. with simple project (express or smth) you will see it works :)

[rulonder]

@bsvipas That's right, create-react-app was using an absolute path, I manage to fix it using a relative one. I just submitted a pull request.
#3176

[rulonder]

Nah, that only works with the local npm installation.