"babel-loader@7.1.2" has unmet peer dependency "webpack@2 || 3"

[alansouzati]

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

Report a bug

What is the current behavior?

The following structure in peerDependency does not show any warning with npm install.

  "peerDependencies": {
    "babel-core": "6 || 7 || ^7.0.0-alpha || ^7.0.0-beta || ^7.0.0-rc",
    "webpack": "2 || 3"
  },

https://github.com/babel/babel-loader/blob/master/package.json#L19

Replacing "webpack": "2 || 3" with "webpack": "^2.0.0 || ^3.0.0" removes the warning.

FYI the peer webpack version is set to 3.4.1
If the current behavior is a bug, please provide the steps to reproduce.

Run yarn install

What is the expected behavior?

No warnings

Please mention your node.js, yarn and operating system version.

Node: 6.11.x
Yarn: 1.1.0
OSx 10

[edmorley]

Hi!

Using yarn 1.2.1, node 8.6.0, MSYS2 under Windows x64, I cannot reproduce (I get two react releated peer dependency warnings instead, but they seem legit).

@alansouzati, could you confirm this is fixed in latest yarn? :-)

For reference, I used the following STR:

1. git clone https://github.com/babel/babel-loader
2. cd babel-loader
3. yarn install

[BYK]

I think we've fixed this with the 1.2.0 line. Thanks a lot @edmorley for checking :)

[reinseth]

I can still reproduce this error.

Steps to reproduce:

mkdir yarn-test
cd yarn-test
yarn init
yarn add -D babel-loader

Gives the following output:

yarn add v1.2.1
info No lockfile found.
[1/4] Resolving packages...
[2/4] Fetching packages...
[3/4] Linking dependencies...
warning "babel-loader@7.1.2" has unmet peer dependency "babel-core@6 || 7 || ^7.0.0-alpha || ^7.0.0-beta || ^7.0.0-rc".
warning "babel-loader@7.1.2" has unmet peer dependency "webpack@2 || 3".
[4/4] Building fresh packages...
success Saved lockfile.
success Saved 17 new dependencies.
├─ babel-loader@7.1.2
├─ big.js@3.2.0
├─ commondir@1.0.1
├─ emojis-list@2.1.0
├─ find-cache-dir@1.0.0
├─ find-up@2.1.0
├─ json5@0.5.1
├─ loader-utils@1.1.0
├─ locate-path@2.0.0
├─ make-dir@1.0.0
├─ minimist@0.0.8
├─ mkdirp@0.5.1
├─ p-limit@1.1.0
├─ p-locate@2.0.0
├─ path-exists@3.0.0
├─ pify@2.3.0
└─ pkg-dir@2.0.0
Done in 1.15s.

Node: v8.6.0
Yarn: 1.2.1
OS: Ubuntu 16.04

[edmorley]

@reinseth, the error is correct in that example - those dependencies are missing (that example doesn't install them, unlike the STR in the original post). babel-loader 7.1.2 has a peerDependencies that includes babel-core and webpack, but you're not installing them:
https://github.com/babel/babel-loader/blob/v7.1.2/package.json#L17-L20

See the installation instructions here:
https://github.com/babel/babel-loader#install

[reinseth]

Ah, thanks, I missed that. But there is still something interesting going on:
If I install webpack babel-core babel-loader everything is fine. If I also install babel-cli, however, I get the same error:

$ cat package.json
{
  "name": "yarn-test",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": {
    "babel-cli": "^6.26.0",
    "babel-core": "^6.26.0",
    "webpack": "^3.8.1"
  }
}

$ yarn add babel-loader
yarn add v1.2.1
[1/4] Resolving packages...
[2/4] Fetching packages...
info fsevents@1.1.2: The platform "linux" is incompatible with this module.
info "fsevents@1.1.2" is an optional dependency and failed compatibility check. Excluding it from installation.
[3/4] Linking dependencies...
warning "babel-loader@7.1.2" has unmet peer dependency "babel-core@6 || 7 || ^7.0.0-alpha || ^7.0.0-beta || ^7.0.0-rc".
[4/4] Building fresh packages...
success Saved lockfile.
success Saved 5 new dependencies.
├─ babel-loader@7.1.2
├─ commondir@1.0.1
├─ find-cache-dir@1.0.0
├─ make-dir@1.0.0
└─ pkg-dir@2.0.0
Done in 1.64s.

[florianbepunkt]

Same here. I also get this error as soon as I also install babel-cli.

[hpg-mheck]

Me three. Reprouced this today in a sterile development environment being set up from scratch with @latest everything. babel-core, babel-loader, babel-cli. Getting complaints as if babel-core 7.x is a requirement, when it isn't out yet.

[CodeSigils]

This solved it for me on ubuntu 16.04 -- node v8.9.0 lts/carbon -- npm 5.5.1 -- yarn 1.2.1:
yarn add babel-loader@8.0.0-beta.0 @babel/core@next @babel/preset-env@next webpack

[hpg-mheck]

Yeah, that shut the yarn complaints up, but left me with a bunch of other problems.

Groan. Anything with references to "@next" "@latest" and crap like that is going to break in about a week. In the interests of preserving the sanity of anyone finding this while pulling their hair out, here is a consistent package.json hard version set that seems to work for me at the moment, with yarn, in a Visual Studio 2017 environment, writing Office Add-in stuff, right now, today, 03OCT2017:

{ "name": "yadda-whatever", "version": "1.0.0", "main": "index.js", "license": "MIT", "devDependencies": { "babel-loader": "6.4.0", "babel-preset-es2015": "6.24.1", "babel-preset-react": "6.24.1", "babel-preset-stage-1": "6.24.1", "webpack": "2.6.1", "webpack-dev-server": "2.4.5" }, "dependencies": { "alt": "^0.18.6", "babel-core": "6.24.1", "jshashes": "^1.0.7", "office-ui-fabric-react": "^5.18.0", "react": "15.4.2", "react-dom": "15.4.2" } }

Hopefully that at least helps some people landing on this problem.