Yarn: The package undefined@undefined requires a flat dependency graph

Created on 24 Aug 2017 · 7Comments · Source: yarnpkg/yarn

If you run yarn add [email protected] in an empty folder, the output is

yarn add v0.28.4
info No lockfile found.
[1/4] 🔍  Resolving packages...
error The package undefined@undefined requires a flat dependency graph. Add `"flat": true` to your package.json and try again.
info Visit https://yarnpkg.com/en/docs/cli/add for documentation about this command.

The same happens with yarn 0.27.5. Tested on macOS Sierra

npm install [email protected] works fine

Source

Artur-

Most helpful comment

Same here, but with polymer-cli.

daniele-orlando on 24 Aug 2017

👍3

All 7 comments

yarn add [email protected] also works

Artur- on 24 Aug 2017

The cause seems to be that 6.1.2 depends on @polymer/test-fixture 3.0.0-pre.1, which defines "flat": true. The error message is a bit... uninformative

Artur- on 24 Aug 2017

Same here, but with polymer-cli.

daniele-orlando on 24 Aug 2017

👍3

Is this still happening with more recent versions of Yarn?

BYK on 20 Oct 2017

This is still happening with yarn 1.3.2 with @polymer/app-layout

cheungnj on 2 Nov 2017

I'm also getting this with yarn 1.3.2. Not sure what exactly is causing it though (I suspect Polymer) how can I track that down?

evancaldwell on 14 Nov 2017

I found the cause of this issue, the error message flatGlobalError expects two arguments for package name and version, but they aren't being passed. It's on line 39167 of cli.js, just change this.reporter.lang('flatGlobalError') to this.reporter.lang('flatGlobalError', info.name, info.version).

I'm working on a patch now.