Yarn check reports errors after yarn install

[nkovacs]

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

bug

What is the current behavior?
yarn check outputs the following errors:

error "webpack#ajv" is wrong version: expected "5.5.2", got "4.11.8"
error "webpack#ajv-keywords" is wrong version: expected "2.1.1", got "1.5.1"
error "table#ajv" not installed
error "table#ajv-keywords" not installed

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

yarn init -y && yarn add eslint@3.19.0 webpack@3.2.0 && yarn check

What is the expected behavior?
yarn check should not output any errors

Please mention your node.js, yarn and operating system version.
node.js 8.11.3 and 10.11.0
yarn 1.1.0, 1.4.0, 1.7.0, 1.8.0, 1.9.1, 1.9.4 and 1.10.0 (yarn 1.0.0 does not seem to be affected)
debian 8 and 9

This bug was originally reported as #3916 and #3933, and it was fixed in 1.0.0. I can't reproduce it with 1.9.4 using yarn init -y && yarn add babel-cli@6.24.1 stylelint@7.9.0 webpack@3.1 && yarn check

[cprussin]

@arcanis Just wanted to ping you on this, this appears to have been fixed and then regressed, do you have any suggestions for a workaround that we can use in the meantime?

[betaorbust]

This is currently throwing a pretty big wrench in my team's development workflow.
Any updates @arcanis?
Thanks!

[arcanis]

Hey! Yes and no. Tldr: don't use yarn check (it doesn't put your project at risk).

Despite its name, yarn check is a buggy command that probably shouldn't be used (yarn install doesn't need yarn check to work, and yarn check requires us to maintain a separate logic that we don't have the resources to keep up-to-date). Don't use it. Ideally it should be moved into a separate and generic package that could be used whatever is the package manager you use.

I've juste submitted an RFC to remove it in the next major bump, actually: yarnpkg/rfcs#106

[nkovacs]

I used yarn check in CI to ensure that the lockfile is up to date, to catch things like forgetting to commit the lock file changes or using npm, which would not update yarn.lock.
I guess I'll use yarn install --frozen-lockfile instead in CI.

[clinyong]

@arcanis Can we update the doc? It's so confused...