I'm running yarn install. Part of the output is as follows:
yarn install v1.10.1
info No lockfile found.
[1/4] Resolving packages...
warning @beaker/webdb > level-browserify > level-js > xtend > object-keys@0.4.0:
The question: What does this warning mean?
More info
The whole output:
yarn install v1.10.1
info No lockfile found.
[1/4] Resolving packages...
warning @beaker/webdb > level-browserify > level-js > xtend > object-keys@0.4.0:
warning karma > log4js > circular-json@0.5.9: CircularJSON is in maintenance only, flatted is its successor.
[2/4] Fetching packages...
info fsevents@1.2.4: The platform "linux" is incompatible with this module.
info "fsevents@1.2.4" is an optional dependency and failed compatibility check. Excluding it from installation.
[3/4] Linking dependencies...
warning "angular4-material-table > @angular/forms@6.1.10" has incorrect peer dependency "@angular/platform-browser@6.1.10".
[4/4] Building fresh packages...
success Saved lockfile.
Done in 202.88s
What's happening here is that object-keys@0.4.0 has been marked as deprecated, but there is no message.
You can see via
npm view object-keys@0.4.0 --json
that there is a deprecated field with an empty string. I'm not sure how npm clients are supposed to treat this but yarn simply checks if deprecated is a string and displays a warning with the provided deprecation message.
Unfortunately, the warning doesn't say anything about it being about a deprecation and coupled with an empty message, you end up with a mystery warning.