Login doesn't work if user registration is disabled

[Oneiros90]

I'm using verdaccio as NPM server, with user registration disabled.
I configured verdaccio's htpasswd file as my "whitelist" file.

Then if I try to login to verdaccio using this command:
npm-cli-login -u username -p password -e test@test.com -r http://localhost:4873

verdaccio's response is

http --- 127.0.0.1 requested 'PUT /-/user/org.couchdb.user:test.username/-rev/undefined'
error--- authenticating for user test.username failed. Error: bad username/password, access denied
http --- 200, user: null(127.0.0.1), req: 'PUT /-/user/org.couchdb.user:test.username/-rev/undefined', bytes: 226/0
error--- the user test.username could not being added. Error: user registration disabled

In other words, it looks like npm-cli-login tries to register a new user, but I just want to authenticate!
Using npm login --registry http://localhost:4873 it works without problems. But I can't use that, since it needs cli interaction

[LordOfTheDings]

Same issue here.