Isn't the role of theforce flag to ignore warnings ?

Yes, but the way this is being done makes no sense. It's failing immediately on warnings. Warnings in jsdoc and warnings in grunt are two different things. Most importantly, even if you --force, you don't see all the warnings and errors. jsdoc doesn't even die during errors, it keeps going and shows you all of them. I mostly just want all of the output, warnings included.

This feature would be really useful for me too. I'm writing ES6 modules and because I have to useforce I'm missing genuine jsdoc errors because the exit status is always 0. Being able to ignore warnings (because they are almost always about ES6 import/export nodes) but still fail on errors would be very helpful at least until all ES6 syntax is fully supported.

I'll merge it as soon as I have some time to do it.

Merged but I need to handle theignoreWarning option and do some testing before publishing to npm.