poetry: "poetry install" when everything is already installed is very slow

• [X ] I am on the latest Poetry version.

• [X ] I have searched the issues of this repo and believe that this is not a duplicate.

• OS version and name: macOS Mojave 10.14.3

• Poetry version: 0.12.11

Issue

Did this:

poetry new foo
cd foo
poetry install

so far it’s fine, but if I do poetry install, it says there is nothing to do but it still takes 7 seconds. I was looking into poetry because I was frustrated with pip being slow when it did nothing, but it seem poetry is even slower 😦