Note that this release makes the new install format (and thus new installer or an alternative supported install method) a hard requirement.
If you are currently installing using the deprecated get-poetry.py, you will be unable to install Poetry 1.2.
Additionally, Poetry 1.1 installed using get-poetry.py will be not be able to update using poetry self update.
See the 1.2.0 release announcement for a summary of how to migrate to install.python-poetry.org if you fall into one of these two cases.