FreeBSD rpi4 13.0-CURRENT FreeBSD 13.0-CURRENT #0 r368820: Sun Dec 20 23:25:08 UTC 2020 root@rpi4:/usr/obj/usr/src/arm64.aarch64/sys/GENERIC arm64
..., with DOCS enabled, ...
# This file is auto-generated by 'make config'.
# Options for py37-reportlab-3.5.55
_FILE_COMPLETE_OPTIONS_LIST=CJK DOCS FREETYPE
..., when I last attempted to upgrade via ports, updating from py37-reportlab-3.5.55 to py37-reportlab-3.5.57 failed since userguide.pdf was not created. A manual ...
mkdir -p /usr/local/lib/python3.7/site-packages/docs/userguide ; ( cd /usr/ports/print/py-reportlab/work-py37/reportlab-3.5.57/docs/userguide/ && python3.7 genuserguide.py )
... sufficed for the subsequent ...
make all deinstall-all reinstall package clean
... to succeed.
I am not sure about the exact reason. I checked my build logs and found that it's built properly. For your reference you can check the logs.
However I am updating py-reportlab to 3.5.60 within couple of hours.