--include-env forces the inclusion of environment variables regardless
of the use of data file input. Environment variables take precedence over
values from data files.
Coverage decreased (-0.6%) to 57.895% when pulling 0e05d5487c6813501c5cbd2f69cbf376be2d1bba on include-env into 17f93bd3ef10e8c9712a8f81f59455f5203cfff3 on master.
--include-env forces the inclusion of environment variables regardless of the use of data file input. Environment variables take precedence over values from data files.
Closes #28