While I'm unsure about why `cmPackageInfoArguments` was originally
written the way it was, in its current form, the way command sub-parsers
work, the parser never considers arguments associated with a sub-parser
if the sub-parser keyword isn't present. This means that the arguments
associated with `cmPackageInfoArguments` are treated as unknown, and the
logic to reject them being set if `PACKAGE_INFO` is not present can
never actually execute. Therefore, remove it, and remove the associated
(and effectively useless) `enable` argument to its `Check` method.
Instead, ensure that the package name is actually specified. The only
case in which the parser will create the `optional` associated with the
sub-parser arguments is if the relevant keyword (i.e. `PACKAGE_INFO`) is
present. However, while the associated value is `NonEmpty`, the way we
are using the parser does not actually enforce this, and it looks like a
correct fix may be a breaking change. Therefore, enforce it manually for
now.
Add `LICENSE` and `DEFAULT_LICENSE` arguments to the `PACKAGE_INFO`
modes of the `install` and `export` commands. If not otherwise
specified, the `LICENSE` will be taken from the project's
`SPDX_LICENSE`, if available.
Add support for specifying CPS's supplemental `description` and
`website` attributes. Add ability to inherit these from the `project()`,
similar to how version information can be inherited.
Modify {export,install}(PACKAGE_INFO) commands to inherit version
information from the current project in situations where it seems
reasonable to do so. Add an option to explicitly request inheritance
from a specific project.
This leverages the recently added project(COMPAT_VERSION).
CPS package metadata involves a fair amount of passing around a
particular set of values, as well as shared argument handling, which is
only going to increase as additional features are added. In order to
reduce code duplication (now and going forward), create a helper class
to handle the shared argument parsing and to serve as a container to
pass metadata values.
Matthew Woehlke