how to properly us a *file* dependency that isn't a zip file inside of a port?

[Cazadorro]

I have a non extractable file that needs to be used as a port's dependency, that I would normally get through fetchcontent. My problem is that unless I use one of VCPKG's blessed functions, it looks like I can't easily have a "${SOURCE_PATH}" to use for my files location. I have a CMakeLists.txt and a /cmake directory I intended to copy into a valid ${SOURCE_PATH}, which I hoped would enable me to have VCPKG pretend it was a regular cmake project download.

I was looking at vcpkg_download_distfile but it appears to pretty much always be paired with a "extract_source_archive" or something which retrieves the source location, so I'm not sure how to manage that myself.

How do I handle a single file dependency (not a whole repo, or cmake project) that I need to download, and properly use a ${SOURCE_PATH} for my port?

[dg0yt]

(With the background of #36037, but in more general words:)

SOURCE_PATH is just a variable pointing to the project source. If the build rules must be maintained in the port, the variable can be set to a subdir of the port dir.

• Offer CMakeList.txt and any immutable auxiliary files, e.g. C sources, in this SOURCE_PATH dir.
• Pass the download location of the desired single file as a CMake option.
• If some level of isolation is desired , let your cmake project copy the downloaded file into the binary dir, and use that dir to access the file.