Failure on empty CPM_SOURCE_CACHE about cpm.cmake

[TheLartians]

What would be the expected behaviour in that case? Note that if you want to clear an environmental variable you can use the unset command.

unset CPM_SOURCE_CACHE

[jhasse]

Maybe a warning/error message like "CPM_SOURCE_CACHE is empty" or something like that?

[Andres6936]

In my opinion, this must be a precondition [CPM_SOURCE_CACHE ! = Null or Empty] that must be satisfied, this avoids adding code to handle this situation and keeps the [CPM] script simple.

[TheLartians]

I agree, I was wondering if there are any situations where one would want to set the Cache dir to an empty path, though probably not. So the solution would be "empty string" = "not set".

[flagarde]

@TheLartians Even if it's not very good, user could expect/wanr to have the cache in source directory or binary