stow 2.3.0 added external runtime dependencies on Hash::Merge and
Clone::Choose. Historically stow hasn't had runtime dependencies other
than Perl itself, which is a useful property if you're managing the
installation of Perl using stow; the bootstrapping instructions in
stow's manual would need updating to describe how to install these two
modules (and any dependencies they have now or in the future) as well.
However, Hash::Merge is much more general than stow actually needs, so
replace the merge() call with a few lines of equivalent code -- this
avoids the external dependencies, and is clearer than the merge()
call.
Many thanks to Adam Sampson for this patch:
https://lists.gnu.org/archive/html/bug-stow/2019-06/msg00001.html
Why:
* We want to selectively apply expansion to:
* Only options from stowrc files.
* Only options that take a path.
* This requires ability to:
* Differentiate cli options from stowrc options
* Distinguish between individual stowrc options.
This change addresses the need by:
* Options from ARGV and stowrc files are separately parsed, resulting in
two options hashes.
* Creating an option hash from stowrc files allows modification of
specific arguments without having to rely on something like regex
parsing of the options.
* get_config_file_options modified to return options hash.
* Uses the same parse_options function that parses ARGV
* Add Hash:Merge to dependencies in order to merge the two option
hashes.
* process_options() merges the two option hashes.
* Get option hash for ARGV
* Get option hash from get_config_file_options().
* Merge the two hashes with Hash::Merge.
* Sanitation and checks are ran on the merged options.
* The options -S, -D, and -R are ignored in stowrc files.
* Due to the way argument parsing happens, the effect of these
actions is not carried from stowrc into parsing of cli options.
* It doesn't seem to make sense to put these options in stowrc
anyway.
