Arrow R doesn't build correctly if Arrow C++ was configured with lowercase flags

[asfimport]

I use to configure ARROW C++ using lowercase flag names "on" instead of {}"ON"{}, that works fine with the C++ library and Python library, but leads to build errors on R.

That's because the R build process looks for compile flags in ArrowOptions.cmake and those compile flags are compared with the uppercase ones.

So in my ArrowOptions.cmake I had

### Build the Parquet libraries
set(ARROW_PARQUET "on") 

while the R build script was looking for

grep 'set(ARROW_PARQUET "ON")' $ARROW_OPTS_CMAKE 

this can be addressed by making those greps case insensitive

Reporter: Alessandro Molina / @amol-
Assignee: Alessandro Molina / @amol-

PRs and other links:

• GitHub Pull Request #12017

_{Note: This issue was originally created as ARROW-15185. Please see the migration documentation for further details.}

[asfimport]

Jonathan Keane / @jonkeane:
Issue resolved by pull request 12017
#12017