These options can be set with options().
Details
sparsevctrs.verbose_materialize
This option is meant to be used as a diagnostic tool. Materialization of sparse vectors are done silently by default. This can make it hard to determine if your code is doing what you want.
Setting sparsevctrs.verbose_materialize is a way to alert when
materialization occurs. Note that only the first materialization is counted
for the options below, as the materialized vector is cached.
Setting sparsevctrs.verbose_materialize = 1 or
sparsevctrs.verbose_materialize = TRUE will result in a message being
emitted each time a sparse vector is materialized.
Setting sparsevctrs.verbose_materialize = 2 will result in a warning being
thrown each time a sparse vector is materialized.
Setting sparsevctrs.verbose_materialize = 3 will result in an error being
thrown each time a sparse vector is materialized.