Add convenience API for copying system MIME DB to test directories
As per this comment on !505 (merged), it would probably be a good idea if we:
- Dropped, or reduced suggestions to use
g_content_type_{get,set}_mime_dirs()
- Added some
g_test_*
API to copy the system MIME DB into the directories created byG_TEST_OPTION_ISOLATE_DIRS
That way, tests which depend on shared-mime-info can continue to work, but without pointing at system data and potentially modifying it, and without having to expose the concept of the system MIME database in the GContentType
API (as g_content_type_{get,set}_mime_dirs()
, since it’s specific to the XDG MIME handling and not cross-platform.
This needs to be done before 2.60 if we want to remove the g_content_type_{get,set}_mime_dirs()
APIs, since 2.60.0 would be their first stable release.