Created attachment 328007 [details]
./test-uri file:///path/to/file.pdf

Backstory here:
http://entrenchant.blogspot.com/2016/03/xdg-open-arcanery.html
https://bugzilla.redhat.com/show_bug.cgi?id=1329804
https://phab.enlightenment.org/T3555

At a minimum, evince-previewer should be fixed to not choke on a URI argv[0].
The problem is here (line 197) in previewer/ev-previewer.c:

      if (!g_file_test (argv[1], G_FILE_TEST_IS_REGULAR)) {
               g_printerr ("Filename \"%s\" does not exist or is not a regular file\n", argv[1]);
              return 1;
      }

g_file_test returns failure when being passed a raw URI. I've attached simple test code which illustrates this fact. 

I tried quite a few different things to fix this, but none of them worked. :/