Re: [PATCH 3/3] Enable parallel tests

René Scharfe [off-list ref] writes:

test="trash directory/$this_test"?

The advantage would be that all trash was still inside "trash
directory".  Not sure if the extra directory level would break
something.  (Note: $this_test is defined a bit later in the script.)

The extra directory level may break some tests that refer to their
precomputed test vectors in ../tXXXX, but I think they should be fixed
regardless.  That's what $TEST_DIRECTORY is for.

I'd very much prefer having 't/trash directory/t1234-test-name/' so that
we can say "make clean" to clean "t/trash directory" in one go.