If we fail as a result of `set -x`, It's often not completely obvious
which command failed or how. Use a trap on ERR to show the command that
failed, and its exit status.
Signed-off-by: Simon McVittie <smcv@collabora.com>
[Originally from bubblewrap commits c5c999a7 "tests: test --userns"
and 3e5fe1bf "tests: Better error message if assert_files_equal fails";
separated into this commit by Simon McVittie.]
Follow the precedent set in https://github.com/coreos/rpm-ostree/pull/2106
and rename the directory, to more clearly move away from the
"uninstalled" test model. Prep for Rust-based tests.
Simon McVittie
Alexander Larsson
Matthew Leeds
Colin Walters