Keeping the VM state test across several run sometimes lead to subtle
and hard to spot errors in practice. We delete the VM state which
contains (among other things) the qcow volume.
We also introduce a -K (--keep-vm-state) flag making VM state to
persist after the test run. This flag makes test-driver.py to match
its previous behaviour.
Turns out, on smaller images (~800MiB uncompressed sdcard image size),
the current fudge factor is way too small to even get the system to the
phase where it can resize itself.
I first tried with 1.05, but it wasn't enough.
xchg is advertised as a bidirectional exchange dir, but file content
transfer from host to VM fails due to caching:
If a file is read in the VM and then modified on the host, subsequent
re-reads in the VM can yield old, cached data.
This is caused by the use of 9p's cache=loose mode that is explicitly
meant for read-only mounts.
9p doesn't provide any suitable cache modes, so fix this by disabling
caching.
Also, remove a now unnecessary sync in the test driver.
These syncs have the goal to transfer host filesystem changes to the VM,
but they have no effect because 1) syncing in the VM can't possibly pull
in host data and 2) 9p is accessing the host filesystem on the cached
layer anyways, so even syncing on the host would have no effect in the
VM.
The test harness provides the commands it wishes to run in Bourne
syntax. This fails if the user uses a different shell. For example,
with fish:
machine.wait_for_unit("graphical-session.target", "alice")
machine # fish: Unsupported use of '='. To run '-u`' with a modified environment, please use 'env XDG_RUNTIME_DIR=/run/user/`id -u`…'
machine # XDG_RUNTIME_DIR=/run/user/`id -u` systemctl --user --no-pager show "graphical-session.target"
machine # ^
machine # [ 16.329957] su[1077]: pam_unix(su:session): session closed for user alice
error: retrieving systemctl info for unit "graphical-session.target" under user "alice" failed with exit code 127
This completes the removal of the nested log feature, which previously
got removed from Nix, Hydra, stdenv and GNU Make. In particular, this
means that the output of VM builds no longer contains a copy of
jQuery.
If a program (e.g. nixos-install) writes more than 1000 lines to
stderr during execute(), then process_serial_output() deadlocks
waiting for the queue to be processed. So use an unbounded queue
instead.
We should probably get rid of the structured log output (log.xml),
since then we don't need the log queue anymore.
This avoids a possible surprise if the user is using `nixpkgs.system`
and `nesting.children`. `nesting.children` is expected to ignore all
parent configuration so we shouldn't propagate the user-facing option
`nixpkgs.system`. To avoid doing so, we introduce a new internal
option for holding the value passed to eval-config.nix, and use that
when recursing for nesting.
Most VM tests have been migrated to use the python test driver
(introduced in #71684), the migration is tracked in #72828 (which also
thankfully uncovered and fixed many currently broken tests)
While increasing the acceptance and adoption of NixOS integration tests
by using a more popular language, there was also nobody willing to do
larger refactors in the currently very convoluted test infrastructure.
We plan to remove the perl infrastructure between the 20.03 and 20.09
release, to be able to do these refactorings.
Some people might be using Perl tests in their internal CI, so print a
warning for 20.03, and give users time to move to the python testing
infrastructure.
