A 27-assertion suite for dwm_config.sh, the highest-scored remaining
allowlisted lib. It drives the lib for real inside the jail: rewriting dwm.c
with perl, appending to config.h, compiling with cc and installing into
/usr/local/bin. The generated content is asserted, not just the call.
LATENT BUG, found by writing the test: apply_fullscreen_confine_hook does
`on=$(grep -c 'pconfine-auto on' "$src")`, and grep -c exits 1 when the count
is zero. The caller runs `set -euo pipefail`, so the function aborted at that
line exactly when the count was zero -- which is precisely when the
"setfullscreen/unmanage were likely refactored upstream" warning three lines
below was the thing needed. The warn branch was dead code in the only
situation it exists for. Both call sites now use `|| true`, and the suite
asserts the warning fires.
Measured: dwm_config.sh 35/73 = 47.95%. It STAYS on the allowlist -- the bar
is 100% and it is measured, not asserted.
That number is an under-report. An `exit 43` sentinel proves build_install,
build_pointer_confine, write_session_files and verify all execute inside the
jail while kcov reports their bodies at zero hits. One kcov artifact is now
CONFIRMED against a minimal repro: continuation lines inside a multi-line
quoted argument (the `perl -0777 -pe '...'` blocks) are counted as
statements that never run, which is the wrong denominator. A sixth
hypothesis -- that the exec-ing sudo shim or a pipeline loses the trace --
was tested and disproven. The two-strike time-box on this hunt is spent;
docs/shell-split-verification.md records what is known, including the
exit-sentinel technique for telling a tracing failure from an aborted suite.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016sxxsDHWgdRhmdmzNMA6XM
ci_mirror.sh and shell-tests.yml discovered every */lib/tests/run_all.sh and
invoked it bare. The features/lib suite refuses to run bare -- that guard is
what stops it rewriting the real /etc -- so the pre-push gate blocked all six
pending commits, and CI would have gone red on the same suite the moment they
landed.
A suite now DECLARES its jail requirement with a jail_args file beside its
run_all.sh, holding the --bind/--seed-* flags it needs. Both consumers branch
on the marker. The 105 still-allowlisted libs were scored on root ops and
system writes, so most future suites will need the jail too; naming the path
in two runners would drift, which is the failure ci_mirror.sh's own comments
say it exists to prevent.
Both branches fail closed: a marker present but empty is an error, not a skip.
Verified the extracted flags reproduce the independently measured
dot_resolver_install.sh 39/39 = 100.00%, and that the other five suites still
pass bare.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016sxxsDHWgdRhmdmzNMA6XM
rpi_nc_install.sh is one 200-line function that apt-installs 24
packages, seeds MariaDB, rm -rf's /var/www/nextcloud, rewrites Apache
and PHP config and installs a www-data crontab. 29 assertions, run for
real inside the jail. The destructive step is the point: a bug in
`rm -rf /var/www/nextcloud` is invisible to any check that does not
actually run it.
Two latent bugs in the ALREADY-COMMITTED nc_php suite, both found by
finally reading its assertion results instead of only its coverage
percentage. It was failing 2 of 29 in isolation:
- the cron entry arrives on crontab's STDIN, not in argv, so asserting
on the call log could never have passed for the right reason. The
stub now records stdin.
- configure_mariadb's stdout is eaten by `db_password=$(...)`, so the
phase-order marker now goes to stderr and the capture reads both.
Suites now: 28 + 30 + 29 = 87 assertions, 0 failures.
KNOWN AND UNEXPLAINED: kcov mis-measures rpi_nc_install.sh at 10/88 =
11.36%, recording lines 13-54 and nothing after -- yet the code past
line 54 provably runs, since /root/.nextcloud_db_password and
/etc/apache2/sites-available/nextcloud.conf both exist afterwards. The
three obvious culprits were each tested against a minimal reproduction
and DISPROVEN: kcov traces fine past a heredoc, into a $( ) command
substitution, and past a heredoc-fed stub reading stdin via $(cat).
The file stays on the allowlist and the suite is kept for its
assertions, not its percentage. Do not 'fix' the number by weakening a
test.
dot_resolver_install.sh 39/39 = 100.00%; nc_php.sh 84/85 = 98.82%.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DbD4nco3EgL1UFoZKmKsLE
nc_php.sh was the next-hardest library on the allowlist. It targets a
Debian Raspberry Pi -- it edits /etc/php/<ver>/apache2/php.ini, drives
occ as www-data and installs a crontab -- so none of its write targets
exist on this Arch host and the jail had nothing to mirror.
- --seed-dir / --seed-file create the paths a foreign-platform subject
expects. Verified with a probe: /etc/php/8.2/apache2 exists inside
the jail while /etc/php does not exist outside it.
- A failed bind is now FATAL, and missing mountpoints are created
first. A bind that fails silently is indistinguishable from
unreachable code in the report, which is the misdiagnosis this
runner exists to prevent.
- Mirroring skips unreadable targets (/root as a normal user) rather
than aborting under set -e.
nc_php.sh: 84/85 = 98.82%, 24 assertions. It STAYS on the allowlist,
because 98.82% is below the bar. Line 111 -- the crontab first-run
fallback -- hung the suite on both attempts to cover it, so it is left
uncovered and documented rather than tried a third time.
Two harness hazards found the hard way and written down: a top-level
stub function shadows the subject's own function for every later
assertion (this silently dropped coverage 83.53% -> 57.65% while the
tests still passed), and a stub for a piped-into command must drain
stdin or the writer takes SIGPIPE.
dot_resolver_install.sh still measures 39/39 = 100.00%.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DbD4nco3EgL1UFoZKmKsLE
The gate was a presence check -- 'a run_all.sh exists beside this lib' --
which an empty suite that asserts nothing satisfies. It now measures.
100% is reachable with no suppressions and no production source changes:
run the suite inside a user+mount namespace and the sudo-writes, systemd
units and nftables rules execute for real against a throwaway /etc.
- meta/scripts/shell_coverage_jail.sh: the runner, promoted out of a
session scratchpad. Two fixes it needed on the way: bind targets mirror
the real directory tree (an empty bind makes writes fail with ENOENT,
which reads as unreachable code), and sudo gets a pass-through stub
because real sudo cannot setresuid inside a userns.
- It fingerprints git status before and after and fails the run if a
write escapes the jail. Verified with a deliberate escapee.
- dot_resolver_install.sh: 39/39 = 100.00%, 28 assertions. Picked by
scoring every allowlisted lib on root ops, system writes and
destructive calls -- it scored highest in the repo. Allowlist 106 -> 105.
- jscpd was already over its own threshold at 2.45% and would have
rejected every commit staging a .sh file. Excluding vendored .venv/
shell alone gives 1.67%; also excluding lib/tests/ gives 1.47%.
The gate is deliberately NOT wired into the hook chain yet.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DbD4nco3EgL1UFoZKmKsLE
