F1 (real, small-window misbehavior). `dired.revert`'s re-seat runs after
the read settles, and `pmacs.editor.move_to_line` is AMBIENT -- it moves
whatever window is active. A user who switched buffers (or hit `q`)
while the re-read was in flight had an unrelated buffer's cursor moved
to a line index that only means something in the dired listing. The
paint was already safe because it names its buffer; the seat now runs
only while dired is still the active buffer, and `seat_cursor`'s doc
says which callers are unconditionally in the right place and why.
Pinned by a test that starts the revert, switches to a six-line file
before the pump, and asserts that buffer's cursor never moved -- and
that the dired buffer still reverts when it IS active.
F2 (a trap set for Stage 3). `fmt_size` used `%10d`, so a size past ten
digits -- 10 GB and up, ordinary for VM images and core dumps -- widened
the field and shifted mtime and name right on that line alone. Cosmetic
today, but `_layout` is exported as a contract and Stage 3's
column-classifying intercept is planned against it. It now takes
`fmt_mtime`'s discipline: exact bytes while they fit, else a
fixed-width magnitude, so precision yields to the invariant rather than
the other way round. This is not the deferred human-readable column --
the exact count still shows right up to where it cannot. Pinned with a
sparse 12 GB fixture that skips if the filesystem refuses it.
F3 (honesty and a doubled read). The symlink arm claimed the probe cost
"one syscall"; it was a full `read_dir` -- opendir plus one lstat per
child -- and on success `open_directory` immediately read the same
directory again. Since `open_directory` reads before touching editor
state and raises having changed nothing (acceptance 15's invariant), its
failure IS the "not a directory" answer: the probe is gone, one read
remains, and the comment says what it actually does. New test pins both
arms -- a symlink to a directory descends under the path the user walked
(canonicalization is lexical, so the link is not resolved), and a
symlink to a file opens with the target's contents.
F4 (deliberate failure mode). A tolerant listing recorded readdir
iterator errors without bound, and `std::fs::ReadDir` need not terminate
after yielding one. Cancellation is NOT an adequate backstop here --
which is the reason for a constant rather than a comment saying it is: a
dired listing carries no supersede key, so nothing cancels it. A
directory whose iterator produces nothing but errors now fails with the
last error the way an unopenable directory does, after
READDIR_MAX_CONSECUTIVE_ENTRY_ERRORS; the counter resets on any entry
that materializes. Documented as untested and why: faking a failing
iterator needs the walk generic over it, a refactor with no other
consumer.
Smaller notes, all taken: READ_ONLY_LIMIT renamed NAME_VARIANT_LIMIT (it
caps `<2>`..`<99>`, nothing read-only); `fmt_perms`' omission of
setuid/setgid/sticky documented as a decision tied to the M8.3 fixture's
nine-bit parser; `format_outcome` binds the slice in the pattern instead
of re-traversing; and `pmacs.path.canonicalize`'s `to_string_lossy` is
noted as inside the existing non-UTF-8-path deferral rather than an
exception to it.
Process note, learned the hard way twice now: the round-1 dired.lua
fixes were briefly wiped because a mutation-bite helper restores with
`git checkout --`, which reverts to HEAD -- so a fix must be committed
BEFORE it is bitten, not after.
Levi Neuwirth
531fdf404e